Wentia 7 (1-116)

Pollen morphology of the

euphorbiaceae with special reference

to taxonomy

W. Punt

(Botanical Museum and Herbarium, Utrecht)

(received December 28th, 1961)

CONTENTS

Chapter I General Introduction 2

a. Introduction 2 b. Acknowledgements 2

Chapter II History 2

a. Pollen morphology 2 b. Euphorbiaceae 4

Chapter III Material 5

Chapter IV Methods 6

a. Flowers 6

b. Pollen preparations 7

c. Preservation of pollen grains 7 d. Microscopes 8

e. Punched cards 8

f. Drawings 9

Chapter V Some nomenclaturalremarks 9

Chapter VI Pollen morphology 10

Chapter VII Glossary 15

Chapter VIII Results 18

A. Pollen grains of the Euphorbiaceae 18

B. Discussion of the results 20

a. Phyllanthoideae 20

Antidesma configuration 20 Amanoa configuration 32

Phyllanthus nutans configuration 37 Breynia configuration 38

Aristogeitonia configuration 40

b. Crotonoideae 47

Croton configuration 47 Cnesmosa configuration 57 Dysopsis configuration 60 Plukenetia configuration 60 Chiropetalum configuration 65

Cephalomappa configuration 68 Sumbavia configuration 69 Bernardia configuration 73 Mallotus configuration 77 Claoxylon configuration 90

Cladogynos configuration 93 Hippomane configuration 95

Summary 106

References 107

Index 110 CHAPTER I

GENERAL INTRODUCTION

a. Introduction

Many investigators have stated (e.g. Lindau 1895, Wodehouse

1935, Erdtman 1952), that pollen morphology can be of great importance for plant taxonomy, while it was also known that in of Erdtman Euphorbiaceae several types pollen grains exist (e.g. 1952). On the suggestion of Professor Lanjouw, who himself has worked the on the Euphorbiaceae of Surinam, the author has investigated pollen

of that From grains of this family area. the result it was apparent that in Surinam different the Euphorbiaceae many pollen types could be In the work the extended distinguished. present study was therefore the in the from which to all genera Euphorbiaceae, one or more species Besides of have been examined. a description the pollen grains examined a drawing of most of the pollen types is given. The pollen with the morphologic groupings found have been compared systems ofseveral authors (Bentham and Hooker 1880, Pax and K. Hoffmann have 1931, etc.). The taxonomic conclusions, however, can only a provisional character. Future investigators of the Euphorbiaceae will have to check the taxonomic notes and comments.

b. Acknowledgements

The investigations have been carried out at the “Botanisch Museum en Herbarium”, Utrecht. The writer is greatly indebted to the

director, Professor Dr. J. Lanjouw, for giving him the opportunity to

his and for and carry out the investigations at institute his help in this The author is much indebted guidance preparing paper. very to Professor Dr. F. P. Jonker who advised him in the special problems of He the “Ministerie pollen morphology. very gratefully acknowledges van Onderwijs, Kunsten en Wetenschappen” for sponsoring the The author wishes his sincere thanks the present study. to express to directors of the herbaria at Brussels, Leiden, Kew and Paris for the hospitality and help during his residence in these places. He is also the which covered the of very grateful to “Miquelfonds” expenses his stay in London, Paris and Brussels where so much valuablematerial could be examined.

CHAPTER II

HISTORY

a. Pollen morphology

The study of pollen morphology started in 1675, when Malpighi in observed, that various types ofpollen grains are to be found different He variations of colour and Grew plants. especially saw shape. (1682) of differencein He was already aware a structure, too. distinguished POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 3 smooth and spiny pollen grains. In the next two centuries quite a number of botanists enriched our knowledge of pollen morphology.;

In 1834 a synopsis of the literature on the subject was published by v. Mohl, which greatly contributed to a better understanding of pollen morphology. He studied representatives of most of the plant families and classification of their forms, Mohl gave a descriptive v. recognized that the apertures of the pollen grains are the most features. Some later Fritzsche important morphological years published his principal work on pollen grains (Ueber den Pollen,

From the careful 1837). descriptions it is clear that, besides a study of the of the shape and apertures a pollen grain, structure was accu- rately analysed. His drawing and description of Jatropha panduraefolia The gives an excellent idea of the pollen grain. description even very accurately reproduces the construction of the croton-pattern (see PI. I, E4 and PI. VIII, 1).

In the period after v. Mohl and Fritzsche we come across publications with drawings of pollen grains as additions to analytic; drawings ofplants (e.g. in Martius, Flora Brasiliensis). Most botanists, however, added but little to pollen morphology. C. A. H. Fischer in was the first scientist to give, 1890, a comprehensive comparative study of the data then available. From the study of 2200 species in 158 families he able the conclusions: was to draw, e.g. following

Pollen similar. 1: grains of related species are generally

2: Some families have more than a single basic form. 3: Sometimes unrelated plants have similar pollen grains.

In 1883 Radlkofer made use of pollen morphology to obtain a better classification of the Acanthaceae. It \yas done more profoundly by Lindau (1895) in “Die natiirlichen Pfianzenfamilien” by Engler and

Prantl when he stated: “Es ist deshalb nur consequent, wenn auf die Pollenbeschaffenheit die Einteilung der Acanthaceae gegriindet wird, wie dies bereits von Radlkofer angcdeutet wurde und im folgenden werden soil”. It is obvious with ganz streng durchgefiihrt that, regard to some families, pollen morpholqgy had become a wellknown and end of indispensable part of taxonomy at the the 19th century. In in fact, a renewed general interest pollen morphology emerged, of the of not from the side botany, but from side geology. It was the geologist v. Post who, in 1919, for the first time published a modern pollen analytic diagram; the primitive pollen analysis had resulted in method in the a refined quaternary geology. However, composition of of the a pollen diagram requires a sound knowledge morphology of pollen grains. Originally a primary acquaintance of the pollen grains of trees and anemophilous plants was considered to be sufficient, but more and more the necessity of a wider knowledge of pollen types became evident. Consequently the number of investigators who made researches into the of taxonomic pollen morphology special groups increased.

in Potoni£ in 1934 and Wodehouse 1935 published works on pollen morphology that formed the basis of our modern terminology. 4 w. PUNT

of well Potonie as well as Wodehouse needed a system defined terms for the details of description of pollen grains. The construction and a well known pollen grain were, however, not enough to be arranged in convenient a system. Nevertheless, many terms of these investigators still in sometimes the are use, although circumscription of the terms

is more or less altered.

In 1950 Faegri and Iversen, and Iversen and Troels-Smith

published a system on the morphology of pollen grains. Their ter-

minology excelled in exactitude and simplicity. The well-defined terms

determine made it quite possible to pollen grains which occur in their determination-key of European pollen types.

At the same time Erdtman also worked at a system of pollen

terminology. He published several papers on this subject, but his main work and (Pollen morphology plant taxonomy, Angiosperms) appeared in In this book Erdtman extended of 1952. proposed an system In the pollen terminology. many respects, however, terminology seems too complicated to be of practical use. Only pollen morphologists able all the with a large experience are to identify terms mentioned in the glossary. Moreover, the descriptions of terms are not always as exact as they should be. What, for instance, is the exact boundary

between brevicolpate and brevissimicolpate or foramen and fora-

his book is of minoid? Nevertheless, a source valuable data providing primary information of the pollen types of all the families in the Angiosperms. b. Euphorbiaceae

This It family is one of the largest in the Angiosperms. is a difficult of the different thatit is one on account many species, so not surprising, of the whole that only a few botanists possessed a general knowledge family. Since the present report is mainly a pollen morphologic work, the following lines will only briefly comment on the principal authors on Euphorbiaceae.

In the 19th century A. de Jussieu, J. Mueller of Argau and

H. Baillon published important papers on the Euphorbiaceae. In the Journal of the Linnean Society (Botany) of 1880 Bentham reviewed the work of Baillon and Mueller Arg. In the Bentham same paper

extensive notes on his own gave system. From 1910-1924 Pax (partly assisted by Kathe Hoffmann) in monographed most of the genera Euphorbiaceae in Engler’s “Das Pfianzenreich”. In the second edition of Engler and Prantl, Die

Natiirlichen Pfianzenfamilien, Band 19c (1931), a revised synopsis is In the this of 1931 of the Euphorbiaceae given. present paper synopsis been has used as the basic classification of the family. After Pax and K. Hoffmann only incidental remarks have been

made on the system of the Euphorbiaceae. Most of them were given in

floras of certain areas Leandri, Flora of papers concerning (e.g. Madagascar; Gagnepain, Flora of Indo-Chine; Leonard, Flora of have been made Croizat Congo). Important improvements by on POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 5 several Schultes discussed the Hevea and its genera. amply genus allies. A very important work is Webster’s publication on Phyllanthus. In his monographic study “The West Indian species of Phyllanthus"

he used pollen morphology as one of the main characters to divide the into and sections. genus Phyllanthus subgenera

CHAPTER III

MATERIAL

material from the herbaria Herbarium obtained following was used in the study;

London (BM): British Museum (Natural History). Bruxelles (BR); Jardin Botanique de 1’Etat. Bruxelles (BRLU): Herbier d’Afrique de l’Universit6 de Bruxelles. Kew (K); The Herbarium, Royal Botanic Gardens. Leiden (L): Rijksherbarium. Paris (P): Museum National d’Histoire Naturelle Laboratoire de Phanerogamic. Utrecht (U): Botanical Museum and Herbarium. Wageningen (WAG): Laboratory for Plant Taxonomy and Plant Geography.

