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Title: Comparative anatomy and systematics of twelve woody Australasian genera of the Saxifragaceae /
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Title: Comparative anatomy and systematics of twelve woody Australasian genera of the Saxifragaceae /
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Language: English
Creator: Hils, Matthew Henry, 1955-
Copyright Date: 1985
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Table of Contents
    Title Page
        Page i
    Acknowledgement
        Page ii
    Table of Contents
        Page iii
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        Page v
        Page vi
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        Page viii
        Page ix
        Page x
        Page xi
        Page xii
        Page xiii
        Page xiv
    Abstract
        Page xv
        Page xvi
    Main
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Full Text














COMPARATIVE ANATOMY AND SYSTEMATICS OF
TWELVE WOODY AUSTRALASIAN GENERA
OF THE SAXIFRAGACEAE








By

MATTHEW HENRY HILS


A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN
PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR THE DEGREE OF DOCTOR OF PHILOSOPHY



UNIVERSITY OF FLORIDA


1985













ACKNOWLEDGEMENTS

I thank the members of my committee, Drs. Lucansky,

Ferl, Huffman, Judd and Stern for their guidance and pa-

tience in helping me complete this dissertation. I am

especially grateful to Dr. Lucansky for his extensive help

in organizing and criticizing this dissertation, and Dr.

Stern for posing the research problem and providing the

samples and materials with which to work. Special thanks go

to Dr. Nordlie for his eleventh hour efforts. My thanks

also go to the rest of the faculty and graduate students of

the Department of Botany for the many questions they an-

swered and their encouragement. I express gratitude to my

colleagues, friends and students at Hiram College who have

been very supportive during the past year. Robert Sawyer

and Robert Kiger provided help with translation of a Latin

description, and Wes Tree assisted with the photographs. I

am very grateful to John W. Thieret, friend and colleague,

for his counsel and assistance over the past six years. I

also am very fortunate to have the full support of my family

in my work; I owe them more than I could ever repay. Last-

ly, I dedicate this work to my wife, Wendy E. Mahon-Hils,

who has provided the illustrations within, but more impor-

tantly, has given me more love and understanding than I

could ever hope for in married life. Without her, this work

could not have been completed.

















TABLE OF CONTENTS


SECTION


PAGE


ACKNOWLEDGEMENTS... .....................................ii

LIST OF TABLES...........................................v

LIST OF FIGURES.........................................vi

KEY TO TISSUES: NODES AND PETIOLES....................xiv

ABSTRACT.... ............................................xv

INTRODUCTION... ..........................................1


Systematics of the Saxifragaceae.......
Anatomical Work on the Saxifragaceae...
Anatomical Work on New Zealand Genera..
Anatomical Work on the Cunoniaceae.....
Rationale for the Present Study.........


.............1
........... 3
.............6
.............9
............10


MATERIALS AND METHODS....................................14

RESULTS .................................................19


Tetracarpaea Hook. ....................
Ixerba A. Cunn. .......................
Bauera Banks ..........................
Anopterus Labill. .....................
Cuttsia F. v. Muell. ..................
Abrophyllum Hook. f .................
Carpodetus J. R. & G. Forst. ..........
Corokia A. Cunn ......................
Argophyllum J. R. & G. Forst. .........
Donatia J. R. & G. Forst ............
Anodopetalum A. Cunn. .................
Aphanopetalum Endl. ..................


............19
............31
............43
............59
............73
............85
............95
........... 110
.......... 127
........... 141
........... 150
.......... 160


DISCUSSION ........................................... 168

Anatomy of Twelve Australasian Genera.............168
Relationships of Ixerba ...........................173
Relationships of Anopterus........................176
Relationships of Cuttsia and Abrophyllumn..........179
Relationships of Carpodetus .......................181
Relationships of Corokia and Argophyllum...........185
Relationships Among the Escallonioideae...........190


iii







Possible Delimitation of the Escallonioideae......193
Relationships of Tetracarpaea.....................195
Relationships of Bauera ...........................198
Relationships of Anodopetalum.....................202
Relationships of Aphanopetalum....................204
Relationships of Donatia...........................206
Australasian Genera and Geological History........ 209

CONCLUSIONS.......................................................... 211

SUMMARY............ ..................................... 220

APPENDIX...............................................221

LITERATURE CITED......................................... 229

BIOGRAPHICAL SKETCH.................................... 240















LIST OF TABLES


TABLE PAGE

Table 1. Twelve Australasian genera classified according
to Adolph Engler...........................................13

Table 2. Woody saxifragaceous species from Australasia
examined anatomically.......................................... 18

Table 3. Anatomical features of eleven Australasian
woody saxifragaceous genera ..............................169

Table 4. Specimens of Australasian woody Saxifragaceae
examined anatomically............................... .....222















LIST OF FIGURES

FIGURE PAGE

Figure 1. Leaf of Tetracarpaea tasmannica...............26

Figure 2. Vein ending of T. tasmannica..................26

Figure 3. Transverse sections of a node and petiole
of T. tasmannica........................................... 26

Figure 4. Transverse section of a leaf of T.
tasmannica................................................. 28

Figure 5. Transverse section of the abaxial epidermis
of a leaf of T. tasmannica ................................28

Figure 6. Transverse section of a leaf of T.
tasmannica................................................. 28

Figure 7. Marginal tooth of a leaf of T. tasmannica.....28

Figure 8. Transverse section of the secondary xylem of
T. tasmannica.............................................. 30

Figure 9. Radial section of the secondary xylem of T.
tasmannica................................................. 30

Figure 10. Secondary xylem of T. tasmannica.............30

Figure 11. Tangential section of the secondary xylem of
T. tasmannica.............................................. 30

Figure 12. Radial section of the secondary xylem of T.
tasmannica................................................. 30

Figure 13. Leaf of Ixerba brexioides....................38

Figure 14. Vein ending of I. brexioides.................38

Figure 15. Transverse sections of a node and petiole
of I. brexioides.......................................... 38

Figure 16. Transverse section of a leaf of I.
brexioides................................................. 40

Figure 17. Optically anisotropic crystalloid from a leaf
of I. brexioides........................................... 40








Figure 18. Transverse section of the midvein of a leaf
of I. brexioides......................................... 40

Figure 19. Paradermal section of the abaxial epidermis
of a leaf of I. brexioides................................40

Figure 20. Transverse section of the abaxial epidermis
of a leaf of I. brexioides................................40

Figure 21. Marginal creation of a leaf of I.
brexioides. .............................................. 42

Figure 22. Paradermal section of a marginal creation
of a leaf of I. brexioides................................42

Figure 23. Transverse section of the secondary xylem
of I. brexioides......................................... 42

Figure 24. Radial section of the secondary xylem of I.
brexioides............................................... 42

Figure 25. Tangential section of the secondary xylem
of I. brexioides......................................... 42

Figure 26. Radial section of the secondary xylem of I.
brexioides............................................... 42

Figure 27. Leaf of Bauera rubioides..................... 52

Figure 28. Diversity of leaf shapes in B. capitata......52

Figure 29. Vein ending of B. rubioides..................52

Figure 30. Diagrammatic representation of a node and
the nodal pattern of B. rubioides........................54

Figure 31. Transverse section of a leaf of B.
capitata..................................................56

Figure 32. Transverse section of a leaf of B. capitata
showing prismatic crystals near a vascular bundle........56

Figure 33. Transverse section of a leaf of B.
sessiliflora .............................................56

Figure 34. Transverse section of a leaf of B.
sessiliflora..............................................56

Figure 35. Paradermal section of the abaxial epidermis
of a leaf of B. rubioides................................56

Figure 36. Transverse section of the abaxial epidermis
of a leaf of B. capitata................................ 56


vii







Figure 37. Marginal serration of a leaf of B.
rubioides. ............................................... 56

Figure 38. Transverse section of a leaf of B.
capitata..................................................56

Figure 39. Transverse section of the secondary xylem of
B. rubioides ..................................... .........58

Figure 40. Radial section of the secondary xylem of B.
rubioides. ............................................... 58

Figure 41. Radial section of the secondary xylem of B.
sessiliflora..............................................58

Figure 42. Tangential section of the secondary xylem
of B. sessiliflora .......................................58

Figure 43. Leaf of Anopterus glandulosus................68

Figure 44. Vein ending of A. glandulosus................ 68

Figure 45. Transverse section of a node of A.
glandulosus.............................................. 68

Figure 46. Transverse sections of a petiole of A.
glandulosus.............................................. 68

Figure 47. Transverse sections of a petiole of A.
macleayanus ............................................. 68

Figure 48. Transverse section of a leaf of A.
glandulosus.............................................. 70

Figure 49. Transverse section of the midvein of a leaf
of A. glandulosus......................................... 70

Figure 50. Transverse section of the midvein of a leaf
of A. macleayanus.......................................... 70

Figure 51. Transverse section of the abaxial epidermis
of a leaf of A. glandulosus...............................70

Figure 52. Marginal creation of a leaf of A.
glandulosus.............................................. 70

Figure 53. Paradermal section of a marginal creation
of a leaf of A. glandulosus..............................70

Figure 54. Transverse section of the secondary xylem
of A. glandulosus........................................ 72

Figure 55. Radial section of the secondary xylem of
A. glandulosus........................................... 72


viii







Figure 56. Tangential section of the secondary xylem
of A. glandulosus........................................ 72

Figure 57. Radial section of the secondary xylem of A.
glandulosus. ............................................. 72

Figure 58. Leaf of Cuttsia viburnea.....................80

Figure 59. Vein ending of C. viburnea...................80

Figure 60. Transverse sections of a node and petiole
of C. viburnea........................................... 80

Figure 61. Transverse section of a leaf of C.
viburnea................................................. 82

Figure 62. Crystal sand in the spongy mesophyll layer
of a leaf of C. viburnea ................................. 82

Figure 63. Transverse section of the midvein of a leaf
of C. viburnea........................................... 82

Figure 64. Paradermal section of the abaxial epidermis
of a leaf of C. viburnea..................................82

Figure 65. Marginal serration of a leaf of C.
viburnea................................................. 82

Figure 66. Transverse section of the secondary xylem
of C. viburnea........................................... 84

Figure 67. Radial section of the secondary xylem of C.
viburnea........................................... ......84

Figure 68. Tangential section of the secondary xylem
of C. viburnea........................................... 84

Figure 69. Radial section of the secondary xylem of C.
viburnea.................................................84

Figure 70. Leaf of Abrophyllum ornans...................92

Figure 71. Vein ending of A. ornans.....................92

Figure 72. Transverse sections of a node and petiole
of A. ornans..............................................92

Figure 73. Transverse section of a leaf of A. ornans....94

Figure 74. Transverse section of a midvein of a leaf
of A. ornans.............................................94

Figure 75. Transverse section of the abaxial epidermis
of a leaf of A. ornans...................................94







Figure 76. Transverse section of the secondary xylem
of A. ornans .............................................94

Figure 77. Radial section of the secondary xylem of
A. ornans.................................................94

Figure 78. Tangential section of the secondary xylem
of A. ornans .............................................94

Figure 79. Leaf of Carpodetus serratus..................105

Figure 80. Domatium in the axil of a secondary vein
of C. serratus...........................................105

Figure 81. Vein ending of C. serratus..................105

Figure 82. Transverse sections of a node and petiole
of C. serratus...........................................105

Figure 83. Transverse section of a leaf of C.
serratus ................................................107

Figure 84. Transverse section of a leaf of C_
serratus ................................................107

Figure 85. Transverse section of a midvein of a leaf
of C. serratus...........................................107

Figure 86. Marginal serration of a leaf of C.
serratus ................................................107

Figure 87. Transverse section of the secondary xylem
of C. serratus...........................................109

Figure 88. Transverse section of the secondary xylem
of C. major..............................................109

Figure 89. Radial section of the secondary xylem of
of C. arboreus.......................................... 109

Figure 90. Tangential section of the secondary xylem
of C. serratus...........................................109

Figure 91. Leaf of Corokia macrocarpa..................120

Figure 92. Leaf of C. carpodetoides....................120

Figure 93. Vein ending of C. macrocarpa................120

Figure 94. Transverse sections of a node and petiole
of C. macrocarpa.......................................... 120

Figure 95. Transverse sections of a node and petiole
of C. virgata............................................122








Figure 96. Transverse section of a leaf of C.
carpodetoides............................................. 122

Figure 97. Transverse section of a midvein of a leaf
of C. virgata............................................122

Figure 98. Transverse section of a midvein of a leaf
of C. macrocarpa.......................................... 122

Figure 99. Transverse section of a leaf of C.
macrocarpa................................................ 124

Figure 100. Paradermal section of the abaxial
epidermis of a leaf of C. macrocarpa....................124

Figure 101. Transverse section of the abaxial
epidermis of a leaf of C. virgata.......................124