Generally the use of type-material has been avoided. Only in those where other available cases, no specimens were while flowers has for were present, type-material been used pollen investigation.

The classification of the Euphorbiaceae as given by Pax and K. Hoffmann in Engler and Prantl, Die natiirlichen Pflanzenfamilien ed. 2, Band 19c (1931), was the principal system used for the choice of Besides this attention has been the genera. system paid to new genera after listed in published 1931 and the Index Kewensis. As far as all known of the examined. possible genera Euphorbiaceae were In a

number of genera it was, for various reasons, impossible to study the fall in the pollen grains. They following groups:

1. Male flowers unknown.

Croizatia Steyermark

Lasiochlamys Pax et K. Hoffmann Paradrypetes Kuhlman Phyllanoa Croizat

The material did male 2. studied not contain flowers, or only a

few, or unripe ones.

Claoxylopsis Leandri Calicopeplus Planghon

Cometia Thouars ex Baillon

Corythea Watson Ditta Grisebach

Keyodendron Leandri Mettenia Grisebach

Monadenium Pax 6 w. PUNT

Neomphalea Pax et K. Hoffmann Neotrigonostemon Pax et K. Hoffmann Ramelia Baillon Riseleya Hemsley Syndyophyll um Schumacher et Lauterbach Sphyranthera Hooker, J. D. Thelypetalum Gagnepain

3. Genera of which no material has been seen.

Acalyphopsis Pax et K. Hoffmann Annesijoa Pax et K. Hoffmann

Chlamydojatropha Pax et K. Hoffmann

Clarorivinia Pax et K. Hoffmann

Gitaria Pax et K. Hoffmann Senefelderopsis Steyermark

On of the number of and the author account large genera species has found be of the it impossible to always sure accuracy (both taxonomic and ofthe used in the nomenclatural) names present paper.

Future monographic studies will perhaps prove some names to be incorrect. With all the descriptions of pollen grains, however, the

and the collector’s name and number the herbarium, where specimen In is preserved, are given. those cases when the name has to be

be corrected the description of the pollen grain can thus always

placed under the right name.

In the Rijksherbarium at Leiden a large collection of plants of

D’Alleizette is present. These plants, however, have not been collected by D’Alleizette himself. In the herbarium at Paris D’Alleizette obtained duplicates from several collectors. These duplicates were sent the to Rijksherbarium without mention of the names and collectioning collectors. As it lies the of this numbers of the original beyond scope work search for the of the of to names original collectors, the name

D’Alleizette has been maintained in the present work.

CHAPTER IV

METHODS

Flowers a.

From each least and when genus at one species possible two species were examined.

From those that be devided into two were genera can or more sections, species chosen from different sections.

Usually the male inflorescenses of the Euphorbiaceae have many flowers, so that,

it flowers dissected. generally speaking, no important loss occurs one or two are

- Only those flowers of the Euphorbiaceae are useful that have just opened. When

the flowers the has not that it is to are younger pollen yet ripened, so impossible

give an accurate description of shape and structure of the pollen grains. It is far better anthers than and to use old, outpollinated young undoubtedly unripe ones. old which, In the corners of their thecas the anthers always have some pollen grains

by a special micro-method described below, can be isolated. POLLEN MORPHOLOGY OF THE EUPHORBIACEAB 7

b. Pollen prepararions

For the study of the morphology of pollen grains it is desirable that cytoplasma dissolved. and intine are The microscopic image becomes obscure and the important cxine remains indistinct if intine and cytoplasma are not dissolved. For that reason the lactic-acid method and other Wodehouse’s methylene-green method, any method, which does not completely dissolve intine and cytoplasma are considered less suitable.

The treatment of the pollen grains with the acetolysis-method of Erdtman (1943)

the best inside the exine is produces results. Everything dissolved, while, moreover, a colouring of the exine takes place. This method, described by Erdtman in 1943 and for herbarium in 1952 material, has, its original form, a great disadvantage.

Too much material is required to obtain a usable preparation. In order to reduce this micro-method has been which leaves disadvantage a (see below) applied, the method such but less material. If as untouched, requires necessary even only one anther is sufficient.

Micro-method

The micro-method is a perfection of the method described by Willrath in a publication of Potonie (1934).

A flower is boiled in water till it is free of air. Under a preparing-microscope

one anther (or more if the material allows) is dissected and laid in the pit of a hollow slide. Some drops of acetolysis mixture (9 parts anhydric acetic acid : 1 part

H2SO4 are till the been filled with mixture. cone.) dropped on the anther pit has the

Now the slide is placed on a heating-apparatus as shown in Fig. 1. The end of the

is heated Bunsenburner. The flame not be too heating-apparatus by a should high,

Fig. 1

but not too low either. The slide furthermore has to be removed so far from the

flame that the mixture cannot take fire. A part of the mixture will evaporate.

When the slide has become almost dry some more drops are added. This is repeated 3 4 times till the mixture is dark the or remaining turning brown. When preparation

once more is nearly “dry”, it is quickly cooled down by placing the slide on a stone

or iron surface. Under the dissecting microscope the pollen grains are to be seen

as brown globules. With anthers which have a solid skin, that cannot easily be

dissolved, it is desirable, while heating, to prick this skin in places with a needle

to make the acetolyse mixture penetrate deeply enough into the anther.

c. Preservation of pollen grains

For the preservation of grains the paraffin-comprising method has been used.

A small drop of glycerin (diam. 1 mm.) is laid on a slide. With a brush moisted in

glycerin the pollen grains are wiped off the slide or fished out of the liquid. In 8 w. PUNT

the drop of glycerin the pollen grains come off the brush more or less easily. This is repeated till at least 10 grains are present in the glycerin drop.

Now a little piece of glycerin-gelatin is added. The gelatin is melted and the mixed with it. To the from grains are prevent pollen grains expandingabnormally the whole should not be heated too much. It is of the utmost importance that the grains can be studied from all sides, so that care should be taken that the cover- glass does not flatten the grains. Therefore a granule ofclay (no synthetic material) is laid next to the glycerin drop. The cover-glass is now supported by the clay when and cannot be placed on the preparation the pollen grains compressed. By lightly pressing the cover-glass the thickness of the preparation can be regulated. By running melted paraffin under the cover-glass the grains are isolated from the air.

Webster the of the (1956) rejects method sealing up by paraffin on ground of the durable. In preparations not Utrecht, however, preparations ten years old are still in excellent condition. It is, however, essential that the layer of paraffin should not be too thin and the drop of glycerin should not approach the edge of the cover-glass (Erdtman and Praolowski 1959). made the micro-method have the that Preparations by disadvantage some acid will with the This the colour fade after enter pollen grains. may cause to some time. After three form and still For years, however, structure were unchanged. that reason the macro-method ofErdtman is always preferable to the micro-method, but the latter has the that little material is that advantage very sufficient, so any

sacrifice of herbarium-material be In the of rigorous may prevented. case flowers with anthers it is even that of a stamen suffices large possible part (Campanula, Lilium).

In describing pollen grains it is of great importance that the method used for preparation should be indicated, since the size of the pollen grain varies with it.

Though the expansion of a certain pollen grain is constant in either method, only relative value can be attached to the indication of the size of that particular pollen grain. Only with regard to pollen grains that have been treated in precisely the the retain their the size is same way grain measures value. Moreover, influenced of ofthe When is the of by the grade ripeness pollen. a pollen grain on verge maturing, form and be while the size has structure may already fully developed, not yet reached its maximum. It is, therefore, again emphasized that all absolute numbers which mentioned in the have relative value. For this are descriptions a reason any calculation of sizes has been The accurate average relinquished. figures give an impression of the size in these special circumstances and allow a mutual comparison of the examined pollen grains.