Figure 102. Multicellular, T-shaped trichome of C.
macrocarpa................................................ 124

Figure 103. Multicellular, T-shaped trichome of C.
virgata..................................................124

Figure 104. Multicellular, T-shaped trichome of C.
macrocarpa................................................ 124

Figure 105. Pitting between the terminal cell and the
uppermost stalk cell of a T-shaped trichome of
C. macrocarpa....................................... ..... 124

Figure 106. Transverse section of the secondary xylem
of C. buddleioides...................................... 126

Figure 107. Transverse section of the secondary xylem
of C. collenettei........................................126

Figure 108. Radial section of the secondary xylem
of C. collenettei........................................126

Figure 109. Tangential section of the secondary xylem
of C. whiteana.......................................... 126

Figure 110. Leaf of Argophyllum cryptophlebum..........136

Figure 111. Vein ending of A. nullumense...............136

Figure 112. Transverse sections of a node and petiole
of A. nullumense.......................................... 136

Figure 113. Transverse section of a leaf of A.
nullumense................................................ 138

Figure 114. Transverse section of the midvein of a
leaf of A. nullumense................................... 138








Figure 115. Transverse section of the abaxial
epidermis of a leaf of A. nullumense....................138

Figure 116. Pitting between the terminal cell and
uppermost stalk cell of a T-shaped trichome of
A. cryptophlebum.......................................... 138

Figure 117. Marginal serration of a leaf of A.
cryptophlebum............................................. 138

Figure 118. Transverse section of the secondary xylem
of A. nullumense........................................ 140

Figure 119. Radial section of the secondary xylem
of A. ellipticum........................................ 140

Figure 120. Tangential section of the secondary xylem
of A. ellipticum........................................ 140

Figure 121. Radial section of the secondary xylem
of A. ellipticum........................................ 140

Figure 122. Leaves of Donatia novae-zelandiae..........147

Figure 123. Portion of a lamina of D. novae-
zelandiae............................................... 147

Figure 124. Unilacunar, one-trace nodal pattern of
D. novae-zelandiae .......................................147

Figure 125. Transverse section of a leaf of D. novae-
zelandiae ............................... ............... 147

Figure 126. Portion of lamina of D. novae-zelandiae
proximal to the leaf apex............................... 147

Figure 127. Lignified parenchyma cells abaxial to
vascular bundles in leaves of D. novae-zelandiae........149

Figure 128. Paradermal section of a leaf of D. novae-
zelandiae...............................................149

Figure 129. Transverse section of the abaxial
epidermis of a leaf of D. novae-zelandiae............... 149

Figure 130. Multicellular, uniseriate trichome of D.
novae-zelandiae........................................... 149

Figure 131. Transverse section of a stem of D. novae-
zelandiae................... ............................ 149

Figure 132. Radial section of the secondary xylem of
D. novae-zelandiae ......................................149


xii







Figure 133. Leaf of Anodopetalum biglandulosum.........157

Figure 134. Vein ending of A. biglandulosum.............157

Figure 135. Transverse sections of a node and
petiole of A. biglandulosum .............................157

Figure 136. Transverse section of a leaf of A.
biglandulosum............................................. 159

Figure 137. Transverse section of a midvein of a leaf
of A. biglandulosum..................................... 159

Figure 138. Marginal creation of a leaf of A.
biglandulosum............................................. 159

Figure 139. Transverse section of the secondary xylem
of A. biglandulosum..................................... 159

Figure 140. Radial section of the secondary xylem
of A. biglandulosum..................................... 159

Figure 141. Tangential section of the secondary xylem
of A. biglandulosum..................................... 159

Figure 142. Leaf of Aphanopetalum resinosum............ 165

Figure 143. Transverse section of a stem and petiole
of A. resinosum......................................... 165

Figure 144. Transverse section of the avascular
stipules of A. resinosum.................................165

Figure 145. Vein ending of A. resinosum................165

Figure 146. Transverse sections of a node and petiole
of A. resinosum......................................... 167

Figure 147. Transverse section of a leaf of A.
resinosum................................................. 167

Figure 148. Transverse section of a midvein of a leaf
of A. resinosum......................................... 167

Figure 149. Marginal serration of a leaf of A.
resinosum................................................. 167


xiii












Key toTissues


and Petioles


Un


Sclerenchyma

Lignified
Parenchyma


Xylem


Collenchyma


Cork l Phloem


From Metcalfe and Chalk (1950) with minor modification


xiv


Nodes


Illllllllillll
II /II r I /I,















Abstract of Dissertation Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the
Requirements for the Degree of Doctor of Philosophy


COMPARATIVE ANATOMY AND SYSTEMATICS OF
TWELVE WOODY AUSTRALASIAN GENERA
OF THE SAXIFRAGACEAE

By

MATTHEW HENRY HILS

AUGUST 1985

Chairman: Terry W. Lucansky
Major Department: Botany

Vegetative anatomical data are provided for twelve

woody saxifragaceous genera from Australasia. These data

are used, where possible, to determine the taxonomic posi-

tion of these plants. The twelve genera are Tetracarpaea,

Ixerba, Bauera, Anopterus, Cuttsia, Abrophyllum, Carpodetus,

Argophyllum, Corokia, Donatia, Anodopetalum and Aphano-

petalum. Typically these taxa possess dorsiventral leaves

with uniseriate epidermides and anomocytic stomatal appara-

tuses. The nodal pattern is either unilacunar, one-trace or

trilacunar, three-trace. The wood possesses angular, soli-

tary pores, long vessel elements with oblique, scalariform

perforation plates, tracheids with spiral thickenings and

sparse axial parenchyma. Cuttsia, Abrophyllum, Carpodetus,

Ixerba, Anopterus, Corokia and Argophyllum possess most or

all of eleven anatomical features of an archetypical woody







saxifrage. While wood anatomy is similar among Tetracar-

paea, Bauera and an archetypical woody saxifrage, leaf anat-

omy is distinctive for each group. Donatia, Anodopetalum

and Aphanopetalum possess few anatomical features of an

archetypical woody saxifrage. Ixerba is anatomically iso-

lated from the Brexioideae, but is similar to Anopterus in

the Escallonioideae. Cuttsia and Abrophyllum are very simi-

lar anatomically and closely related. Anatomical data do

not support the maintenance of the tribe Argophylleae of the

Escallonioideae which includes Carpodetus, Corokia and Argo-

phyllum. Carpodetus is more similar anatomically to Cuttsia

and Abrophyllum than to Corokia and Argophyllum. Corokia

and Argophyllum are very similar anatomically and probably

closely related, but their taxonomic position remains

obscure. Anatomical data support the union of the genus

Argyrocalymma with Carpodetus, and the union of the genus

Colmeiroa with Corokia. Tetracarpaea and Bauera are anatom-

ically distinctive and isolated genera and may deserve fa-

milial status. Tetracarpaea is more closely allied to the

Saxifragaceae based upon its wood anatomy, while Bauera is

more closely allied to the Cunoniaceae because of its oppo-

site leaves and foliaceous stipules. The nodal, leaf and

wood anatomy of Anodopetalum is more similar to that of the

Cunoniaceae than to that of the Saxifragaceae. Aphano-

petalum and Donatia are readily distinguishable and isolated

from the Saxifragaceae, but their taxonomic positions remain

obscure. Donatia should probably be placed in its own

family, but Aphanopetalum remains an enigma.


xvi















INTRODUCTION


Systematics of the Saxifragaceae

Although the family Saxifragaceae, sensu lato, is cos-

mopolitan, most species occur in temperate regions. The

family contains trees, shrubs, vines, and herbs, and approx-

imately 40 genera contain woody species. The taxonomic

problems in the Saxifragaceae are numerous and well known

(e.g., Cronquist, 1968; Dahlgren, 1975; Stern, 1974b;

Takhtajan, 1980; Thorne, 1976, 1983), and occur at almost

every taxonomic level.

According to Engler (1928), the family consists of 15

subfamilies, 80 genera and approximately 1200 species.

Thorne (1976, 1983) and Schulze-Menz (1964) also recognize a

single large family that consists of 13-17 subfamilies and

78 to 80 genera. Other taxonomists have divided this group

of plants into either a few families (Cronquist, 1968, 1981;

Hutchinson, 1967) or many families (Airy Shaw in Willis,

1973; Dahlgren, 1975, 1980, 1983; Takhtajan 1966, 1980,

1983). These smaller families usually correspond to

Engler's (1928) subfamilies (Takhtajan, 1980), but may be

much more inclusive (Cronquist, 1981).

Despite these differing opinions concerning the number

of families, most taxonomists agree that the Saxifragaceae

belong to the order Rosales (Engler, 1928; Schulze-Menz,









1964; Cronquist, 1981; Thorne, 1983), or the roughly

equivalent order Saxifragales (Takhtajan, 1980). Dahlgren

(1975, 1980, 1983), however, deviated from this consensus

and split the various families into two superorders (Rosi-

florae and Corniflorae) distributed among three orders

(Cunoniales, Saxifragales, and Cornales). Hutchinson (1967)

divided Saxifragaceae along herbaceous and ligneous lines,

and placed the corresponding genera into his Saxifragales

and Cunoniales, respectively.

In addition to these largely unresolved taxonomic prob-

lems, the placement and delimitation of several genera is

questionable. Bauera, for example, has been placed in the

Saxifragaceae (Engler, 1928), the monogeneric Baueraceae

(Hutchinson, 1967), and the Cunoniaceae (Cronquist, 1981).

Aphanopetalum is another genus often placed in the Cunonia-

ceae, but its affinities are questionable (Dickison, 1980b).

Donatia is also enigmatic. Engler (1890) originally placed

this genus in the Saxifragaceae, but later (1928) was uncer-

tain of its affinities. Other taxonomists have placed

Donatia in the Stylidiaceae (Mildbraed, 1907; Thorne, 1976,

1983; Dahlgren, 1975, 1980, 1983) or in the monogeneric

Donatiaceae (Cronquist, 1981). Another bewildering genus,

Corokia, has been shuttled among the Saxifragaceae (Engler,

1928), Escalloniaceae (Takhtajan, 1980), Cornaceae

(Cronquist, 1981), and Corokiaceae (Dahlgren, 1983). In

addition, Corokia carpodetoides was originally the basis of

a separate genus, Colmeiroa (Engler, 1928), although Smith








(1958) more recently has combined this genus with Corokia.

Similarly, the genus Argyrocalymma, endemic to New Guinea,

has been reduced to a section of the genus Carpodetus

(Engler, 1928; Reeder, 1946; Schlechter, 1914). Hydrangea

also has been divided into two sections, Hydrangea and

Cornidia (McClintock, 1957), and each of these sections has

at times been elevated to the generic level (Small and

Rydberg, 1905).


Anatomical Work on the Saxifragaceae

Early anatomical studies of the Saxifragaceae are those

of Thouvenin (1890) and Holle (1893). These workers noted

that, despite their anatomical heterogeneity, the woody

saxifragaceous genera typically share the following charac-

teristics: scalariform perforation plates, three vascular

traces at the base of a petiole, and a stomatal apparatus

without subsidiary cells. In addition, trichomes vary from

simple, unicellular to branched, multicellular or glandular,

multicellular types. Prismatic crystals, druses, raphides,

or crystal sand also occur.

Thouvenin (1890) recorded anatomical descriptions of

stems and leaves for Ixerba, Bauera, Anopterus, Abrophyllum,

and Donatia along with other mostly herbaceous Saxifraga-

ceae. He concluded that the escallonioid and brexioid gen-

era (i.e., Ixerba, Anopterus, and Abrophyllum) were a cen-

tral group and all other tribes should be arranged around

them. Donatia and two other genera of the herbaceous tribe

Saxifrageae were thought to provide a link to Brexieae








(through Roussea) because these genera possess secretary

cells in the internal portions of the cortex.

Holle (1893) emphasized the anatomy of stem, leaf, and

cork of various herbaceous and woody saxifrages including

Bauera, Anopterus, Abrophyllum, Argophyllum, Carpodetus, and

Anodopetalum. Within all of these genera, cork originates

subepidermally. Holle grouped Argophyllum and Abrophyllum

together because they lacked crystals. He also placed Car-

podetus and Anopterus relatively close together because they

possess druses and simple hairs. Anodopetalum and Bauera

were isolated from the other four genera and separated from

one another because the former has both simple crystals and

druses, while the latter only has simple crystals.

Zemann (1907) elaborated on the anatomy of Argophyllum

in her monograph of the genus. She divided Argophyllum into

two sections, Brachycalyx and Dolichocalyx, based upon the

length of the calyx relative to the corolla. Zemann also

noted that the leaves of species in section Brachycalyx

either possess a bi- to triseriate hypodermis or palisade

cells that are very short and square in transaction, whereas

the leaves of species in section Dolichocalyx lack a hypo-

dermis and possess columnar palisade cells.