The proportionate numbers, however, are more dependable. Proportions remain the in either Some numbers Polar Area same method. proportionate are, e.g.. Index (=P.A.I.) and Polar axis: Equatorial axis (= P:E) (see Pollen Morphology p. 12).

d. Microscopes

The pollen grains were studied with a Bausch and Lomb binocular (objective

97 x, oculair 10 X ), and an Olympus phase contrast microscope was used. The of this useful in the employment microscope was found very detecting configuration of elements. of also structure Most the structure patterns are visible with the ordinary light-microscope, but, especially in the case of small structure elements, not without

The contrast clear difficulty. phase microscope immediately gives a image of the structure.

e. Punched cards

The study of large quantities of material requires special methods of compiling the obtained. A card-index is when there knowledge simple inadequate are many be the number of characters genera to mutually compared; great hampers any efficient A solution of this found in the of arrangement. problem was use punched cards. Punched card systems were made for the pollenmorphologic as well as for the taxonomic characters. Thus botanical could be any particular object classified in The of within those two independent systems. groups genera systems

now so correlations are mutually comparable that it became possible to recognize POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 9

of characters, which, without the punched cards, would have been found at the cost of much time and labour or not at all.

A further advantage is that the investigator is compelled to look over the same characters Even the absence of character be of continually. a special may importance and finds in this expression system. A be that much reliance is the characters disadvantage may too placed upon noted. Often characters that indicated in the are same way are not mutually If this coalescence take various forms. comparable. e.g. stamens are connate, can There be who this Nevertheless may investigators, are inclined to distrust system. the of cards and other mechanic should be taken use punched systems undoubtedly into consideration, especially when studying larger taxa. Surveying and work- the numbers of characters in reasonable time ing up continually increasing a is becoming more and more difficult. Loss of time, chance of errors and the risk of being incomplete are apt to compel the taxonomist to utilize some form of mechanic

Who revise the whole Solanum taxonomy. would, at present, venture to genus or

Euphorbia? Only through a perfection and especially through an acceleration of

will as a our methods the larger taxa yet have chance of being monographically worked on. f. Drawings

The have been drawn in such that in pollen grains a manner one drawing as

characters be the time. Each therefore many as possible are to seen at same drawing is midway between a scheme and a photographical reproduction. The pollen grains have been drawn without a camera lucida or other drawing instruments.

Drawing has the advantage that the most important characters can be indicated from distinctly, so that the grains are easier to distinguish others. A disadvantage is the subjective image which the drawing is apt to give.

The other possibility of reproduction is making use of photography. For the method following reasons this has not been applied;

most at least 4 of to obtain 1. In cases photographs perfect quality are required

a distinct picture of the grain.

In the structures of the be 2. a photograph pollen grains can never pursued

distinctly, because the photographic image will only be sharp for a certain optical section.

3. Deeper lying layers debase the photographic image and cause an insufficient sharpness of the essential characters.

The plates have been drawn to scale. Each picture is 1000 X enlarged, except some of the large pollen grains (e.g. Manihot and Croton matourensis),,, which are _____ less where the is 1500 the is enlarged. In those cases enlargement not X scale given in the text to the plates.

CHAPTER V

SOME NOMENCLATURAL REMARKS

Bischofia Blume

Blume dedicated this Bischoff he in his Although genus to spelled, “Bijdragen” (1826), the name with a single f. Obviously he latinised Bischoff to Bischofius. For this the of the should be written in the reason name genus original spelling.

Briedelia Willdenow

In his “Species Plantarum” (4:978. 1805) Willdenow deliberately spelled the follows genus with i e. He commented as on the choice of the name: “Genus hoc _ a Cluytia et Rhamno abunde diversum in honorem Clariss. S. E. Briedel nominavi.”

Although the name of the botanist in question is spelled Bridel it is not clearly demonstrated that the author made an unintentional error. Under the rules of the international code the should be written in the genus original spelling. 10 w. PUNT

Cnesmosa Blume

In his Blume this Cnesmosa. In the Flora “Bijdragen” (1825) spelled genus as van Java, Praefatio in adnotation, he changed the name, probably for grammatical “ in reasons, Cenesmon. This is not allowed under the rules of nomenclature. The original spelling should be maintained.

Koilodepas Hasskarl

Koilodepas was first published in 1855 in the Greek version (Versl. Med. Akad. Amsterdam 4: Two later Wetenschappen 139). years the name was altered in Coelodepas (Flora 40; 531. 1857). As Croizat (1942b) and Airy-Shaw (1960) have stated, the validity of the spelling Koilodepas is unquestionable.

Omalanthus A. de Jussieu

The first ofthis in A. “De spelling genus appeared deJussieu’s Euphorbiacearum” in In his H. G. L. Reichenbach altered the in 1824. “Conspectus” (1828) name

Homalanthus. Of the first has be maintained. course spelling to Carumbium is a syn- of Reinwardt this nudum in onym Omalanthus. published name as a nomen Oken’s Isis 1823. So Omalanthus first is the name published and therefore valid.

Romanoa Trevisan

In A. the Anabaena. De had 1824 de Jussieu published genus Bory, however,

the Anabaina in that the given name to a new algae genus (Cyanophyta) 1821, so of A. is In 1918 Pax K. Hoffmann the name de Jussieu a homonym. et gave substitute Anabaenella name to this taxon. They did not know, however, that an older name was available. In 1848 Trevisan had substituted Anabaena A. de Jussieu

Romanoa Coccotale If the is held from by (Alghe p. 99). genus separate Plukenetia,

Romanoa is the first correct name for Anabaena A. de Jussieu.

CHAPTER VI

POLLEN MORPHOLOGY

In describing pollen grains the number of terms employed should of Faegri be as small as possible. This was the starting point and

in Iversen 1950. One of the arguments they advanced was the

difficulty of giving an analytic description of a pollen grain in exact The their terms. system, however, that resulted from attempt at

PLATE I.

A. 1. pori; 2. colpi; 3. prolate pollen grain; 4. oblate pollen grain; P = Polar axis;

E = Equatorial axis.

B. polar view; 1. triangular; 2. three lobed; 3. circular; 4. convex triangular;

S = smallest distance between two colpi ends; G = greatest breadth; S:G = Polar

Area Index.

C. 1. and and with membrana 3. porus colpus nudate; 2. p. c. a granulata; p.

and with 4. and with b c. an operculum; p. c. a margo (thickening a or thinning ofthe 4c. and 5a. with 5b ekt.); costae pori costae colpi; porus a vestibulum; and c.

composite aperture with an atrium.

D. 1. colpus transversalis; 2. circular colp. transv.; 3. equatorial colp. transv.;

= meridional axis of the axis of the m cop. transv.; e. equatorial colp. transv.;

o = os; 4. costa transversalis; 5. costa circularis; 6. costa equatorialis.

E. 1. tectum; 2. tectum perforatum; 3. reticulum; 4. croton-pattern.

1. F. psilate; 2. scabrate; 3. verrucate; 4. gemmate; 5. clavate; 6. baculate; 7. echinate; 8. pila. 11 POLLEN MORPHOLOGY OF THE EUPHORBIACEAE

PLATE I. 12 W. PUNT

and simplicity was inadequate, amplification was necessary. Especially when the of material be described is considerable amount to many The number of characters difficulties are liable to arise. of a pollen

smalland often in transitional grain is comparatively they appear many forms. and Yet a precise exact definition of characters is desirable. Erdtman, who, in his study of the Angiosperms (1952), met with these difficulties, therefore enlarged the terminology considerably. He

each which could tried to nominate every transitional form, nuance, be achieved only at the cost of exactitude and convenient arrangement.

Nevertheless many pollen morphologists will feel highly attracted towards his method.

For the use of pollen morphology as an additional character in is The characters taxonomy this system too complicated. more obvious will suffice. For that reason a compromise seems to be the right course the far for description of diverse pollen grains. Without going as as

Erdtman the present author has attempted to use a terminology as without loss simple as was possible of exactitude and completeness.

Pollen grains are composed of three layers. The central part is the cytoplasma. The middle layer is the intine; the outer layer the exine.

The exine of pollen grains consists of a particularly resistant substance character: is of a lipoid sporopollenin. Sporopollenin even more resistant to the attack by micro-organisms than cutin. The exine substance is also highly resistant to all sorts of chemicals; it can not, or only slowly, be attacked fluid concentrated fluoric by KOH, H2SO4 or even acid (HF).

The exine which can be devided in two layers, the endexine and the of the data for ektexine, supplies most necessary pollen description. data fall into three These groups:

1. Shape 2. Apertures 3. Structure

1. Shape

If a pollen grain is not spheroidal we can distinguish two axis: a. Polar axis (P) (PI. I, A3 and A4) b. Equatorial axis (E) (PI. I, A3 and A4)

In equatorial view pollen grains show a shape which will be P: E. this determined easily now by calculating the According to relation we distinguish the following classes (Erdtman 1952):

P E : > 2 : perprolate

1,33-2 : prolate (PI. I, A3) 1,14-1,33: subprolate 1 —1,14: prolate spheroidal

1 : spheroidal

1 -0,88: oblate spheroidal 0,88-0,75: suboblate 0,75-0,50: oblate (PI. I, A4)

< 0,50: peroblate POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 13

In the of polar view circumference a pollen grain can be:

1. triangular (PI. I, Bl)

2. convex triangular (PI. I, B4) 3. circular (PI. I, B3) 4. three lobed (PI. I, B2)

2. Apertures

In the system of Iversen and Troels-Smith the principal classifi-

cation is made according to the occurence of apertures: pori (PL I, Al), colpi (PI. I, A2) and colpi transversales (PI. I, Dl, 2, 3) (in composite

apertures only). Real and real in the pori colpi are formed by thinnings ektexine.