In his systematic anatomical summary of the dicotyle-

dons, Solereder (1908) considered all of the above genera to

be saxifragaceous. He also included the monotypic genus

Colmeiroa among the Saxifragaceae, and noted that according

to Engler, this genus possesses two-armed trichomes.





5


Watari (1939) investigated the leaf anatomy of some

Saxifragaceae, including Ixerba, Bauera, Corokia, and

Carpodetus. Except for Bauera, these genera possess

penninerved, simple leaves, trilacunar nodal patterns and

bifacial petioles. Bauera possesses palmately compound

leaves, unilacunar nodal patterns and bifacial petioles.

In addition, the foliar vascular bundles of these genera

exhibit radial rows of xylary elements and fairly regular to

irregular starch sheaths adjacent to the pericycle (Watari,

1939). Swamy (1954) studied nodal and petiolar vasculature

of the Escallonioideae and reported unilacunar, one-trace

nodal patterns in Abrophyllum and Tetracarpaea and trilacu-

nar, three-trace nodal patterns in Ixerba, Anopterus,

Cuttsia, Argophyllum, Corokia and Carpodetus. A pentalacu-

nar nodal pattern was noted for Argophyllum laxum. Swamy

(1954) indicated that the petiole patterns were similar

among certain groups of genera with unilacunar and trilacu-

nar nodal configurations.

As part of a comparative study of the wood anatomy of

the Moraceae and alleged allies, Tippo (1938) briefly

described the wood of the Hydrangeaceae, Grossulariaceae,

sensu strict, and Escalloniaceae based upon a few species

from each family. All three families are characterized by

mostly solitary, angular, thin-walled, small-diameter pores.

Vessel elements are medium to long and have predominantly

scalariform perforation plates. Imperforate elements are

mostly tracheids and fiber-tracheids and axial parenchyma is

sparse. Xylem rays are heterogeneous with sheath cells









usually present. He concluded that a close relationship

exists between the Escalloniaceae and Grossulariaceae, and

somewhat less affinity occurs between the Escalloniaceae and

Hydrangeaceae. Also, the family Escalloniaceae is the most

advanced of these three families.

Metcalfe and Chalk (1950), in their survey of the

vegetative anatomy of the dicotyledons, did the last broad

treatment of the anatomy of the Saxifragaceae. Based upon

their anatomical summaries, they placed Bauera in the

Saxifragaceae, sensu strict, Anopterus, Abrophyllum,

Argophyllum, and Carpodetus in the Escalloniaceae, Corokia

in the Cornaceae, Anodopetalum in the Cunoniaceae, and

Donatia in the Stylidiaceae.


Anatomical Work on New Zealand Genera

Certain studies of the woody plants of New Zealand

include the genera Carpodetus, Ixerba, and Corokia (Brook,

1951; Butterfield and Meylan, 1976; Meylan and Butter-

field, 1978; Morrison, 1953; Ohtani, Meylan and Butter-

field, 1983; Patel, 1973a, 1973b; Robinson and Grigor,

1963; Sampson and McLean, 1965). Some of these studies

have provided systematic conclusions based upon anatomical

data (Brook, 1951; Patel, 1973a, 1973b). Brook (1951)

studied the vegetative anatomy of the endemic Carpodetus

serratus and supported its placement in the Escalloniaceae

because of its wide rays, vessel elements with scalariform

perforation plates, and large bordered pits in the wood

fibers. Patel (1973b) investigated the wood anatomy of the









Escalloniaceae, including Carpodetus serratus and the mono-

typic Ixerba brexioides. Both species possess narrow, angu-

lar pores, and vessel elements with scalariform perforation

plates. Xylem ray tissue is heterogenous type II. The wood

of Carpodetus, however, possesses some very wide rays,

whereas the wood of Ixerba possesses only narrow rays.

Patel (1973b) concluded that both genera belonged in the

Escalloniaceae, although Ixerba was less primitive than

Carpodetus.

Although Corokia is widely distributed in the South

Pacific Islands, its center of diversity is New Zealand

(Allan, 1961). In his study of the Cornaceae Sertorius

(1893) described the leaf and stem anatomy of two species of

Corokia. He noted, as have other workers (Eyde, 1966;

Weiss, 1890), the distinctive, multicellular, T-shaped tri-

chomes in this genus. Sertorius further described the

leaves of Corokia with their uni- to biseriate palisade

mesophylls, uniseriate epidermides, and sclerenchymatous

bundle sheaths surrounding the vascular bundles. He charac-

terized Corokia wood as fine-textured, consisting of numer-

ous, thick-walled fibers bearing circular-bordered or simple

pits and solitary, narrow, angular pores. Vessel perfora-

tions are scalariform with 10-20 thin bars per plate.

Later studies of the wood anatomy of the Cornaceae (Adams,

1949; Li and Chao, 1954; Patel, 1973a) also have provided

descriptions of some species of Corokia. Adams (1949)

placed this genus in the Cornaceae near Cornus. While Li








and Chao (1954) acknowledged some affinity between Corokia

and Cornus, they also noted a close similarity between the

wood of Corokia and the wood of Saxifragaceae. Patel

(1973a) noted septate fiber-tracheids in the wood of

Corokia, and concluded that affinities with either the

Cornaceae or the Escalloniaceae were unsatisfactory for this

problematic genus. Descriptions of the distribution and

development of anomycytic stomatal patterns on the leaves

and flowers of Corokia also have been made (Bhatnagar, 1973;

Kapil and Bhatnagar, 1974).

Eyde (1966) excluded Corokia from the Cornaceae based

upon floral morphology and anatomy. He argued for an

affinity between Corokia and Argophyllum based upon floral

anatomy and the presence of multicellular, T-shaped tri-

chomes and septate fiber-tracheids in both genera. Although

both genera are included in Engler's (1928) Saxifragaceae,

subfamily Escallonioideae, Eyde questioned the validity of

this taxonomic arrangement.

Another genus that occurs in New Zealand is Donatia.

Mildbraed (1907) used vegetative and reproductive anatomical

characteristics and traditional morphological characters to

include Donatia in the Stylidiaceae within its own sub-

family, Donatioideae. Data from floral anatomy (Carolin,

1960) and embryology (Philipson and Philipson, 1973) also

support inclusion of Donatia in the Stylidiaceae, although

Carolin discussed the possibility that this family may be

closer to the Saxifragaceae rather than the Campanulaceae to

which it is often allied (Cronquist, 1981). Other work on









the vegetative anatomy of Donatia (Chandler, 1911; Rapson,

1953) has revealed multicellular, uniseriate trichomes,

tannin cells, a lignified endodermis, vessel elements with

scalariform perforation plates and sclerenchyma associated

with the foliar veins. Based upon these data, these workers

support the separation of the Donatiaceae from the

Stylidiaceae, although they emphasize that a close taxonomic

relationship exists between these two families. Both

studies also rejected any saxifragaceous affinities for

Donatia. Carlquist (1969), however, has noted morphological

similarities between Donatia and the Saxifragaceae.


Anatomical Work on the Cunoniaceae

The family Cunoniaceae is usually regarded as a close

relative of the Saxifragaceae (Cronquist, 1981; Engler,

1928; Thorne, 1983). Recent comparative floral and vegeta-

tive anatomical studies in the Cunoniaceae (Dickison, 1975c,

1975d, 1980a, 1980b) support the inclusion of Anodopetalum

in this family but are inconclusive regarding the placement

of Bauera and Aphanopetalum. Dickison (1980a) and earlier

workers (Dadswell and Eckersley, 1935; Ingle and Dadswell,

1956) place Anodopetalum among the advanced members of the

Cunoniaceae because the wood has numerous vessels commonly

distributed in multiples with vessel elements connected by

mostly simple perforation plates and opposite to alternate

intervascular pitting. Fiber-tracheids, weakly heterogen-

eous xylem ray tissue and aggregated axial parenchyma also

are present.









Dickison (1980a, 1980b) studied the nodal and wood

anatomy of Bauera sessiliflora. The presence of unilacunar,

one-trace nodes and lack of interpetiolar stipules made an

affinity to the Cunoniaceae doubtful. Nevertheless, he

noted that the wood anatomy is not inconsistent with that

found in other advanced cunoniaceous woods. Based upon

floral anatomy, Dickison (1975b) supported the inclusion of

Bauera in the Saxifragaceae, whereas Bensel and Palser

(1975c) favored a placement in the Cunoniaceae. These work-

ers have emphasized the need for further critical study of

Bauera. Carey (1938) reported a brief anatomical descrip-

tion of the leaves of Bauera rubioides from two different

habitats, and characterized this species as sclerophyllous.

Based upon study of leaf and nodal anatomy in Aphano-

petalum, Dickison (1975c, 1980b) found no affinity of this

genus to the Cunoniaceae because of its unilacunar, one-

trace nodes, lack of stipules, leaf epidermal cells with

undulate anticlinal walls, and its scrambling viny habit.

He offered no other taxonomic placement for this genus.


Rationale for the Present Study

The Saxifragaceae, sensu lato, are certainly in need of

systematic study. Stern (1974b) asserted that our failure

to sort out plants assigned to Saxifragaceae has given rise

to various classification schemes typically based upon simi-

lar, morphological data which emphasize floral morphology.

He stated that solutions to the taxonomic problems will

develop only from analysis of new data and novel methods of









interpreting old data rather than from reworking old data

using time-worn procedures. He suggested intensive studies

in plant anatomy as one means of securing new data. The

application of comparative anatomical data to the solution

of taxonomic and phylogenetic problems in plants is well-

known (Bailey, 1944; Carlquist, 1961; Metcalfe and Chalk,

1950, 1979, 1983; Stern, Brizicky, and Eyde, 1969).

Details of vegetative anatomy, particularly wood anatomy,

have been shown to be especially useful in taxonomic and

phylogenetic interpretations of various plant groups without

bias or preconception from earlier classification systems

(Dickison, 1975a; Stern, 1978b; Tippo, 1938). A recent

application of the comparative anatomical method in the

Saxifragaceae is a study of Hydrangea (Stern, 1978a).

The purpose of this work is to provide vegetative

anatomical and morphological data, especially wood anatomy,

for twelve woody saxifragaceous genera that occur in

Australia, New Zealand, New Guinea, New Caledonia and some

smaller South Pacific islands, and to use these data, where

possible, to determine the taxonomic position and evolution-

ary relationships of these plants. Although various

anatomical studies of the Saxifragaceae have been done, a

comparative, systematic study of the vegetative anatomy of

these twelve genera is lacking. The generic level has been

chosen as the unit of study to avoid any bias from previous

classification systems. The twelve genera are listed in

Table 1 according to Engler's (1928) classification system.








This system is presented as a convenient point of reference

because it is still the most comprehensive treatment of the

Saxifragaceae. Because of the relatively similar geological

history of the above Australasian land masses (Raven and

Axelrod, 1972), these 12 genera may have undergone similar

evolutionary influences and thus may exhibit many anatomical

similarities. The present anatomical study should provide

new perspectives to aid in delineating taxonomic affinities

between and among these plants from the antipodes.










Table 1. Twelve Australasian genera
classified according to Engler (1928).
Distribution information in parentheses:
A, Australia; NC, New Caledonia; NG, New
Guinea; NZ, New Zealand; PI, Other Pacific
Islands; SA, South America; T, Tasmania.



SAXIFRAGACEAE

Subfamily Tetracarpaeoideae

Tribe Tetracarpaeeae
Tetracarpaea (T)

Subfamily Brexioideae

Tribe Brexieae
Ixerba (NZ)

Subfamily Baueroideae

Tribe Bauereae
Bauera (A,T)

Subfamily Escallonioideae

Tribe Anoptereae
Anopterus (A,T)

Tribe Cuttsieae
Cuttsia (A)
Abrophyllum (A)

Tribe Argophylleae
Argophyllum (A,NC)
Corokia (A,NZ,PI)
Carpodetus (NG,NZ)

Incertae sedis: Donatia (NZ,SA,T)

CUNONIACEAE

Tribe Spiraeanthemeae
Aphanopetalum (A)

Tribe Cunonieae
Anodopetalum (T)















MATERIALS AND METHODS

Preserved leaves, stems and wood, and dried wood of

twelve woody saxifragaceous genera from Australasia were

used in this study (Table 2). Only dried leaf and stem

material of Corokia carpodetoides was available for study.

These plant materials are part of an extensive collection of

specimens of woody Saxifragaceae gathered through collec-

tion, correspondence and exchange by Professor William Louis

Stern since the late 1960's. Collection information for

individual specimens is included in the appendix (Table 4).

The authorities for the names of the species studied are

listed in Table 2.