A colpus transversalis, on the other hand, by a thinning in the endexine. For that of the endexine and the ektexine reason apertures have to be described independently of each other.

Pori can be distinguished from colpi by calculating the length: breadth the is breadth. If length: < 2 aperture a porus although the is not circle. If breadth 2 the shape necessarily a pure length: > aperture is a colpus. The endexine below the edges of colpi or pori

be thickened. These called costae and may thickenings are colpi costae pori (PI. I, C4c). The colpus transversalis (PI. I, D) is an easily recognisable character. It the Yet this is a thinning of endexine. aperture has been inaccurately described Faegri and Iversen confuse by many investigators. (1950) this with real when the transversalis has aperture a porus colpus the

shape of a circle. Consequently, when using their key for the deter-

mination of European pollen types, it is sometimes difficult to decide if a “porus longitudinal elongated” or a “transversal furrow” is

“ present. Erdtman calls colpi + colpi transversales composite apertures”. the transversalis he the For term colpus introduced new term os

in (Pi- ora). If this term is used that sense the name will have to be be maintained rejected as being a synonym. It may, however, for that the part of colpus transversalis that crosses the colpus (PL I, D3).

Colpi transversales stand perpendicular on the colpi. Usually they are fuse boat-shaped. Sometimes they together into one single aperture

along the equator of the pollen grain (colpus transversalis equatorialis), but it is also possible that the colpus transversalis becomes isodiametric (colpus transversalis circularis PL I, D2). The medial dimension of the the Pleiostemon colpus transversalis is rarely larger than equatorial one ( transversales type, p. 30). Edges of colpi can also have thickenings; transversalis according to the shape of the colpus they are called: costae circulares, costae transversales and costae equatoriales (PI. I, D4, 5, 6).

To the of the transversalis in exact express proportions colpus figures, the quotient m: e is added to the description of this character. In meridional and axis of the this formula m is the axis e the equatorial colpus transversalis (PI. I, Dl).

Iversen and Troels-Smith (1950) introduced the term Polar Area

Index (P.A.I. ). The P.A.I. is the ratio between the greatest distance of of the the the ends two colpi and greatest breadth of pollen grain 14 W. PUNT usually the Equatorial axis. This character is of great value for the description of pollen grains.

3. Structure

The ektexine furnishes characters of great diagnostic importance. with The description of these characters meets, however, considerable

difficulties, so that it is necessary to use a system as simple as possible

and highly desirable to avoid confusing terms (e.g. sculpture, see below). The ektexine is composed of structure elements. Different forms and

arrangements of these elements cause several structure types to occur. The elements most common structure occuring on the endexine are pila (PI. I, F8). Each pilum consists of a swollen apex' (caput) and a basal cylindrical part (collum; homologous columella). Pila are strictly found the endexine. ordinate inordinate. on They may occur or Ordinate form arranged pila can regular figures (e.g. reticulum PI. I, E3) or stand in rows striae). Frequently capita of pila are connate or (e.g.u x fused. If the fusion is only laterally, and less of the surface is covered by the capita, we speak of tegillate pollen grains. Pollen grains are fused 80 the surface tectate when the capita cover % or more of

(PI. I, El). In that case the pila form a second membrane outside the endexine. If the tectum is not completely closed (fusion of the capita

than 80 less than 100 the membrane is more % and %) perforate a tectum perforatum (PI. I, E2).

On the top of the tectum we distinguish structure elements of different shape. According to Faegri and Iversen they are called: baculae, scabrae and F2 clavae, echinae, gemmae, verrucae (PI. I, t/m 7) (for descrip- tions see glossary). Psilate pollen grains have no structure elements on the tectum (PI. I, FI).

Structure elements on the top of the tectum may also be arranged in If different structure types (reticulum, striae). a tectum is present, corresponding structure types of the columellae are called intra-reticulum, intra-striae. Sometimes columellae can give an impression of a reti-

“ culum. This is, however, a pseudo-reticulum” in which each columella the between the “muri”. represents a “lumen” and space columellae, the A real reticulum is always formed by several structure elements.

In the present study no difference is made between structure and sculpture. According to Potonie (1934), all elements outside the tectum form the sculpture of a pollen grain. Potonie tried to give sharp de-

of these finitions terms, but admitted at the same time, that structure and into each other. Faegri and Iversen sculpture pass (1950) also that and confuse. For that stated, structure sculpture are easy to reason it seems better to speak of structure elements and structure only. CHAPTER VII

GLOSSARY

Annulus (Iversen and Troels-Smith 1950) (PI. I; G 4a en b)

Area which surrounds and is a porus distinguishedby a thickening or a thinning

of the ektexine; thus forming a prominent or depressed margin of the latter.

Aperture (Faegri and Iversen 1950)

weak of ektexine Any performed part the or endexine of a pollen grain (e.g-

colpus, colpus transversalis).

Atrium (PL I; 5a, b en c)

A inside caused cavity a composite aperture by a separation between two

layers of the exine.

Bacula - pi. Baculae (Iversen and Troels-Smith 1950) (PI. I; F 6)

Structure elements with least one dimension at 1 or larger in the shape

of rods. Occur on the tectum only.

Baculate (Iversen and Troels-Smith 1950)

Pollen grains provided with baculae.

Caput - pi. Capita (Erdtman 1952)

Upper part of a pilum.

Clava - pi. Clavae (Iversen and Troels-Smith 1950) (PI. I; F 5)

Structure elements with least one dimension 1 in the at fi or larger shape

of clubs. Occur on the tectum only.

Clavate (Iversen and Troels-Smith 1950)

Pollen grains provided with clavae.

Collum (Erdtman 1952)

Lower part of a pilum; homologous with columella.

Columella — pi. Columellae (Iversen and Troels-Smith 1950)

Lower part of a pilum. Columellae bear the tectum. In 1956 Faegri used

the for term as a synonym pilum.

Colporate (Erdtman 1945)

Pollen grains with composite apertures.

Colpus - pi. Colpi (Erdtman 1943) (PI. I; A2 and Cl)

of Longitudinal apertures the ektexine. Length : breadth > 2.

Colpus transversalis (Erdtman 1943) (PI. I; D 1, 2, 3)

Aperture of the endexine perpendicular to the colpus. Appears in composite

apertures only.

Composite aperture (Erdtman 1952) (PI. I; D 1, 2, 3)

Ektexine aperture combined with an endexine aperture (apertures not con-

gruent).

Costa - pi. Costae (Faegri and Iversen 1950) (PI. I; C 4 and D 4, 5, 6)

Thickenings of the endexine.

Costae circulares (D5): Thickened edges of circular colpi trans\ ersales. 16 w. PUNT

Costae colpi (C4c): Thickened endexine below the edge of colpi.

Costae equatoriales (D6): Thickened edges of colpi transversales extended along the

equator. Costae pori (C4c): Thickened endexine below the edge of pori. Costae transversales (D5): Thickened edges of colpi transversales.

Croton-pattern (Erdtman 1952) (PI. I; E4)

Structure elements in rings of 5 or 6 around a circular area.

Echina - pi. Echinae (Wodehouse 1928) (PI. I; F7)

Structure elements with at least one dimension 1 or larger in the shape

of spines. Occur on the tectum only.

Echinate (Wodehouse 1928)

Pollen grains provided with echinae.

Ellipsoid

with and short axis. Inaperturate pollen grains a long a

Endexine (Erdtman 1943)

Inner part of the exine.

Ektexine (Erdtman 1943)

Outer of the exine. part

Equatorial axis (Van Zinderen Barker 1953) (PI. I; 3E and 4E)

The line perpendicular to the Polar axis in the equatorial plane.

Exine (Fritzsche 1837)

The outer, usually resistant, layer of the wall of a pollen grain.

Gemma — pi. Gemmae (Iversen and Troels-Smith 1950) (PI. I; F4)

Structure elements with least dimension 1 of which the at one or larger

lower parts are constricted. Occur on the tectum only.

Gemmate (Iversen and Troels-Smith 1950)

Pollen with grains provided gemmae.

Inaperturate (Iversen and Troels-Smith 1950)

Pollen grains without apertures.

Intectate (Iversen and Troels-Smith 1950)

Capita of the pila covering less than 80 % of the surface.

Intra-reticulate (Faegri and Iversen 1950)

Columellae inside the tectum form a network.

Intra-striate (Faegri and Iversen 1950)

Columellae inside the tectum stand in rows.

Lumen - pi. Lumina (Potonie 1934)

Spaces between the muri of a reticulum.

Margo (Iversen and Troels-Smith 1950)

Area which surrounds a colpus and is distinguished by a thickening or thinning

of the thus of ektexine; forming a prominent or depressed margin the latter.

Membrana granulata (Erdtman 1952) (PI. I; C2)

Colpus or porus membrane (= endexine) with some scattered structure

elements. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 17

Murus — pi. Muri (Potoni6 1934)

Ridges separating the lumina of a reticulum.

Operculum (Wodehouse 1928; Faeori and Iversen 1950) (PI. I; C3)

Isolated part of the ektexine which is separated from the edges of a colpus

in which the ektexine is or porus by a narrow zone missing or greatly reduced.

Os — pi. Ora (PI. I; D3, o)

of which is formed of That part a composite aperture by the crossing the colpus

and the colpus transversalis.

Periporate (Iversen and Troels-Smith 1950)

Pori distributed the surface of T uniformly over a pollen grain.

Pilum — pi. Pila (Erdtman 1952) (PI. I; F8)

Structure elements of swollen and basal consisting a apex (caput) a cylindrical

part (collum, columella). Occur on the endexine only.

Polar Area Index = P.A.I. (Iversen and Troels-Smith 1950) (PI. I; B3)

distance between the ends of furrows and The proportion of the greatest two

the greatest breadth of the pollen grain (usually the Equatorial axis).

Polar axis (Erdtman 1943) (PI. I; A3p and A4p)

line the of The perpendicular connecting poles a pollen grain.

Porus - pi. Pori (Erdtman 1943) (PI. I; A1 and Cl) of ektexine. breadth 2. Circular apertures the Length : <

Psilate (Wodehouse 1928) (PI. I; FI)

Surface of tectum smooth.

Reticulum (Potonie 1934) (PI. I; E3)

Structural pattern in the form of a network in which columellae represent

the muri of the reticulum.

Scabra - pi. scabrae (Iversen and Troels-Smith 1950) (PI. I; F2)

elements visible but smaller than 1 Occur the Structure /i. on tectum only.

Scabrate (Iversen and Troels-Smith 1950)

Pollen grains provided with scabrae.

Sculpture (Potonie 1934)

A term proposed by Potonie for the joint structure elements outside the tectum

(p. 14).

Stephanocolpate (Iversen and Troels-Smith 1950)

Pollen grains with more than three colpi perpendicular to the equatorial plane.

Stephanocolporate (Iversen and Troels-Smith 1950)

Pollen grains with more than three composite apertures.

Stephanoporate (Iversen and Troels-Smith 1950)

than three in the Pollen grains with more apertures equatorial plane.

Stria - pi. Striae (Iversen and Troels-Smith 1950)

Structure elements standing in rows forming narrow grooves (Jt parallel).

Striate (Iversen and Troels-Smith 1950)

Pollen grains with striae. 18 w. punt

Structure

of Form and arrangement the structure elements.

Structure elements

Individual elements either on the endexine or on the tectum.

Syncolpate (Iversen and Troels-Smith 1950)

Colpi anastomosing at the poles.

Tectate (Iversen and Troels-Smith 1950) (PI. I; El)

and 80 of the surface The capita of pila are fused cover together % or more

of a pollen grain.

Tectum (Iversen and Troels-Smith 1950) (PI. I; El)

The membrane outside the endexine formed by fused capita of pila.

Tectum perforatum (Iversen and Troels-Smith 1950) (PI. I; E2)

The tectum is not completely closed. Small holes are present.

Tegillate (Erdtman 1952)

The capita of the pila are laterally united or fused and cover less than 80 %

of the surface of a pollen grain.

Tricolpate (Iversen and Troels-Smith 1950)

Pollen grains with three colpi perpendicular to the equatorial plane.

Tricolporate (Iversen and Troels-Smith 1950)

Pollen grains with three composite apertures.

Triporate (Iversen and Troels-Smith 1950)

Pollen grains with three pori in the equatorial plane.

Verruca - pi. Verrucae (Iversen and Troels-Smith 1950) (PI. I; F3)

with least dimension 1 in the of Structure elements at one /i or larger shape

warts. Occur on the tectum only.

Verrucate (Iversen and Troels-Smith 1950)

Pollen grains provided with verrucae.

Vestibulum (Iversen and Troels-Smith 1950) (PI. I; C5a, b)

caused between of the exine. Cavity inside a porus, by a separation two layers

CHAPTER VIII

RESULTS

A. POLLEN GRAINS OF THE EUPHORBIACEAE

Pollen grains of the Euphorbiaceae show a number of types, which can be distinguished more or less clearly. Generally pollen grains of the The species inside one genus belong to same pollen type. dimen- but in the sions and proportions may differ, principle pollen grains identical. In different in are some larger genera pollen types occur one More often find Phyllanthus). we that different genera genus ( Tragia , the it is it is possess same pollen type. Consequently not possible, as POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 19 with the in Acanthaceae, to place a plant instantly a genus by means of its pollen grains. within For the greater part the pollen types the subfamilies Phyllan- thoideae and Crotonoideae can be distinguished clearly from each other. Some show Clutia types, however, some affinities; e.g. type (p. 77) with Phyllanthus pentaphyllus subtype (p. 24), and Amanoa type (p. 33) with Sumbavia type (p. 69).

According to the system of Iversen and Troels-Smith (1950) the following principal types occur;

inaperturate, periporate, triporate, stephanoporate, tricolpate, stephanocolpate, tricolporate, stephanocolporate.

Pollen grains with composite apertures occur most frequently. Especially the number of tricolporate pollen grains is large. The shape varies from perprolate (P; E > 2,00) to oblate E In (P : = 0,50-0,75). polar view the pollen grains are mostly convex triangular. In some cases the circumference is triangular (dClutia type), circular (Moultonianthus type) or three lobed (Omalanthus nutans subtype). The but sometimes broad Amanoa colpi are usually narrow, ( type,

Plukenetia type). In many types the colpi are accompanied by costae colpi ( Antidesma type, Mallotus type). The P.A.I. diverge from large (> 0,7) to syncolpate. Syncolpate

pollen grains are, however, rarely found in the Euphorbiaceae (Amperea type)-

Colpi transversales, if present, can be of great diagnostical value.

Shape and size are characteristic for several pollen types (Securinega type, Hippomane type). of often the Pollen grains Euphorbiaceae are tectate. Sometimes

columellae supporting the tectum are so small that they are barely

visible (Alchornea type, Ricinus type). If the pollen grains are intectate, reticulum. In few the they generally possess a a cases only pollen grains

are intectate, pilate (some Phyllanthus species, Tragia fallax type). On

the tectum structure elements of different shape may be found; e.g. clavae, baculae, echinae, etc.

The is structure which meet in croton-pattern a type we many of the Crotonoideae. Outside the this genera Euphorbiaceae structure type is found in Buxaceae and Thymelaeaceae (Erdtman 1952).

In the following treatment of the investigated material the pollen

grains are first divided into the two subfamilies:

a. Phyllanthoideae

b. Crotonoideae

these subfamilies the Inside pollen grains are discussed according

to their similarity in type. in Different pollen grains are placed different pollen types. So the

type unit has been chosen as the base of the classification. Descriptions therefore extensive If of a type are as as possible. the differences are 20 w. PUNT

ofminor importance, the pollen grains are placed in subtypes. Several have characters in To the types can some common. express corre- spondences, these types are assembled in configurations. After the diagno- of the is the ses pollen groups comment given on pollen morphologic

characters, mostly in their relation to other pollen groupings. Besides this in taxonomic discussion is in which comment many cases a added, the value of pollen morphology in taxonomic problems is discussed.

B. DISCUSSION OF THE RESULTS

a. Phyllanthoideae

Antidesma configuration

with Polar axis Tricolporate or stephanolcolporate (4). Pollen grains a larger than the Equatorial axis. P. rarely shorter than the E. (e.g. Phyllanthus acidus sub- type). Colpus transversalis usually with costae.

Pollen grains reticulate or not reticulate; never echinate.

The Antidesma configuration is characterised by its prolate shape of the pollen grains. The Polar axis is usually larger than the Equatorial axis. In the Phyllanthus acidus subtype (p. 26) only the pollen grains are spheroidal or slightly oblate spheroidal. However, the pollen grains much better resemble so the Securinega subtype, that it seems to place them in the same type. The of the the three main types configuration are Antidesma type, the Securinega type and the Dicoelia type. The three types are closely related and have several characters in common e.g. shape, costae colpi and costae transversales. The other types resemble the main types

~~ but lack of the characters one important e.g. costae (Heywoodia type, the p. 30) or have special characters (verrucae in Zimmermannia

type, p. 29).