Standard microtechnical methods were used and are

similar to those followed by Stern, Sweitzer and Phipps

(1970), so that direct comparisons could be made between the

present study and recent studies of the woody Saxifragaceae

(Stern, 1974a, 1978a; Stern, Sweitzer and Phipps, 1970;

Styer and Stern, 1979a, 1979b). Dried wood specimens were

boiled in water to eliminate air in the tissue, and the

blocks were stored in a 50:50 mixture of 95% ethanol and

glycerin. Fluid-preserved wood specimens were washed in

water and kept in the same storage solution. Transverse,

radial, and tangential sections of unembedded wood samples

of each specimen were made with a sliding microtome.








Similar sections were prepared from a few celloidin-embedded

wood samples. Sections were stained with Heidenhain's iron

alum hematoxylin and counterstained with safranin (Johansen,

1940). Because ammoniacal iron alum dissolves oxalate

crystals (Metcalfe, 1983), a few sections were dehydrated

and mounted without staining. Wood slivers were macerated

using Jeffrey's fluid (50:50 mixture of 10% nitric acid and

10% chromic acid) and stained with safranin (Johansen,

1940). Wood sections and macerations were mounted on glass

slides with Canada balsam or Permount.

Dried leaves and stems were boiled in water to

reconstitute the tissues, fixed in a formalin-acetic acid-

alcohol solution and stored in 70% ethanol. Fluid-preserved

leaves and stems also were stored in 70% ethanol. Leaves

were cleared using 5% NaOH, washed in distilled water and

bleached with a saturated aqueous solution of chloral

hydrate (Arnott, 1959). Fully cleared leaves were washed in

distilled water, stained with safranin, dehydrated and

mounted on glass slides with Permount. Transverse and

paradermal sections of paraffin-embedded leaves were cut on

a rotary microtome, affixed to a glass slide with a modified

Haupt's adhesive (Bissing, 1974), stained with iron alum

hematoxylin and safranin and mounted with Canada balsam. A

few leaf sections were mounted unstained to detect crystals.

Freehand sections were cut of at least two nodes from a

stem and at the proximal (point of attachment to stem),

median (a midpoint on petiole), and distal (near lamina)

portions of at least two petioles. These sections were








treated with an aqueous phloroglucinol solution followed by

concentrated HC1 to demonstrate lignified regions. The

nodal regions of the stems and petioles of some specimens

also were cleared and stained using the above clearing

procedure. Species with very short nodes and small petioles

were embedded in paraffin and sectioned with a rotary

microtome. These sections were treated similarly to the

paraffin-embedded leaf sections.

Anatomical analyses of leaves, including vascular

architecture, cell and tissue types, trichomes and surface

features (i.e., stomata, hydathodes, etc.), followed the

terminology used by Hickey (1979), Metcalfe (1979),

Theobald, Krahulik and Rollins (1979), and Wilkinson (1979).

Although developmental studies were not performed, the term

biseriate epidermis was used to describe both the outermost

cell layer and the subjacent cell layer in leaves where

these two layers occur to be consistent with the terminology

of other recent studies of the woody Saxifragaceae (Stern,

1974a, 1978a; Stern, Sweitzer and Phipps, 1970; Styer and

Stern, 1979a, 1979b). Measurements were made of both the

long and short axes (length and width) of ten pairs of guard

cells for each specimen. The nodal patterns and vasculation

of the petiole were diagrammed and described following the

summaries by Howard (1979a, 1979b).

Characterization of the wood followed the diagnostic

features set forth by Tippo (1941) and the terminology

advocated by the Committee on Nomenclature, International

Association of Wood Anatomists in the Multilingual Glossary









of Terms Used in Wood Anatomy (1964). The only exception is

the use of the term marginal parenchyma in place of either

terminal or initial axial parenchyma. The following meas-

urements were made for each specimen: 1) pore distribu-

tions were percentages based upon counts taken from ten 0.2

mm2 microscopic fields; 2) tangential vessel diameters

were determined from 50 measurements taken from cross sec-

tions; 3) wall thicknesses were based upon measurements of

ten vessels and ten imperforate tracheary elements taken

from cross sections; 4) lengths of cells were based upon

measurements from end to end of 50 vessel elements and 50

imperforate tracheary elements taken from macerated wood;

5) number of bars per perforation plate were counted from

thirty scalariform perforation plates; 6) end-wall angles

of vessel elements, relative to the vertical axis of the

cell, were measured for ten cells from tangential sections

using an ocular goniometer; 7) vertical diameters of

intervascular pits were determined from ten pits viewed in

radial section; 8) length and width of xylem rays were

measured from ten rays viewed in tangential section. Unless

noted otherwise, the measurements reported below represent

an average for all the species examined in a genus.





18





Table 2. Woody saxifragaceous species from Australasia
examined anatomically: d, dried material;
p, fluid-preserved material.



SPECIES WOOD LEAVES


Abrophyllum ornans Hook. f. dp p

Anodopetalum biglandulosum A. Cunn. p p

Anopterus glandulosus Labill. dp p
Anopterus macleayanus F.v. Muell. dp p

Aphanopetalum resinosum Endl. p

Argophyllum cryptophlebum Zemann p p
Argophyllum ellipticum Labill. d
Argophyllum nullumense R.T. Baker p p

Bauera capitata Seringe p
Bauera rubioides Andr. dp p
Bauera sessiliflora F.v. Muell. dp p

Carpodetus sp. p p
Carpodetus arboreus
(K. Schum. et Lauterb.) Schltr. d
Carpodetus major Schltr. d
Carpodetus serratus J.R. & G. Forst. dp p

Corokia buddleioides A. Cunn. d
Corokia carpodetoides
(F.v. Muell.) L.S. Smith d
Corokia collenettei Riley d
Corokia macrocarpa Kirk p
Corokia virgata Turrill p
Corokia whiteana L.S. Smith d

Cuttsia viburnea F.v. Muell. dp p

Donatia novae-zelandiae Hook. f. p p

Ixerba brexioides A. Cunn. dp p

Tetracarpaea tasmannica Hook. p p















RESULTS

Tetracarpaea Hook.

Introduction

The monotypic genus Tetracarpaea was described from

specimens of T. tasmannica and placed in the Cunoniaceae by

William J. Hooker in 1840. The generic name refers to its

distinctive four carpellate apocarpous gynoecium (Hooker,

1840). The genus is endemic to and occurs throughout most

of Tasmania, but is absent from the east and northwest

floristic zones of the island (Mosley, 1974b). Plants of T.

tasmannica are small, erect bushy shrubs that commonly grow

in subalpine habitats and may attain a height of approxi-

mately one foot (Bentham, 1864). These plants bear small,

exstipulate, alternate or scattered leaves and four-merous,

hypogynous, flowers arranged in racemes.

Joseph D. Hooker (1865) positioned Tetracarpaea in his

tribe Escallonieae, while Bentham (1864) placed this genus

in his tribe Cunonieae. Both tribes are included in their

order Saxifrageae (= the modern family Saxifragaceae

[Stearn, 1965]). Engler (1890) placed Tetracarpaea in his

inclusive rosalean family Saxifragaceae, first within the

subfamily Escallonioideae, but later (1928) in its own

subfamily, Tetracarpaeoideae. Schulze-Menz (1964) and

Thorne (1976, 1983) have supported the later Englerian








treatment, but other workers have diverged from this view.

Hutchinson (1967) included Tetracarpaea in the Escallonia-

ceae of his Cunoniales, while Cronquist (1981) placed it in

his larger rosalean family, Grossulariaceae. Takhtajan

(1966, 1980) placed this genus in his Saxifragales,

initially (1966) in the monotypic Tetracarpaeaceae, but

recently (1980, 1983) in his Escalloniaceae. Airy Shaw (in

Willis, 1973) and Dahlgren (1975, 1980, 1983) also con-

sidered this genus to form the basis of a monotypic family,

and Dahlgren has tentatively placed Tetracarpaea in his

Cornales.


Observations

Tetracarpaea possesses small, ovate, serrate, alternate

leaves. The small teeth of the leaf margin are rounded.

The petiole is very short and almost indistinguishable

because the lamina tapers gradually toward the point of

attachment of leaf to stem. Venation is simple craspedo-

dromous with a prominent midrib and conspicuous secondary

veins that terminate at the leaf margin (Fig. 1). Vein

areole development is incomplete to lacking. The veinlets

are usually straight and tapered, but may be somewhat forked

(Fig. 2). Vein endings consist of two to four tracheids

with helical thickenings (Fig. 2). Infrequently these

tracheids are accompanied by fiber-tracheids with thicker

walls and oval bordered pits.

The nodal pattern is unilacunar, one-trace, and a

single collateral vascular bundle enters the base of a








petiole (Fig. 3). Two collateral bundles separate from the

midvein near the base of a petiole, and a third bundle

splits from the midvein at a midpoint in a petiole. A

median section of a petiole, therefore, shows four

collateral bundles (Fig. 3). The outermost two bundles

represent the first two bundles that diverge from the

midvein. The larger of the two, central bundles represents

the petiolar midvein, while the smaller bundle represents

the third bundle to diverge from the midvein. All four

bundles enter the lamina distally (Fig. 3).

Leaves are dorsiventral with a well-differentiated,

triseriate palisade layer and a lacunose spongy mesophyll

layer (Fig. 4). The cells of the innermost layer of the

palisade layer are sometimes shorter than the other typical-

ly columnar cells of this layer, but are distinct from the

cells of the spongy mesophyll. The spongy mesophyll has

more cell layers but is approximately the same thickness as

the palisade layer (Fig. 4). The spongy mesophyll cells

have various shapes and sizes and are loosely arranged with

numerous, large intercellular spaces. The two cell layers

adjacent to the abaxial epidermis are more tightly arranged

and have smaller and fewer intercellular spaces than the

remainder of the spongy mesophyll (Figs. 4 & 5). Druses

commonly occur in the cells of the spongy mesophyll (Fig.

6).

The small, arc-shaped vascular bundles of a leaf are

collateral (Fig. 4). Very little secondary growth is

visible within these bundles. Although bundle sheaths and








bundle sheath extensions are lacking, thick-walled abaxial

fibers are present adjacent to the primary phloem of the

midvein (Fig. 4).

Both the adaxial and abaxial epidermal layers are

uniseriate and composed of variously-shaped cells with

evenly-thickened walls (Fig. 4). In surface view these

cells also are variously-shaped (polygonal to elongate), and

possess curved, evenly thickened, anticlinal walls. Both

epidermal layers lack trichomes and are covered by a very

thick cuticle (approximately 10 um; Fig. 5).

Abundant stomata are restricted to the abaxial

epidermis, and the stomatal apparatus is anomocytic. In

surface view the guard-cell pair possesses an almost

circular outline, while the individual guard cells are

reniform. Guard-cell pairs average 30 um in length and 26

um in width (length/width ratio 1.15). In transaction the

guard cells are oval to circular and each cell bears a

prominent, cuticular horn that represents the outer ledge

overarching a stoma (Fig. 5).

In cleared leaves the marginal teeth have a tumid

appearance indicating the presence of hydathodes. A

prominent vein extends nearly to the tooth apex (Fig. 7),

but water pores associated with functional hydathodes are

not distinguishable. Apical cells of the leaf teeth stain

lighter in cleared leaves than surrounding cells which may

indicate thinner cell walls (Fig. 7). The densely stained

cytoplasm of these cells in paradermal sections of uncleared

leaves may signify that this tissue is glandular.









Tetracarpaea wood is diffuse porous with poorly

discernible growth rings (Fig. 8). The wood is very fine-

textured with numerous angular pores (range 180-445/mm2, x=

309) that have extremely small tangential diameters (range

11.7-23.4 um, x= 16) and walls 2.1-4.2 um (x=2.8) thick.

Pores are predominately solitary (80%) with radial multiples

(3%) and clusters (17%) of two to three pores resulting

mostly from overlapping vessel element end walls. Rarely

clusters of four or five pores are observed. Vessels are

difficult to distinguish from axial parenchyma in slide Aw

27721 because the parenchyma is devoid of contents, and the

slide has been stained with safranin only. Thus, counts of

the number of pores per field are greatly inflated in this

specimen. Vessel elements are of medium length (range 213-

455 um, x= 354), and very fine spiral thickenings are pres-

ent in some of these cells. Vessel element end walls are

oblique, and end-wall angles range from 0-220 (x=10).

Perforation plates are exclusively scalariform, possess 5 to

18 bars per plate (x= 8), and the perforations are com-

pletely bordered (Fig. 9). Scalariform perforation plate

bars are thick and may be branched in various ways to form a

reticulate pattern. Occasionally two scalariform perfora-

tion plates occur in a vessel element end wall. Scalari-

form, transitional to opposite intervascular pitting is

confined mostly to overlapping end walls of contiguous ves-

sel elements (Fig. 9). Pit diameter is minute and ranges

from 3.2-4.2 um (x= 3.3).