Fig. 2

The differences between the subtypes are rather faint and difficult

to define and separate. The most reliable character for determination

and separation is found in the colpus transversalis. These apertures

are bordered by costae which make them distinctly visible. In some subtypes (e.g. Antidesma subtype) the rims of the costae transversales ends of the run parallel and the outer colpus transversalis are diffuse. Most Phyllanthus species have costae transversales with rounded ends. in The outer ends of the colpus transversalis are that case distinct and

frequently even closed. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 21

Antidesma type

Tricolporate; perprolate to prolate spheroidal.

Colpus transversalis small or narrow elongated; costae.

costae Colpi narrow; colpi. Tectate; psilate. Mostly not reticulate; rarely indistinct reticulate.

The Antidesma type differs from the Dicoelia type (p. 28) by the shape and dimensions of the colpus transversalis. In other characters

the two types cannot be differentiated. From the the differs Securinega type Antidesma type not only by the

shape of the colpus transversalis but also by the structure of the exine.

Taxonomic discussion

The in the Antidesma be divided into plants type can two groups. combines the Antidesma The first group subtype with the Baccaurea and the second includes the subtype group two Phyllanthus subtypes.

The first group comprises most of the genera which Pax and K. Hoffmann (1922, 1931) united in the subtribe Antidesminae. The

Antidesminae are chiefly characterised by the inflorescense which is

catkin-like or in slender spikes. The following characters are of importance too;

1. The male flowers have only few (six or less; usually five) rudiment stamens round an ovarium rudiment (in Aporosa the ovarium small is or absent).

2. Usually a disc is present. 3. In the female flowers disc be the a may present; styles are usually bifid. almost dioecious. All the 4. The plants are nearly genera are in Old World found the except Hyeronima, which is the American representative of Antidesma (Bentham, 1880).

Mueller of Chonocentrum was first recognised by as a species Drypetes. Pax and K. Hoffmann (1922, 1931) separated the plant from this and it in the of Pollen of the genus placed vicinity Discocarpus. grains

latter genus are however quite different. Chonocentrum differs from Discocarpus by the following characters:

1. Petals are never present.

2. The stamens are not connate but free.

Some included in the Antidesminae Pax and K. Hoff- genera by without mann possess pollen grains an Antidesma type. As for the genera Richeria and related Dicoelia, Richeriella they belong to types. Martretia and Hymenocardia have totally different pollen grains. The second of the Antidesma includes of group type many species of Phyllanthus. Also pollen grains Reverchonia possess the Phyllanthus

In the is related to pentaphyllus subtype. many respects genus Phyllanthus. The branching of the plants, however, is not phyllanthoid. The male disc, always present in'Phyllanthus, is rather indistinct. The two stamens

are inserted on a thick disc-like tissue. As in Phyllanthus there is no

ovarium rudiment, while in the female flowers a disc is present. 22 w. PUNT

Antidesma subtype

Pollen grains tricolporate; perprolate - prolate. Colpus transversalis long; outer ends indistinct and diffuse. Edges of the costae transversales parallel.

The pollen grains are strongly elongated and have narrow elongated colpi transversales. referred Though always to the genus Securinega, Securinega congesta has pollen grains largely different from the other pollen grains in the The P: E and transversalis genus. large narrow elongated colpus place the pollen grains straight into the Antidesma subtype.

Antidesma bunius (Linn.) Spreng. Antidesma subtype; perprolate.

PI. 2 P = E = P:E = Java [U] II, 37,5 n 18,5 n 2,04. P.A.I. m:e < 0,5 = 0,25.

Antidesma venosum Tul. Antidesma subtype; prolate.

= Stolz 476 P 19 E = P:E = [U] fi 13 n 1,50. Antidesma Elmer Antidesma agusanense subtype. Idem Antidesma Elmer 15881 [U] venosum. Antidesma diandrum (Roxb.) Roth Antidesma subtype. Hohenacker 167 Idem Antidesma [U] venosum. Antidesma edule Merr. Antidesma subtype.

Ramos 1083 [U] Idem Antidesma venosum. Antidesma ghesaembilla Gaertn. Antidesma subtype. Hort. 1897 Idem Antidesma Calcutta [U] venosum. Antidesma membranaceum Muell. Arc. Antidesma subtype.

Eels 126 [U] Idem Antidesma venosum. Antidesma obovatum J. J. Smith Antidesma subtype.

Versteeg 1789 [U] Idem Antidesma venosum. Hyeronima alchorneoides Allem. Antidesma subtype. Krukoff 6110 P = E = P:E = [U] 28,5 fi 12 n 2,20. Hyeronima laxiflora (Tul.) Muell. Arg. Antidesma subtype. Sandwith 544 [U] PI. II, 1 Thecacoris leptobotrya (Muell. Arg.) Antidesma subtype. Brennon

Zenker P = 36 E = P;E = 23 [U] n 17,5 2,04. Cyathogyne spathulifolia Pax Antidesma subtype.

Schlieben P = 40 E = P:E [P] fi 20,5 fi = 1,94. m:e± 0,5. Cyathogyne viridis Muell Arg. Antidesma subtype.

F.H.I. Too for 3936 [K] young measurements. Apodiscus chevalieri Hutch. Antidesma subtype.

Pobequin 1909 [P] P = 30 n E = 19 fi P:E = 1,58. Protomegabaria macrophylla Hutch. Antidesma subtype.

Andoh 5474 PI. 3 P = E 19 P:E [K] II, 27,5 fi = n = 1,45. Spondianthus preussii Engl. Antidesma subtype.

Versuchsanst. 164 P = 26 E = P;E = [U] n 18,5 n 1,40. Maesobotrya floribunda Benth. Antidesma subtype.

Lebrun 1039 P = 21 E = 15 P;E = [U] iu /a 1,40. Maesobotrya dusenii (Pax) Hutch. Antidesma subtype. Zenker 221 [U] Securinega congesta Muell. Arg. Antidesma subtype.

Black 2432 [U] P = 45 fi E = 26 n P:E = 1,73.

m:e < 0,5.

Baccaurea subtype

Pollen grains tricolporate; subprolate - prolate sphaeroidal. Colpus transversalis small. Outer ends indistinct and diffuse. Edges of the costae transversales parallel. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 23

plate ii. 1. Hyeronima laxiflora; 2. Antidesma bunius; 3. Protomegabaria macrophylla; 4. Aporosa lindleyana; 5. Phyllanthus pentaphyllus; 6. Baccaurea sumatrana; 7. Reverchonia arenaria; 8. Margaritaria nobilis; 9. Phyllanthus niruri. 24 W. PUNT

In its exine structure this subtype is related to the Antidesma subtype. and the The pollen grains, however, are less elongated colpus trans- versalis is smaller.

Baccaurea sumatrana (Miq,.) Muell. Arg. Baccaurea subtype; subprolate.

Hort. VI 185 A 6 19 E 15 P:E = Bog. C. [U] PI. II, P = ft = ft 1,33.

P.A.I. = 0,35 — 0,3. Baccaurea javanica (Blume) Muell. Arg. Baccaurea subtype. Hort. Bog. 344 [U] Idem Baccaurea sumatrana.

Baccaurea racemosa (Reinw. ex Blume) Baccaurea subtype. Muell. Arg.

Hort. Bog. 553 [U] Idem Baccaurea sumatrana. Baccaurea oxycarpa Gagnep. Baccaurea subtype. (= Gatnaia annamica Gagnep.)

P:E = P = 21 E = 16 Eberhardt 3042 [P] ft n 1,31. Aporosa lindleyana (Wight) Baill. Baccaurea subtype.

Hohenacker PI. 4 P = 19 E = P;E = 352 [U] II, n 17,5 ft 1,10.

P.A.I. = 0,2 — 0,25 Aporosa dioica (Roxb.) Muell. Arg. Baccaurea subtype. King 298 [U] Idem Aporosa lindleyana. Aporosa frutescens Blume Baccaurea subtype. Herbr Utrecht 022876 Idem Aporosa lindleyana.

Collector unknown.

Phyllanthus pentaphyllus subtype

Pollen grains tricolporate; prolate - subprolate.

Colpus transversalis small; outer ends almost distinct. Edges of the costae transversales rounded at the end.

The difference with the Antidesma subtype and Baccaurea subtype is found in the colpus transversalis.

There is also a relation with the Phyllanthus niruri subtype. The

latter subtype, however, is 4 — colporate.

Phyllanthus pentaphyllus Wright ex Phyllanthus pentaphyllus subtype; prolate.

Grisebach P = E = = 32 /I 22,5 n P:E 1,43.