Tracheids bear circular-bordered pits with oval aper-

tures that extend slightly beyond the margins of the pit

border (Fig. 9). The diameter of these pits is similar to

that of the intervascular pits. Tracheids are extremely

short (range 325-520 um, x= 396). Tracheid walls are

relatively thick and range from 2.1-6.3 um (x= 4). Very

fine spiral thickenings are present in some of these cells

(Fig. 10).

Axial parenchyma is sparse and apotracheal diffuse or

diffuse-in-aggregates. Vessel to axial parenchyma pitting

is scalariform. No ergastic substances are noted in these

cells.

Although the xylem ray system consists of homocellular

uniseriate rays of upright cells and heterocellular uni- and

biseriate rays, uniseriate rays predominate. Most hetero-

cellular rays are biseriate (Fig. 11), although these rays

are two cells wide for only 1-4 cells of their length. Ray

height ranges from 1-17 cells (.07-.75 mm) for homocellular

rays and from 7-31 cells (.28-1.22 mm) for heterocellular

rays. Ray cells contain dark brown deposits and numerous

starch grains (Figs. 9 & 11). Perforated ray cells are

infrequent (Fig. 12), while sheath cells and crystals are

absent. Vessel to ray parenchyma pitting is opposite to

alternate. No fusion of rays is noted.






























Figure 1. Leaf of Tetracarpaea tasmannica. X10. Note
simple craspedodromous venation.

Figure 2. Vein ending of T. tasmannica. X175.

Figure 3. Transverse sections of a node (a) and proximal
(b), median (c) and distal (d) sections of a petiole of T.
tasmannica. X30.


Details: t, tracheids.


























1

I b





t C




d


























Figure 4. Transverse section of a leaf of Tetracarpaea
tasmannica. X110. Note fibers abaxial to the midvein.

Figure 5. Transverse section of the abaxial epidermis of a
leaf of T. tasmannica. X700. Note the guard-cell pair
with prominent cuticular horns (arrows).

Figure 6. Transverse section of a leaf of T. tasmannica.
X437. Note druses in the spongy mesophyll.

Figure 7. Marginal tooth of a leaf of T. tasmannica.
X110.


Details: ab, abaxial epidermis; ad, adaxial epidermis; c,
cuticle; d, druses; f, fibers; gc, guard cell; m,
midvein; pl, palisade layer; sl, spongy mesophyll layer.






























-7

c
5


Yt *^
'ij


!"/


V,


W


ab
ab


I E-I


1
L'
c;
;i
I
~C'7
/i.
u~~.


6


Aim
*'-: <& J
8 '*^


~
~7S,


;r-*
j
























Figure 8. Transverse section of the secondary xylem of
Tetracarpaea tasmannica. X175. Note solitary, angular
pores.

Figure 9. Radial section of the secondary xylem of T.
tasmannica. X437.

Figure 10. Secondary xylem of T. tasmannica. X 700. Note
tracheids with spiral thickenings (arrows).

Figure 11. Tangential section of the secondary xylem of T.
tasmannica. X175. Note uni- and biseriate rays.

Figure 12. Radial section of the secondary xylem of T.
tasmannica. X437. Note perforated ray cell with scalariform
perforation plate.


Details: p, pores; pi, pits; pc, perforated ray cell;
pp, perforation plate; r, ray parenchyma; t, tracheids;
v, vessel element.













944



I tic
b b


42.:. .1r '


As' r




tv
711 G, 04,-







C.


144

0 ON



j; ir










Ixerba A. Cunn.

Introduction

The monotypic genus Ixerba was described by A. Cunning-

ham (1839) from specimens collected in Wangaroa, New Zea-

land. He based the generic name on an anagram of Brexia

Thouars to emphasize an affinity which he believed to exist

between the two genera. Ixerba brexioides is endemic to

North Island, New Zealand and occurs throughout Aukland and

northern Hawke's Bay Districts in hilly lowland and montane

forests (Allan, 1961; Cheeseman, 1914, 1925). Plants of

Ixerba are small trees with linear, opposite, alternate, or

whorled, exstipulate leaves (Allan, 1961; Cheeseman, 1925).

The five-merous, hypogynous, flowers are arranged in pani-

cles, and the fruit is a capsule.

Various taxonomists have agreed with Cunningham's view

that Ixerba and Brexia are closely related and have placed

these genera in the subfamily Brexioideae of the Saxifraga-

ceae (Engler, 1928; Schulze-Menz, 1964; Thorne, 1976) or

the Brexiaceae (Airy Shaw in Willis, 1973; Dahlgren, 1975,

1980, 1983; Takhtajan, 1966). Hooker (1865), however,

included Ixerba in the tribe Escallonieae of the Saxifraga-

ceae, and Engler (1890) originally placed it in the Escal-

lonioideae of the Saxifragaceae. Recently, Thorne (1983)

has changed his placement of Ixerba to the Escallonioideae.

Hutchinson (1967) and Takhtajan (1980, 1983) have advocated

a position in the Escalloniaceae for Ixerba, while Cronquist

(1981) placed it in his Grossulariaceae.










Observations

Ixerba possesses narrowly oblong to elliptic, alter-

nate, opposite or whorled leaves that bear blunt, widely-

spaced crenations. Venation is semicraspedodromous with a

prominent midrib and conspicuous secondary veins that branch

to extend near the leaf margin and arch distally to join

with superadjacent secondary veins (Fig. 13). Vein areole

development is incomplete. Veinlets vary, from simple and

straight to once, twice, or three times branched (Fig. 14).

The vein endings may be branched or unbranched and tapered,

and are composed of helically thickened tracheids that may

be elongate, curved, forked, or irregularly shaped (Fig.

14). These tracheids often possess protuberances which are

characterized by helical thickenings that differ in orienta-

tion from the thickenings in the remainder of the cell.

Parenchymatous bundle-sheath cells and thick-walled fibers

are associated with the vascular tissues in most vein

endings.

The nodal pattern is trilacunar, three-trace, and three

collateral bundles enter a petiole (Fig. 15). These bundles

fuse laterally to produce a single, large flattened bundle

in the center of the petiole in median and distal sections

(Fig. 15). In some petioles a median section reveals that

one lateral bundle fuses with the central bundle before the

other lateral bundle. In these latter petioles the large

flattened bundle is only visible in more distal sections of

the petiole. A very small collateral bundle splits from









each end of the large central petiolar bundle. These small

accessory bundles occur lateral to the central bundle (Fig.

15).

Leaves of Ixerba are dorsiventral with a well-

developed, bi- to triseriate palisade layer and a highly

lacunose spongy mesophyll layer (Fig. 16). The two upper-

most layers of palisade cells are typically columnar and

tightly appressed, while the cells of the innermost layer

are highly variable in shape, often widely-spaced, and

intergrade with the adjacent spongy mesophyll cells (Fig.

16). The cells of the spongy mesophyll are highly variable

in shape and size and separated by numerous, large inter-

cellular spaces. One or two large, yellowish, optically

anisotropic, crystalloid inclusions occur in most cells of

the palisade and spongy layers and both epidermides (Figs.

16 & 17). These inclusions probably are not calcium oxalate

crystals because they did not dissolve in ammoniacal iron

alum.

All vascular bundles of a leaf are collateral and

surrounded by a bundle sheath. The large, flattened, arc-

shaped, midvein, with well-developed secondary growth, is

almost completely surrounded by thick-walled, lignified

parenchyma cells (Fig. 18). This large bundle also posses-

ses adaxial and abaxial bundle sheath extensions composed of

parenchyma and collenchyma cells. The smaller vascular

bundles (secondary and minor veins) exhibit no secondary

growth, have a few sclerenchyma cells adjacent to the








primary vascular tissues, are surrounded by a parenchymatous

bundle sheath and lack bundle sheath extensions (Fig. 16).

Both the adaxial and abaxial epidermal layers are

uniseriate, and consist of mostly square to rectangular

cells in transaction (Fig. 16). The outer periclinal walls

of all epidermal cells are slightly thickened. In surface

view the epidermal cells are square to polyhedral with

straight anticlinal walls. The cuticle is very thick (>5

um), and trichomes are absent.

Abundant stomata are restricted to the abaxial epider-

mis, and the stomatal apparatus is anomocytic (Fig. 19). In

surface view guard cells are reniform, and guard-cell pairs

are virtually circular in outline with an average length of

36 um and a width of 34 um (length/width ratio 1.06). In

transaction guard cells are oval, and each cell bears a

small, thin, cuticular horn that represents the outer ledge

overarching a stoma (Fig. 20).

Marginal crenations of Ixerba leaves contain glands

that are characterized by thick-walled parenchyma cells

arranged in regular files (Fig. 21). In paradermal sections

of uncleared leaves, the cytoplasm of these cells is very

dense and stains very darkly (Fig. 22). Each creation is

supplied by an arc of vascular tissue that is derived from

the union of two secondary or tertiary veins (Fig. 21).

Wood of Ixerba is diffuse porous and exhibits distinct

growth rings (Fig. 23). The wood is fine-textured with very

numerous angular pores (range 70-235/mm2, x= 114) that

possess thin radial walls (range 1.1-3.7 um, x= 1.9) and








very small tangential diameters (range 25-55 um, x=41). The

pores are predominantly solitary (76%), although radial

multiples of two pores (2%) and clusters of two to five

pores (22%) mostly due to overlapping end walls of vessel

elements do occur. Vessel elements are long and range from

617-1600 um (2= 1149). Vessel elements possess oblique end

walls with angles ranging from 2-180 (x= 8) and lack spiral

thickenings. Perforation plates are exclusively scalariform

with 16-71 thin bars per plate (x= 40) (Fig. 24). One

specimen (Aw H-20087) of Ixerba was distinct from all the

others because of its exceptionally long vessel elements

(range 1117-1942 um, x= 1498) and very numerous bars per

scalariform perforation plate (range 47-111, x=71).

Although perforations typically lack borders, perforations

with borders at the ends or rarely with complete borders may

be found in the narrowest vessel elements. Intervascular

pitting is extremely rare and confined to overlapping vessel

element end walls. When present, round to oval pits with

small diameters (range 3.7-5.3 um, x= 4.5) typically occur

in uniseriate files (Fig. 24).

Tracheids bear circular-bordered pits with oval inner

apertures that may be included within or extend beyond the

margins of the pit border (Fig. 24). The diameter of these

pits is similar to that of the intervascular pits. Trache-

ids are medium to moderately long (range 867-2084 um, x=

1438), with relatively thin radial walls (range 2.6-8.9 um,

x= 4.7), and fine or coarse spiral thickenings occasionally

are present.









Axial parenchyma is sparse and predominantly apotra-

cheal diffuse and paratracheal scanty, although diffuse-in-

aggregates parenchyma may also occur. Vessel to axial pa-

renchyma pitting is mostly transitional or opposite, rarely

alternate. No ergastic substances are noted in these cells.

The xylem ray system predominantly is composed of homo-

cellular, uniseriate rays of upright cells and heterocellu-

lar, bi- and multiseriate rays (Fig. 25). Most heterocellu-

lar rays are biseriate, although some may be uniseriate.

Ray height ranges from 1-15 cells (.06-1.03 mm) for homocel-

lular rays, 8-27 cells (.25-1.18 mm) for heterocellular

uniseriate rays, and 6-52 cells (.25-2.00 mm) for heterocel-

lular bi- and multiseriate rays. Heterocellular rays range

from 2-4 cells (26-70 um) wide. Very few ray cells contain

dark brown deposits, and crystals are absent. Sheath cells

are absent, while perforated ray cells with scalariform or

reticulate perforation plates commonly occur in some speci-

mens (Fig. 26). The pitting between vessels and ray paren-

chyma and vessels and axial parenchyma is mostly transition-

al to opposite. All types of rays may be fused end-to-end.





























Figure 13. Leaf of Ixerba brexioides. Xl. Note marginal
crenations and semicraspedodromous venation.

Figure 14. Vein ending of I. brexioides. X175.

Figure 15. Transverse sections of a node (a) and the
proximal (b), median (c) and distal (d) sections of a
petiole of I. brexioides.


Details: f, fibers; t, tracheids.






























13
""%,e


15


Te
























Figure 16. Transverse section of a leaf of Ixerba
brexioides. X175.

Figure 17. Optically anisotropic crystalloid from a leaf of
I. brexioides. X700.

FIgure 18. Transverse section of the midvein of a leaf of
I. brexioides. X110.

Figure 19. Paradermal section of the abaxial epidermis of a
leaf of I. brexioides. X437. Note anomocytic stomatal
apparatus.

Figure 20. Transverse section of the abaxial epidermis of a
leaf of I. brexioides. X700. Note the guard cells with
small cuticular horns (arrows).


Details: ab, abaxial epidermis; ad, adaxial epidermis; b,
bundle sheath; be, abaxial bundle sheath extension; be',
adaxial bundle sheath extension; c, cuticle; cr, crystal-
loid; gc, guard cells; Ip, lignified parenchyma; pl,
palisade layer; sl, spongy mesophyll layer ; st, stoma;
vb, vascular bundle.


