Boldingh 7378 [U] PI. II, 5 m:e = 0,5 P.A.I. = 0,3. Phyllanthus sublanatus Schum. et Thonn. Phyllanthus pentaphyllus subtype. 1010 30 P:E de Wit P = 45 E = = [WAG] 'n n 1,50.

P.A.I. = 0,45. Phyllanthus stipulatis (rap.) Webster Phyllanthus pentaphyllus subtype.

13 P = E = P:E = Geyskes [U] 24 ‘n 17,5 n 1,37.

Phyllanthus amarus Schum. Phyllanthus pentaphyllus subtype.

= *E = 27 P:E = B. W. 10 [U] P 35,5V n 1,32. de Wit 474 [WAG] Reverchonia arenaria A. Gray Phyllanthus pentaphyllus subtype.

Warnock PI. 7 P = E'= 30 P:E = 10723 [U] II, 37 n 1,60.

m:e = ca. 0,4. Savia erytroxyloides Griseb. Phyllanthus pentaphyllus subtype.

1434 P = E*= P:E Wright [BM] 32 ii 26 n = 1,24.

P.A.I. = m:e < 0,5 0,25.

Phyllanthus niruri subtype

Pollen grains stephanocolporate (4); prolate. Colpi transversales; costae transversales. Edges of the colpus transversalis rounded at the end.

Except for the number of colpi the Phyllanthus niruri type is in all its characters identical with the Phyllanthus pentaphyllus subtype. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 25

As in the columellae Phyllanthus pentaphyllus subtype the are sometimes

fairly coarse. The surface pattern seems to form a reticulum. This is in however a “pseudo-reticulum” (p. 14). Only Phyllanthus niruri real reticulum a formedby a regular arrangement of several columellae

was seen. This reticulum was only to be seen with a phase-contrast

microscope and then very indistinctly.

Phyllanthus niruri Linn. Phyllanthus niruri subtype.

Fuertes 89 PI. 9 P = 39 E = P:E = [U] II, n 21 n 1,86.

P.A.I. > 0,5. Indistinct intra-reticulate. Phyllanthus guianensis Klotz. Phyllanthus nirwri subtype.

B.W. 4599 P = 36 [U] /z. Phyllanthus hyssopifolioides H.B.K. Phyllanthus nirwri subtype.

Focke 1278 P = 30 E = 18 P:E = [U] n n 1,67. Phyllanthus urinaria Linn. Phyllanthus niruri subtype. Too Lanjouw 246 [U] young.

Chonocentrumcyathoforum (Muell. Arg.) Antidesma type-, tricolporate.

Pierre ex Pax et K. Hoffmann Colpus transversalis with costae. Spruce 3781 [P] P:E > 1. Too it definite young to give a place

in the Antidesma type.

Securinega type

Tricolporate or stephanocolporate (4); subprolate - sphaeroidal (rarely oblate sphaeroidal).

Colpus transversalis small, circular or broad elliptic; costae.

Colpi narrow; costae colpi usually developed. Intectate: lumina distinctly reticulate; 1-2 n- Pollen small 30 15—25 grains (smaller p, usually μ).

has This type small pollen grains with circular or broad elliptic

colpi transversales. The reticulum is distinct and usually fairly coarse in comparison with the small pollen grains.

Taxonomic discussion

The besides the Securinega type comprises, genus Securinega (and of and the small Flueggia), many species Phyllanthus generaMargarilaria and Astrocasia. These genera are all closely related (Webster, 1956).

The in Pax’s close to genus Aporosella, system placed Aporosa, should be reduced to a section of Phyllanthus according to Webster One of (1956). the principal reasons which led him to this conclusion

is the close relation to Phyllanthus acidus. In fact, the pollen grains of Phyllanthus elsiae, belonging to the section Aporosella, are closely

related to those of Phyllanthus acidus (p. 26).

Securinega subtype

Pollen grains subprolate - prolate sphaeroidal. transversalis circular broad Colpus or elliptic.

Pollen the have grains of Securinega subtype always a P: E > 1.

The shape of the colpus transversalis is circular to broad elliptic.

Securinega suffruticosa (Pallas) Rehder Securinega subtype.

P = E = P:E = Cantonspark (Baarn) 22,5 /a 2\/j. 1,08.

= — Lumina P.A.I. 0,25 0,3. 1-2 fi. 26 w.punt

Securinega ramiflora (Aiton) Muell. Arg. Securinega subtype.

= £ = P:E = Linsley Gressitt 229 [U] P 23,5 fi 20/* 1,17. Securinega neopeltandra (Griseb.) Urban Securinega subtype.

ex Pax et K. Hoffmann

Shafer 12080 [U] P:E = 1,18 Lumina < 1 fi.

Securinega virosa (Roxb. ex Wiled.) Baill. Securinega subtype. Reichs-Kolon. 506 [U] PI. Ill, 2

Margaritaria nobilis Linn. f. Securinega subtype.

PI. 8 P = E = P:E = Soeprata 2D [U] II, 22,5 n 19,5 /a 1,15.

m:e > 0,5 P.A.I. = ca. 0,25.

Lumina 1 ca. /a. Astrocasia tremula (Griseb.) Webster Securinega subtype.

Gaumer Sens 1261 P = 29 E = P:E = et [K] 25,5 n 1,14.

m:e ca. 1 P.A.I. = 0,3. Lumina 1-2 fi. Phyllanthus reticulatus Poir. Securinega subtype.

de Wit 128 P = 18 E = P;E = [WAG] n 16,5 ft 1,09.

Bakhuizen d. Brink 3540 P.A.I. = Lumina 1 v. [U] 0,25. ca. fi. Phyllanthus discoideus Muell. Arg. Securinega subtype.

= E = 18 P:E = Leeuwenberg 2789 [U] P 22,5 n n 1,25.

Costae colpi. P.A.I. = 0,3. Lumina 1-2 fi. Phyllanthus capillaris Schum. et Thonn. Securinega subtype.

De Wit 229 [WAG] PI. Ill, 1 Stephanocolporate (4) or tricolporate.

P = 21,5 n E = 20,5 n P:E = 1,05.

P.A.I. = 0,5. Phyllanthus acuminatissima C. B. Robb. Securinega subtype.

Elmer P = E = 18 P:E 15662 [U] 22,5 n n = 1,25.

P.A.I. = Lumina 1 0,25. ca. fi. Richeriella gracilis (Merr.) Pax et Securinega subtype?

K. Hoffmann Too for reliable young measurements, Hyting 65438 [K] but colpus transversalis distinctly cir- cular.

Phyllanthus acidus subtype

Pollen grains tricolporate; sphaeroidal - oblate sphaeroidal. Colpus transversalis circular.

Unlike the Securinega subtype the pollen grains of the Phyllanthus

acidus subtype are spheroidal or sometimes slightly oblate spheroidal.

The colpus transversalis is always circular. The exine structure is in

all the in the respects same as Securinega subtype.

Phyllanthus acidus (Linn.) Skeels Phyllanthis acidus subtype.

566 P = E P:E 1. Versteeg [U] = 17,5 n = ca.

= P.A.I. 0,2 — 0,3. Phyllanthus muellerianus (O. Kuntze) Phyllanthus acidus subtype. Exell Too Colpi very short. young. Zenker 253 [U] Phyllanthus elsiae Urban Phyllanthus acidus subtype.

and Urban 4789 PI. 3 P = E = 20 P.A.I. Krug [L] HI, n. > 0,5.

Richeria type

Tricolporate; subprolate.

Colpus transversalis narrow; costae.

Colpi narrow.

Tectate (?); intra-reticulate. Lumina ca. 1 fi.

The Richeria type is an intermediate type between the Antidesma and type the Securinega type. The narrow elongated colpus transversalis POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 27

platein. 1. Phyllanthus capillaris; 2. Securinega virosa; 3. Phyllanthus elsiae; 4. Drypetes glauca; 5. Actephila excelsa; 6. Andrachne phyllanthoides. 28 w. PUNT is of the Antidesma but the typical type, distinct, rather coarse reticulum characteristic is of the Securinega type.

Taxonomic discussion

Pax Hoffmann well Bentham and K. (1931) as as (1880) placed this in the Antidesminae. It occurs in the New World. genus

Richeria laurifolia Baill. ex Muell. Arg. Richeria type; prolate.

= = Krukoff 8776 P = E P:E [U] 29 fi 24 1,21.

Lumina ca. 1 fx.

Dicoelia type

Tricolporate; prolate — subprolate. Colpus transversalis broad and elongated to broadly elliptic; costae.

Colpi narrow; costae colpi. Tectate, psilate; sometimes intra-reticulate.

Pollen of medium size - 50 grains (ca. 25 fi /*).