Figure 21. Marginal creation of a leaf of Ixerba
brexioides. X110. Note the arc of vascular tissue.

Figure 22. Paradermal section of a marginal creation of a
leaf of I. brexioides. X110. Note apical gland.

Figure 23. Transverse section of the secondary xylem of I.
brexioides. X110. Note solitary, angular pores.

Figure 24. Radial section of the secondary xylem of I.
brexioides. X437.

Figure 25. Tangential section of the secondary xylem of I.
brexioides. X110. Note uni- and biserate rays.

Figure 26. Radial section of the secondary xylem of I.
brexioides. X437. Note the perforated ray cell with
scalariform perforation plate.


Details: g, gland; p, pore; pc, perforated ray cell; pi,
pits; pp, perforation plate; r, ray parenchyma; t,
tracheid; v, vessel element; vt, vascular tissue.















Bauera Banks

Introduction

The genus Bauera was named by Sir Joseph Banks and

described from specimens of B. rubioides in 1801 (Bailey,

1900; Bentham, 1864; Black, 1924; Burbidge, 1963;

Willis, 1972). The generic name commemorates the botanical

artists Francis and Ferdinand Bauer (Bailey, 1900; Black,

1924). The three species of this genus are endemic to

southeastern Australia and Tasmania. Bauera rubioides, the

most widespread species, occurs in wet places throughout

Tasmania, eastern Victoria, eastern New South Wales and

southeastern Queensland (Black, 1924; Bailey, 1900;

Bentham, 1864; Willis, 1972). This species is rare on

Kangaroo Island in South Australia (Mosley, 1974a). Bauera

capitata occurs in southeastern New South Wales and Fraser's

Island off the coast of southeastern Queensland (Bailey,

1900; Bentham, 1864). Bauera sessiliflora is restricted to

the Grampian Mountain range in western Victoria. Plants of

Bauera are either prostrate or upright shrubs up to 2 m

tall. All species of Bauera reportedly bear opposite, ses-

sile, exstipulate, three-foliolate leaves which give the

appearance of a whorl of six leaves (Bailey, 1900; Bentham,

1864). Although flowers may have four to ten sepals and

petals, most flowers have five to nine sepals and petals

(Bailey, 1900; Bentham, 1864; Dickison, 1975b). Each

flower possesses a few to many stamens and contains a









superior to half-inferior, bicarpellate, syncarpous gynoe-

cium that ripens into a capsule. Bauera is commonly grown

as a greenhouse shrub (Bailey, 1944; Bailey and Bailey,

1976; Synge, 1974).

Although Hooker (1865) considered Bauera an anomalous

genus within the Saxifragaceae, Bentham (1864) placed it in

the tribe Cunonieae of the Saxifragaceae. Two recent work-

ers (Cronquist, 1981; Takhtajan, 1980, 1983) have placed

this genus in the Cunoniaceae, and have aligned this family

within either the order Grossulariales or Saxifragales,

respectively. Other systematists have placed Bauera in the

monogeneric subfamily Baueroideae of the Saxifragaceae

(Engler, 1890, 1928; Schulze-Menz 1964; Thorne, 1976), and

included this family in the Rosales. Thorne (1983), how-

ever, recently has placed this genus in the monogeneric

family Baueraceae, as have other workers (Airy Shaw in

Willis, 1973; Dahlgren, 1975, 1980, 1983; Hutchinson,

1967), and they all place the Baueraceae among the

Cunoniales.

Wood, nodes and leaves of B. rubioides and B.

sessiliflora, and nodes and leaves of B. capitata were

available for study (Table 2). Unless noted otherwise, data

apply to all species examined.


Observations

Bauera typically possesses simple, opposite, petiolate

leaves, although B. rubioides may have whorled leaves. Each

leaf is accompanied laterally by two large stipules that are









morphologically and anatomically similar to the leaves.

Each stipule is attached to the stem by a very short stalk.

Leaves of B. rubioides and B. sessiliflora are elliptic or

ovate with entire to obscurely toothed margins (Fig. 27).

Leaves of B. capitata may be elliptic or two- to three-lobed

(Fig. 28). Venation is semicraspedodromous to brochido-

dromous in B. rubioides and B. sessiliflora with a prominent

midvein and conspicuous secondary veins that either extend

to the leaf margin and/or form arches with superadjacent

secondary veins (Fig. 27). Venation is mixed craspedo-

dromous in B. capitata with some secondary veins that extend

to the leaf margin and others that arch distally to join

with superadjacent secondary veins (Fig. 28). Vein areole

development is incomplete in B. sessiliflora and lacking in

both B. rubioides and B. capitata. Veinlets typically are

forked or branched. Most tracheids of a vein ending are

elongate and slender with helical thickenings, while the

terminal tracheids of a vein ending usually are shorter,

larger in diameter and thicker-walled than the elongate

tracheids (Fig. 29). The terminal tracheids have reticulate

wall thickenings and may possess short protuberances.

The nodal pattern is unilacunar, one-trace, and this

leaf trace quickly splits twice to form three traces, each

of which is a collateral bundle (Fig. 30). The median trace

enters a leaf, and each of the lateral traces enters a

lateral, foliaceous stipule. These bundles traverse the

length of a short petiole or stipular stalk (Fig. 30). At








approximately the same level as the trifurcation of the leaf

trace in the stem, two branch traces arise and quickly fuse

to form a cylindrical stele in the branch opposite a simple

leaf (Fig. 30).

Leaves of Bauera are dorsiventral with a well-

differentiated, uni- to biseriate palisade layer and a high-

ly lacunose spongy mesophyll layer (Fig. 31). The palisade

cells typically are elongate and columnar, but may be short

and oval in transaction. These cells may be tightly ap-

pressed or loosely arranged with small intercellular spaces.

The cells of the spongy mesophyll have various shapes and

sizes and are separated by numerous, large intercellular

spaces. Prismatic crystals are common in the spongy meso-

phyll cells, especially near a vascular bundle (Fig. 32).

The oval or round vascular bundles of Bauera leaves are

collateral, and only the midvein exhibits a small amount of

secondary growth. Although bundle sheaths and bundle sheath

extensions are absent, thick-walled fibers commonly occur

adjacent to the primary vascular tissues of each bundle

(Fig. 31).

The abaxial epidermis in all species is exclusively

uniseriate and composed of very narrow, thick-walled cells

in transaction. The adaxial epidermis is uniseriate (B.

capitata and B. rubioides) or biseriate (B. rubioides and B.

sessiliflora). In the latter species the cells of the

outermost layer of the adaxial epidermis resemble those of

the abaxial epidermis, while the cells of the innermost

layer are composed of very large, thin-walled cells









(Fig. 33). These latter cells are very delicate and often

become distorted and disintegrate when sectioned (Fig. 34).

In surface view the cells of both the abaxial epidermis and

the outermost layer of the adaxial epidermis are variously

shaped and possess sinuous or curved anticlinal walls.

Although the cuticle is thin (<5 um) in all three species,

it is slightly thicker on the abaxial surface of a leaf.

Numerous stomata are restricted to the abaxial epider-

mis. The stomatal apparatus is anomocytic, although the

three or four subsidiary cells which surround a guard-cell

pair are smaller than the other epidermal cells (Fig. 35).

In surface view individual guard cells are reniform, and

guard-cell pairs are elliptic to circular in outline (Fig.

35). Guard-cell-pair length averages 32 um and width aver-

ages 29 um (length/width ratio 1.10). In transaction guard

cells are oval, and each cell bears a large cuticular horn

that represents the outer ledge overarching a stoma (Fig.

36). Unicellular, thick-walled, lignified trichomes with

tapered ends are abundant on both epidermal layers and

along the margins of leaves of B. rubioides and B. sessili-

flora, but are sparse on the leaves of B. capitata (Fig.

37). The base of each trichome is surrounded by a ring of

epidermal cells which are much larger than the surrounding

epidermal cells (Figs. 33 & 34). One or two adaxial epider-

mal cells along most of the margin of the leaves of B.

capitata are expanded into a ridge which appears as an

elongate or clavate protrusion in transaction (Fig. 38).









The apex and marginal teeth of a leaf possess thick-

walled cells with darkly staining cytoplasm that resemble

glandular cells (Fig. 37).

Although the wood of the two species of Bauera studied

is very similar, B. sessiliflora has longer vessel elements

and tracheids and taller rays than B. rubioides. Distinct

growth layers occur in the wood of both species. The wood

of B. rubioides is diffuse porous while the wood of B.

sessiliflora is ring porous (Fig. 39). Both species pos-

sess very numerous pores, with ranges of 270-385/mm2 (=

325) for B. rubioides and 185-320/mm2 (x= 257) for B. ses-

siliflora. Both species have thin-walled (range 1.1-4.2 um,

x= 2.0) angular pores with very small tangential diameters

(range 18-57 um, x= 37). Pores are predominantly solitary

(84%), although true radial multiples (3%) and clusters

(13%) do occur. Vessel elements are medium length, however,

those of B. sessiliflora (range 234-780 um, x= 523) are

longer than those of B. rubioides (range 208-579 um, x=

383). Vessel element end walls vary from transverse to

oblique, with end-wall angles that range from 22-900 (x=

39). Perforation plates are typically simple, however sca-

lariform perforation plates with 1-5 thin bars may occur in

both species (Fig. 40). All perforations lack borders.

Very fine spiral thickenings rarely occur in the vessel

elements of B. sessiliflora only. Intervascular pitting

usually is scalariform or transitional in both species,

although opposite or alternate patterns rarely occur








(Fig. 40). The diameter of the elongate or oval pits is

minute (range 3.2-7.4 um, x= 4.7).

Tracheids of both species bear circular-bordered pits

with oval inner apertures that are included within the pit

border (Fig. 41). The diameter of these pits is similar to

that of the intervascular pits. The tracheids of both

species are very short, although those of B. sessiliflora

are longer (range 436-956 um, x= 721) than those of B.

rubioides (range 312-650 um, x= 484). These tracheids have

relatively thin radial walls (range 2.6-5.3 um, x= 3.7) and

fine spiral thickenings.

Axial parenchyma is sparse and either apotracheal dif-

fuse or paratracheal scanty. Vessel to axial parenchyma

pitting is not visible in the material examined. Dark brown

deposits commonly occur in these cells.

The xylem ray system is composed mostly of homocellu-

lar, uniseriate rays of upright or square cells and a few

heterocellular, bi- and multiseriate rays (Fig. 42). Homo-

cellular, biseriate and heterocellular, uniseriate rays are

rare. The homocellular rays are slightly taller in B.

sessiliflora (1-14 cells, 0.11-0.81 mm) than in B. rubioides

(1-6 cells, 0.04-0.31 mm). Although heterocellular rays

also are taller in B. sessiliflora (18-84 cells, 0.50-1.89

mm) than in B. rubioides (19-61 cells, 0.32-0.98 mm), the

width of these rays is similar in both species (2-7 cells,

18-75 um). Dark brown deposits commonly occur in the ray

cells of both species (Fig. 40). Sheath cells are absent,

while perforated ray cells with simple or foraminate





50



perforation plates are occasionally present (Fig. 41). Ves-

sel to ray parenchyma pitting is scalariform to fenestri-

form. Both homocellular and heterocellular rays may be

fused end-to-end.


































Figure 27. Leaf of Bauera rubioides. X10. Note
semicraspedodromous to brochidodromous venation.

Figure 28. Diversity of leaf shapes in B. capitata. X10.

Figure 29. Vein ending of B. rubioides. X437. Note
helically thickened tracheids.


Details: t, tracheids.


=0010i

























27 28




t







29 '





























Figure 30. Diagrammatic representation of a node and the
nodal pattern of Bauera rubioides. X30. Leaves and
stipules are not drawn to scale.


Details:
stipule;


BT, branch trace; L, leaf; LT, leaf trace; S,
ST, stipular traces.










cn I-

Cl)
U C, Cv ,



/o







0, 0C














Cl
S0

QCt



















Figure 31. Transverse section of a leaf of Bauera capitata.
X175.

Figure 32. Transverse section of a leaf of B. capitata
showing prismatic crystals near a vascular bundle. X700.

Figure 33. Transverse section of a leaf of B. sessiliflora.
X110.

Figure 34. Transverse section of a leaf of B. sessiliflora.
X110.

Figure 35. Paradermal section of the abaxial epidermis of a
leaf of B. rubioides. X437. Note anomocytic stomatal
apparatus.

Figure 36. Transverse section of the abaxial epidermis of a
leaf of B. capitata. X700. Note the guard cells with
prominent cuticular horns (arrows).

Figure 37. Marginal serration of a leaf of B. rubioides.
X175. Note marginal trichome.

Figure 38. Transverse section of a leaf of B. capitata.
X175. Note the protrusion (arrow) that represents a ridge
of cells along the adaxial margin of a leaf.


Details: ab, abaxial epidermis; ad, adaxial epidermis; c,
cuticle; cr, crystal; e, enlarged epidermal cells; f,
fibers; g, gland; gc, guard cells; m, midvein;; pl,
palisade layer; sl, spongy mesophyll layer; st, stoma;
tr, trichome.
















ad ad



e


34


tr


33


























Figure 39. Transverse section of the secondary xylem of
Bauera rubioides. X110. Note boundary of growth ring
(arrow) and solitary, angular pores.


Figure 40.
rubioides.


Radial section of the secondary xylem of B.
X175.


Figure 41. Radial section of the secondary xylem of B.
sessiliflora. X437. Note tracheids with circular-bord-ered
pits and perforated ray cell with a simple perforation
plate.

Figure 42. Tangential section of the secondary xylem of B.
sessiliflora. X110. Note uni-, bi- and multiseriate rays.


Details: p, pore;
perforation plate;
element;


pc, perforated ray cell; pi, pits; pp,
r, ray; t, tracheid; v, vessel















Anopterus Labill.


Introduction

Anopterus was described from specimens of A. glandu-

losus by J.-J. Labillardiere in 1804. The generic name

refers to the broad, membranaceous wing on the end of each

seed produced by these plants (Bailey, 1900). The type

species is endemic to Tasmania where it is widespread

throughout the island, especially in subalpine forests

(Bentham, 1864; Mosely, 1974b). The only other species in

the genus, A. macleayanus, is endemic to eastern and south-

eastern Queensland and northeastern New South Wales, Austra-

lia where it occurs up to elevations of 1500 m (Bailey,

1900; Bentham, 1864; Burbidge, 1963). Plants within the

genus are shrubs or small trees with alternate, simple,

exstipulate leaves (Bailey, 1900; Bentham, 1864). The six-

to nine-merous flowers are borne in racemes, and each con-

tains a bicarpellate, superior ovary that ripens into a

capsule. Anopterus glandulosus commonly is used in ornamen-

tal horticulture for its handsome evergreen foliage (Bailey

1944; Bailey and Bailey, 1976; Synge, 1974).

Most taxonomists have placed Anopterus in either the

Saxifragaceae, subfamily Escallonioideae (Engler, 1890,

1928; Schulze-Menz 1964; Thorne, 1976, 1983) or the Escal-

loniaceae (Airy Shaw in Willis, 1973; Dahlgren, 1975, 1980,

1983; Takhtajan, 1980, 1983). Cronquist (1981), however,








included this genus in his Grossulariaceae. Although most

of these systematists have included these taxa in the

Rosales or some roughly equivalent order, some workers have

placed them in either the Cunoniales (Hutchinson, 1967) or

the Cornales (Dahlgren, 1975, 1980, 1983).

Wood, leaves, and nodes of A. glandulosus and A.

macleayanus were examined in this study (Table 2). Unless

noted otherwise, data apply to both species.


Observations

Anopterus macleayanus possesses very long, narrowly

oblanceolate to oblanceolate leaves while A. glandulosus

possesses smaller, oblanceolate leaves. The leaves of both

species bear blunt crenations (Fig. 43). Venation is semi-

craspedodromous with a prominent midvein and conspicuous

secondary veins whose branches extend near the leaf margin

and arch distally to join with superadjacent secondary or

tertiary veins (Fig. 43). Vein areoles are smaller and

their development is imperfect in A. macleayanus, while they

are larger and their development is incomplete in A. glandu-

losus. Veinlets vary from straight to once or twice

branched. Vein endings are usually tapered and simple, but

may be clavate or branched. These vein endings are composed

of two to eight helically thickened tracheids that usually

are elongate but, may have irregular shapes (Fig. 44). Some

tracheids possess small protuberances on their side walls

that are characterized by helical thickenings that differ in

orientation from the thickenings in the remainder of the








cell. These protuberances are less common in A. macleayanus

than in A. glandulosus. In the latter species they often

correspond to the interface between two large, irregularly

shaped bundle sheath cells. Bundle sheath cells are not

visible in the vein endings of A. macleayanus.

Although the nodal pattern is trilacunar, three-trace

in Anopterus (Fig. 45), the vasculature of the petiole is

very different for the two species (Figs. 46 & 47). In A.

glandulosus, three collateral bundles enter the base of a

petiole, traverse its entire length and enter the lamina

distally (Fig. 46). Three bundles also enter the base of a

petiole in A. macleayanus (Fig. 47). However, only the

middle bundle is collateral, while the two lateral bundles

are amphicribral (Fig. 47). Near the base of a petiole in

A. macleayanus, the middle, collateral bundle enlarges to

form a horseshoe-shaped or concentric central bundle with

the two lateral, amphicribral bundles on either side. In

the proximal half of a petiole two large gaps form in the

large central bundle opposite the lateral amphicribral bun-

dles. The central bundle also may divide at positions other

than opposite the lateral bundles. Near a median point on a

petiole the two amphicribral bundles become collateral and

arc-shaped with xylem internal, and each of these bundles

fuses with the dissected central bundle (Fig. 47). All of

the remaining bundles of the dissected central bundle fuse

to form a large horseshoe-shaped bundle that enters the

lamina distally (Fig. 47).








Leaves of Anopterus are dorsiventral with a narrow,

typically uniseriate, rarely biseriate palisade layer and a

lacunose spongy mesophyll layer (Fig. 48). The uppermost

cells of the palisade layer are elongate and tightly

appressed while the lowermost cells are shorter and more

loosely arranged. These latter cells are typically inter-

mingled with the spongy mesophyll cells. The elongate

uppermost palisade cells of A. glandulosus are somewhat

longer than those of A. macleayanus. The spongy mesophyll

cells have various shapes and sizes and are separated by

large intercellular spaces. Druses are common in the spongy

mesophyll cells of A. macleayanus, but infrequently occur in

A. glandulosus.

The vascular bundles of a leaf typically are collat-

eral, however, certain bundles (secondary veins) in A. mac-

leayanus are amphicribral. The midvein and larger bundles

(secondary veins) of both species exhibit a moderate amount

of secondary growth. The midvein of A. glandulosus is

relatively small and flattened or arc-shaped (Fig. 49),

whereas that of A. macleayanus is very large and horseshoe-

shaped (Fig. 50). In A. glandulosus the midvein is sur-

rounded by thick-walled, lignified parenchyma cells adaxial-

ly and thin-walled parenchyma cells abaxially. Bundle

sheath extensions of large diameter, thick-walled, unligni-

fied parenchyma cells occur abaxially and adaxially. The

larger bundles in this species have thick-walled fibers

adjacent to the primary phloem, and all vascular bundles,

except the midvein, are surrounded by parenchymatous bundle








sheaths without bundle sheath extensions. In A. macleayanus

thick-walled fibers occur adjacent to the primary phloem of

the large midvein and the amphicribral bundles (secondary

veins) (Fig. 50). The ground tissue adjacent to the primary

xylem and abaxial to the midvein consists of large diameter

parenchyma cells (Fig. 50). Smaller, thicker-walled, unlig-

nified parenchyma cells occur adaxially to these large diam-

eter parenchyma cells. The smaller bundles (minor veins) in

A. macleayanus lack bundle sheaths and extensions.

Both epidermal layers are uniseriate, and their cells

have various shapes in transaction (Fig. 48). The cell

walls of the epidermal cells are slightly thicker than those

of the mesophyll cells. In surface view epidermal cells are

variously shaped and generally possess sinuous anticlinal

walls, although the abaxial epidermal cells of A. glandu-

losus may have curved anticlinal walls. The cuticle is thin

(<5 um) and trichomes are absent.

Numerous stomata are restricted to the abaxial epider-

mis, and the stomatal apparatus is anomocytic. In surface

view guard cells are reniform and guard-cell pairs are

virtually circular in outline. Guard-cell pairs have an

average length of 36 um and a width of 34.5 um (length/width

ratio 1.04) in A. glandulosus, while those of A. macleayanus

have an average length of 31 um and a width of 33 um

(length/width ratio .94). In transaction guard cells are

oval and thick-walled, and each cell bears a short, curved

cuticular horn that represents the outer ledge overarching

the stoma (Fig. 51).









The apex and marginal crenations of Anopterus leaves

contain glands at their apices. In leaf clearings these

glands are characterized by dark-staining, thick-walled

parenchyma cells arranged in regular files (Fig. 52). In

paradermal sections of uncleared leaves, the cytoplasm of

these cells is very dense and stains very darkly (Fig. 53).

Each marginal creation is supplied by an arc of vascular

tissue that is derived from the union of two or more

secondary or tertiary veins (Fig. 52).

The wood of Anopterus exhibits distinct growth rings

(Fig. 54). The wood of A. macleayanus is exclusively dif-

fuse porous. While wood of A. glandulosus is mostly semi-

ring porous, it also may be diffuse porous. Anopterus wood

is fine-textured with very numerous angular pores (range 60-

210/mm2, x= 128) that possess very small tangential diame-

ters. Pores of A. glandulosus are narrower (range 25-47 um,

x= 37) than those of A. macleayanus (range 26-68 um, x= 48).

In both species pore distribution is mostly solitary (78%),

although radial multiples of two to three cells (2%) and

clusters of two to five cells (20%), mostly due to overlap-

ping end walls of vessel elements, do occur (Fig. 54). The

vessel elements of both species have very thin radial walls

(range 1.1-3.7 um, x= 2.4) and lack spiral thickenings.

These cells are long in both species, although they are

longer in A. macleayanus (range 667-2084 um, x= 1220) than

in A. glandulosus (range 483-1634 um, x= 1023). Vessel

elements possess oblique end walls with angles that range








from 3-210 (x= 10). Perforation plates are exclusively

scalariform with 7-44 bars per plate (x= 24) (Fig. 55).

Bars are thin and often forked or branched. Occasionally

two scalariform perforation plates occur per oblique vessel

element end wall. Perforations commonly lack a border,

however, in the narrowest vessel elements they may be bor-

dered at the ends or completely bordered. Only one specimen

of A. glandulosus (F. M. Hueber 3/17/70) possesses a few

thin-walled tyloses in some vessels and trabeculae in some

vessels and tracheids. This specimen also is the only one

with abundant fungal hyphae throughout the wood. Intervas-

cular pitting is uncommon in Anopterus, but, when present,

these pits are very irregular and confined to overlapping

end walls (Fig. 55). Intervascular pitting may be scalari-

form, transitional, opposite, or alternate, although transi-

tional and opposite are the most common patterns. These

elongate or oval pits have minute to small diameters (range

3.2-7.4 um, x= 5.0).

Tracheids bear circular-bordered pits with oval to

slit-like inner apertures that may be included within or

extend beyond the margins of the pit border. The diameter

of these pits is similar to that of the intervascular pits.

Tracheids are medium to moderately long, and these cells in

A. macleayanus are slightly longer (range 984-2134 um, x

1465) than those in A. glandulosus (range 1000-1734 um, x=

1315). These tracheary elements have relatively thick

radial walls (range 3.2-7.4 um, x= 5.2) and fine spiral

thickenings (Fig. 55).









Axial parenchyma is sparse and predominantly apotra-

cheal diffuse, although a few cells may be paratracheal

scanty, or apotracheal marginal at the beginning of a

growth layer. Vessel to axial parenchyma pitting, although

rarely seen, is transitional, opposite, or alternate. No

ergastic substances are noted in these cells.

The xylem ray system is composed of homocellular, uni-

seriate rays of upright cells and heterocellular, bi- and

multiseriate rays (Fig. 56). One very young specimen of A.

macleayanus has a few heterocellular, uniseriate rays.

Homocellular rays are 1-20 cells high (.10-2.83 mm) for both

species of Anopterus. Heterocellular rays are taller in A.

glandulosus (7-53 cells, .37-3.97 mm) than in A. macleayanus

(height: 7-37 cells, .33-2.63 mm). Heterocellular rays are

also a bit wider in A. glandulosus (2-10 cells, 31-187 um)

than in A. macleayanus (2-3 cells, 44-62 um). These differ-

ences in width are relatively minor because most heterocel-

lular rays are 2-4 cells wide in both species. Dark brown

deposits and starch grains are present in some ray cells.

Sheath cells are absent, while perforated ray cells with

scalariform perforation plates are occasionally present in

both species (Fig. 57). Vessel to ray parenchyma pitting is

transitional to mostly opposite, or alternate. All types of

rays may be fused end-to-end, and all types may be split by

vessels and/or tracheids.




























Figure 43. Leaf of Anopterus glandulosus. Xl. Note
marginal crenations and semicraspedodromous venation.

Figure 44. Vein ending of A. glandulosus. X175.

Figure 45. Transverse section of a node of A. glandulosus.
X10.

Figure 46. Transverse sections of proximal (a), median (b)
and distal (c) sections of a petiole of A. glandulosus.
X10.

Figure 47. Transverse sections of proximal (a), median
(b) and distal (c) sections of a petiole of A. macleayanus.
X10.


Details: t, tracheids.























45






a






b







46 47
. 46 47


a


43
4,
-I


, I~
A U~c

-1 'K


b




















Figure 48. Transverse section of a leaf of Anopterus
glandulosus. X110.

Figure 49. Transverse section of the midvein of a leaf of
A. glandulosus. X46.

Figure 50. Transverse section of the midvein of a leaf of
A. macleayanus. X46. Note secondary vein.

Figure 51. Transverse section of the abaxial epidermis of a
leaf of A. glandulosus. X700. Note guard cells with small
cuticular horns (arrows).

Figure 52. Marginal creation of a leaf of A. glandulosus.
X110. Note the arc of vascular tissue which vascularizes
the creation.

Figure 53. Paradermal section of a marginal creation of a
leaf of A. glandulosus. X110.


Details: ab, abaxial epidermis; ad, adaxial epidermis; b,
bundle sheath; be, abaxial bundel sheath extension; be',
adaxial bundle sheath extension; c, cuticle; f, fiber; g,
gland; gc, guard cells; gt, ground tissue; pl, palisade
layer; sl, spongy mesophyll layer; sv, secondary vein;
vb, vascular bundle; vt, vascular tissue.























































53
m '^



























Figure 54. Transverse section of the secondary xylem of
Anopterus glandulosus. X110. Note boundary of growth ring
(arrow) and solitary, angular pores.

Figure 55. Radial section of the secondary xylem of A.
glandulosus. X437. Note spiral thickenings (arrow) in
tracheids.

Figure 56. Tangential section of the secondary xylem of A.
glandulosus. Xll0. Note uni-, bi- and multiseriate rays.

Figure 57. Radial section of the secondary xylem of A.
glandulosus. X437. Note perforated ray cell with
scalariform perforation plate. X437.


Details: p, pore; pc, perforated ray cell; pi, pits; pp,
perforation plate; r, ray; t, tracheid;















Cuttsia F. v. Muell.

Introduction

The monotypic genus Cuttsia was described by Ferdinand

von Mueller in 1865 from specimens of C. viburnea. The

generic name commemorates J. Cutts, the treasurer of the

"Ladies Leichhardt Search Expedition," a group of women who

raised money to support a search expedition to account for

the disappearance of Ludwig Leichhardt (Mueller, 1865;

Willis, 1949). This genus is endemic to southeastern

Queensland and northeastern New South Wales, Australia and

occurs along mountain streams (Bailey, 1900; Burbridge,

1963). Cuttsia viburnea is a shrub or small tree bearing

exstipulate, simple, alternate leaves. The five-merous

flowers are arranged in panicules, and each possesses a

superior ovary that ripens into a capsule (Bailey, 1900;

Engler, 1928).

Most systematists agree that Cuttsia belongs in either

the subfamily Escallonioideae of the Saxifragaceae (Engler,

1890, 1928; Schulze-Menz, 1964; Thorne, 1976, 1983) or the

Escalloniaceae (Airy Shaw in Willis, 1973; Dahlgren, 1975,

1980, 1983; Takhtajan, 1966, 1980). Cronquist (1968,

1981), however, placed this genus in his Grossulariaceae.


Observations

Cuttsia possesses simple, elliptic to ovate, serrate

leaves. Venation is semicraspedodromous with a prominent









midvein and conspicuous secondary veins whose branches

extend near the leaf margin and arch distally to join with

superadjacent secondary or tertiary veins (Fig. 58). Areole

development is incomplete. Veinlets may be straight,

curved, or branched one to three times (Fig. 59). Vein

endings are composed of two to five helically thickened

tracheids that are surrounded by large-diameter parenchyma

cells of the bundle sheath. These tracheids are usually

elongate and possess very small protuberances whose position

corresponds to the interface between two bundle sheath cells

(Fig. 59).

The nodal pattern is trilacunar, three-trace, and three

collateral bundles enter a petiole (Fig. 60). Near the base

of a petiole a very small accessory vascular bundle branches

from each of the lateral bundles near the adaxial surface of

the petiole (Fig. 60). Distally from the point of diver-

gence of these accessory bundles, the three main petiolar

bundles fuse laterally to form a large horseshoe-shaped

vascular bundle in the center of the petiole (Fig. 60). Two

bundles may split from the adaxial side of this large cen-

tral bundle (Fig. 60) or, in some petioles, the ends of the

large central bundle may invaginate or become inrolled. In

some petioles these inrolled ends may fuse to form a large,

medullated concentric bundle with the xylem internal to the

phloem. Distally each of the accessory bundles near the

adaxial surface of a petiole splits to form two additional

accessory bundles (Fig. 60).








Leaves of Cuttsia are dorsiventral with a well-

differentiated biseriate palisade layer and a lacunose

spongy mesophyll layer (Fig. 61). The palisade cells

adjacent to the spongy mesophyll are widely spaced and

exhibit various shapes and sizes compared to the columnar

and closely appressed cells of the remainder of the palisade

layer (Fig. 61). The spongy mesophyll is approximately the

same thickness as the palisade layer and is composed of

cells of various shapes and sizes and relatively large

intercellular spaces. Crystal sand occurs sporadically in

the larger cells of the spongy mesophyll (Fig. 62). In

addition small clusters of yellowish cells are visible

throughout the mesophyll of cleared leaves (Fig. 59).

The midvein of Cuttsia leaves may be arc-shaped,

horseshoe-shaped with either collateral bundles or inrolled

ends at the top of the horseshoe, or concentric and

medullated (Fig. 63). Secondary growth is well-developed in

the midvein and larger bundles (secondary veins). A large

bundle sheath of thin-walled parenchyma cells surrounds each

vascular bundle of a leaf (Fig. 61). Abaxial and adaxial

bundle sheath extensions are associated with most bundles

except for the very small veins. These bundle sheath

extensions are composed of thick-walled parenchyma and

collenchyma cells.

The adaxial epidermis is biseriate, whereas the abaxial

epidermis is uniseriate (Fig. 61). In transaction the cells

of the abaxial epidermis and the outermost cells of the

adaxial epidermis are rectangular to oval in outline. The








subjacent cells of the adaxial epidermis are square, round,

oval, or rectangular (Fig. 61). In surface view the cells

of the abaxial epidermis and the outermost cells of the

adaxial epidermis are variously shaped and possess curved

and sinuous anticlinal walls. The cuticle overlying both

epidermides is very thin (<5 um). Unicellular, elongate,

bulbous-based, thick-walled trichomes with tapered ends

generally are sparse on abaxial leaf surfaces, but are

common along the large veins.

Numerous stomata occur mostly in the abaxial epidermis,

but also occur in the adaxial epidermis in association with

hydathodes. The stomatal apparatus is anomocytic. In sur-

face view individual guard cells are reniform, and guard-

cell pairs are elliptic in outline (Fig. 64). Guard-cell

pairs average 29 um in length and 21.3 um in width (length/

width ratio 1.36). In transaction the guard cells are

galeate in outline, and each cell bears a small cuticular

horn that represents the outer ledge overarching the stoma.

The apex and marginal teeth of a leaf of Cuttsia con-

tain hydathodes. A prominent vein flares as it enters each

marginal tooth (Fig. 65). In leaf clearings, a callosity

composed of thick-walled cells is visible at the apex of the

rounded marginal serrations. These thick-walled cells stain

more darkly than other cells of a tooth (Fig. 65).

The wood of C. viburnea lacks growth rings (Fig. 66)

and is fine-textured with numerous pores (range 10 -75/mm2

x= 37) that possess moderately small diameters (range 39-88

um, x= 64) and relatively thin radial walls (range 1.6-6.3








um, x= 3.5). Pores are predominantly solitary (87%), al-

though radial multiples of two pores (1%) and clusters of

two to four pores (12%) mostly due to overlapping end walls

of contiguous vessel elements do occur. The pores primarily

are angular in outline, however some may appear circular

because their corners are often rounded (Fig. 66). The

vessel elements are long (range 817 to 2367 um, x= 1368) and

possess steeply inclined oblique end walls. End-wall angles

range from 6-300 (x= 15). Peforation plates are exclusively

scalariform and possess 32-104 bars per plate (x= 57) (Fig.

67). Occasionally two scalariform perforation plates occur

per oblique vessel element end wall. Scalariform perfora-

tion plate bars are thin and may be forked or branched.

Perforations are bordered at the ends. Transitional, oppo-

site to alternate intervascular pitting is confined to over-

lapping end walls, and the pits often intergrade with the

scalariform perforation plates (Fig. 67). Pits are small in

diameter and range from 3.2-5.8 um (x= 4.6).

Tracheids have circular bordered pits with oval aper-

tures that may be included within or extend beyond the

margins of the pit border (Fig. 67). The diameter of these

pits is similar to that of the intervascular pits. These

cells are very long (range 1517-3267 um, x= 2396 um).

Tracheid wall thickness varies from 3.7 to 13.7 um (x= 7.5

um). Fine spiral thickenings are present in most of these

tracheary elements (Fig. 67).

Axial parenchyma is sparse and mostly apotracheal dif-

fuse or diffuse-in-aggregates with short tangential bands









of two to four cells (Fig. 66). Rarely xylem parenchyma is

paratracheal scanty. Vessel to axial parenchyma pitting is

transitional, opposite or alternate. No ergastic substances

are noted in these cells.

Although the xylem ray system is predominantly composed

of homocellular, uniseriate rays of upright cells and heter-

ocellular, multiseriate rays (Fig. 68), a few homocellular,

biseriate rays of upright cells are present in each speci-

men. Ray height ranges from 2-27 cells (1.33-3.23 mm) for

uniseriate rays, 4-30 cells (.65-3.92 mm) for biseriate

rays, and 24-251 cells (1.40-11.37 mm) for multiseriate

rays. Biseriate rays are 10-13 um wide, and multiseriate

rays mostly are 3-9 cells (34-163 um) wide. One specimen

(FPAw 18202) had rays up to 20 cells (650 um) wide. No

ergastic substances are noted in these cells. Sheath cells

completely surround the multiseriate rays (Fig. 68), and

perforated ray cells with scalariform or reticulate perfora-

tion plates are commonly found in the uniseriate tails of

multiseriate rays (Fig. 69). Vessel to ray parenchyma pit-

ting is similar to pitting between vessels and axial paren-

chyma and is scalariform, transitional, opposite, or alter-

nate. Multiseriate rays often are split by tracheids and/or

vessels, and occasionally multiseriate rays are fused end-

to-end.































Figure 58. Leaf of Cuttsia viburnea. Xl/2. Note marginal
serrations and semicraspedodromous venation.

Figure 59. Vein ending of C. viburnea X175. Note small
clusters of cells in the mesophyll.

Figure 60. Transverse sections of a node (a) and proximal
(b), median (c) and distal (d) sections of a petiole of C.
viburnea. X13.


Details: cc, cluster of cells; t, tracheids.


I ~_ ~_




















58


"1


60


6


59























Figure 61. Transverse section of a leaf of Cuttsia
viburnea. X175. Note biseriate adaxial epidermis.

Figure 62. Crystal sand (arrows) in the spongy mesophyll
layer of a leaf of C. viburnea. X700.

Figure 63. Transverse section of a midvein of a leaf of C.
viburnea. Xll0. Note the constricted nature of the adaxial
bundle sheath extension.

Figure 64. Paradermal section of the abaxial epidermis of a
leaf of C. viburnea. X700. Note anomocytic stomatal
apparatus.

Figure 65. Marginal serration of a leaf of C. viburnea.
X110. Note the prominent flaring of vein and the apical
callosity.


Details: ab, abaxial epidermis; ad, adaxial epidermis; b,
bundle sheath; be, abaxial bundle sheath extension; be',
adaxial bundle sheath extension; c, cuticle; ca, callosi-
ty; gc, guard cell; pl, palisade layer; sl, spongy meso-
phyll layer ; st, stoma; vb, vascular bundle; v, vein.





I

























Figure 66. Transverse section of the secondary xylem of
Cuttsia viburnea. X110. Note solitary, angular pores and
diffuse and diffuse-in-aggregates axial parenchyma.

Figure 67. Radial section of the secondary xylem of C.
viburnea. X437. Note fine spiral thickenings (arrow).

Figure 68. Tangential section of the secondary xylem of C.
viburnea. X110. Note sheath cells.

Figure 69. Radial section of the secondary xylem of C.
viburnea. X175. Note perforated ray cell with a scalari-
form perforation plate. X175.


Details: ap, axial parenchyma; p, pore; pc, perforated
ray cell; pi, pits; pp, perforation plate; r, ray; sc,
sheath cell; t, tracheid.







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