The Dicoelia type possesses elements of the Antidesma type as well of Polar axis as the Securinega type. The pollen grains have always a of at least 25 between 30 and 55 The trans- /u; usually fi pt. colpus versalis is large; broad and elongated or broadly elliptic, but never circular.

Taxonomic discussion

Pax and K. Hoffmann (1922, 1931) included the genus Dicoelia in the Antidesminae for its elongated inflorescences. However, the loose, often androgynous clusters along the rachis of the racemes is

different from inflorescence in the any Phyllanthoideae (Bentham 1880).

Dicoelia subtype

Colpus transversalis broad and elongated; m:e < 0,4. Usually not intra-reticulate.

Dicoelia affinis J. J. Smith Dicoelia subtype.

Hallier P = 44 E = 32 P:E = 1255 [U] // 1,37.

m:e < 0,4 P.A.I. = 0,3. Indistinct reticulate.

Drypetes glauca Vahl Dicoelia subtype.

PI. 4 P = 34 E P:E Sintenis 5111 [U] Ill, n = 27 n = 1,26.

m:e < 0,25 P.A.I. = 0,25.

Drypetes macrophylla (Blume) Pax et Dicoelia subtype.

K. Hoffmann P = 45 E = 40 P:E = n n 1,16.

Bogor VIII F. 48 [U] m:e < 0,4 P.A.I. = 0,35. Intra-reticulate.

Drypetes laterifolia (Swartz) Krug et Dicoelia subtype.

Urban

Fuertes 824 [U] Drypetes variabilis Uitt. Dicoelia subtype. B.W. 6481 [U]

Andrachne subtype

Colpus transversalis broadly elliptic; m:e = ca. 0,5 or larger. Usually intra-reticulate. POLLEN MORPHOLOGY OF THE EUPHORBLACEAE 29

Andrachne phyllanthoides (Nutt.) Mueix. Andrachne subtype.

Arc. P = 45 E = P:E = /i 35,5 n 1,27.

= Bush 14843 [U] PI. Ill, 6 m:e 0,5 P.A.I. = 0,2. Indistinct costae colpi. Andrachne telephioides Linn. Andrachne subtype. Dalmatic 1937, 50 [U] Intra-reticulate. Andrachne colchica Fisch. et Meyer Andrachne subtype. Cult. Hort. Canton (Baarn) 4884 [U] Andrachne aspera Spreng. Andrachne subtype.

Pappi 4892 [U] P = 43 ft E = 31 n P:E = 1,40.

m:e > 0,5. P.A.I. = 0,3. Longitudinal striation. Actephila excelsa (Dalz.) Muell. Arg. Andrachne subtype.

Hort. VII B. 271 PI. 5 P = 48 E = 37 P:E = Bog. [L] Ill, n n 1,36.

P.A.I. = 0,3. Costae colpi. Poranthera corymbosa Brong. Andrachne subtype.

Constable 30096 P = 34 E = P:E [U] n 29,5 /j. = 1,15.

m:e ca. 0,5 P.A.I. =0,25. Tectum perforatum; lumina of the intra-reticulum 2-3 /i. Poranthera microphylla Brong. Andrachne subtype.

P E = P:E = Hastings [U] = 24 ft 19,5 n 1,23. lumina Tectate; intra-reticulate; ca. 1 p.

Zimmermannia type

Tricolporate; prolate spheroidal. Colpus transversalis small; costae.

Colpi narrow. Tectate; verrucate.

The the in Zimmermannia type is only type the Phyllanthoideae with

verrucae. Except for this remarkable character the pollen grains belong without doubt in the Antidesma configuration.

Zimmermannia capillepes Pax Zimmermannia type.

PI. 1 = FI. Usambarica 5862 P 58 E = 51 P:E = [BM] IV, /e /e 1,12.

m:e > 0,5 P.A.I. = 0,25.

Leptonema type

Tricolporate; subprolate.

Colpus transversalis broad and large; costae narrow. absent. Colpi narrow; costae colpi columellae Tectate; psilate. The are so small, that they are hardly visible.

has The Leptonema type some relation with the Dicoelia type (p. 28). The type misses, however, the costae colpi. It differs from the Antidesma and type (p. 21) by the broad elongated colpus transversalis.

Taxonomic discussion

Pax and K. Hoffmann (1922, 1931) placed in the subtribe Glochi-

diinae Leptonema together with Glochidion and Breynia. It seems better in the of to keep Leptonema vicinity Phyllanthus and its allied genera, as stated by Bentham (1880).

Leptonema venosa (Poir.) A. de Juss. Leptonema type.

D’Alleizette 6405 Mad. P = E = P:E = 27 ju 22,5 yu 1,21.

Nov. 1905 [L] PI. IV, 2 m:e <0,5 P.A.I. = 0,5. 30 W. PUNT

Pleiostemon type

Tricolporate; prolate spheroidal.

m:e 6-8 Colpus transversalis; costae; larger 1; m = fi.

Colpi narrow; costae colpi. P.A.I. small. Pollen grains sometimes syncolpate. Tectate; psilate.

the The Pleiostemon type belongs undoubtedly to Antidesma con- figuration. The colpus transversalis however differs from all other types by its meridional elongation. The m : e is larger than 1. More- the the over, colpi are very long. Sometimes pollen grains are even syncolpate (colpi anastomosing at the poles).

Taxonomic discussion

The this without doubt genera belonging to type are related to and its allied Mueller reduced the Phyllanthus genera. (1866) genus Bentham Pleiostemon to a section of Phyllanthus and (1880) referred it to Securinega. In the system of Pax and K. Hoffmann (1931) Pleioste-

is maintained close On the other mon as a genus to Phyllanthus. hand, is found in subtribe in Lingelsheimia the Drypetinae their system.

Corresponding characters are:

1. In and the male flowers an extrastaminal disc present an ovarium rudiment wanting.

the female 2. In flowers an annular disc and bifid styles present.

3. Calyx is 6-partite (in Pleiostemon the male flower is sometimes

4-5-partite. Petals are absent.

4. Plants monoecious and only found in Africa and Madagascar (.Dangyodrypetes ).

Pleiostemon verrucosus Sonder Pleiostemon type. PI. 3 312 P = E P;E Cooper [BM] IV, 20 n = 19,5 fi = 1,03

m:e > 1 P.A.I. < 0,2.

Lingelsheimia frutescens Pax Pleiostemon type.

Lebrun PI. 4 P = E = P:E = 3855 [K] IV, 22,5 fi 21 n 1,07.

P.A.I. = 0,1.

Dangyodrypetes ambigua L£andri Pleiostemon type.

Serv. Eaux Forests E = P:E = et 7675 [P] P=24 n 22,5 n 1,07. P.A.I. almost syncolpate-syncolpate.

Heywoodia type

Tricolporate; prolate spheroidal.

Colpus transversalis broad; costae absent; m:e ca 1.

Colpi narrow; costae colpi absent. Tectate; psilate. Columellae distinct.

As the Polar axis is larger than the Equatorial axis the type is placed in the Antidesma configuration. There is, however, a possibility that Heywoodia is wrongly placed in this configuration because of the

absence of costae.

Heywoodia lucens Sim Heywoodia type.

5133 PI. 5 P = E P:E Bally [K] IV, 27,5 n = 25,5 n = 1,08.

m:e ca. 1 P.A.I. = 0,3. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 31

1. 3. Pleiostemon plate iv. Zi mmermannia capillepes; 2. Leptonema venosa; verrucosus; 4. Lingelsheimia fruticosa; 5. Heywoodia lucens; 6. Amanoa guianensis; 7. Pseudolachno- stylis glauca. 32 w. PUNT

Amanoa configuration

Tricolporate-stephanocolporate (4-5). Pollen grains usually with a P. shorter than the E.

Colpus transversalis usually with costae.

Pollen grains reticulate. Rarely not reticulate (some species of Amanoa and the Discocarpus type).

The Amanoa configuration includes pollen types with a Polar axis shorter than the Equatorial axis and lesser than six (usually 3—4) colpi.

The pollen grains are reticulate except in a few species. These latter have characters in with related species, however, so many common reticulate species, that there is no doubt that they belong to the same

type-

. As in the Antidesma configuration the types are difficult to separate. the Especially Amanoa type and Savia type are closely related.

Taxonomic discussion

The this all related. genera belonging to configuration are closely

The division of the pollen grains into four types is not found again in of Bentham Pax and K. the systems Mueller, and Hoffmann. Mueller (1866) removed Briedelia and Cleistanthus to a distinct subtribe of their valvate all the other on account calyx (nearly genera in Phyllanthoideae have an imbricate calyx). For this reason Pax and K. Hoffmann also these in tribe. (1931) placed genera a special Bentham (1880) took less account of the imbricate calyx and found, in the remaining characters, much affinity with Amanoa. So he placed Briedelia and Cleistanthus in close proximity of Amanoa. The pollen grains of Cleistanthus cannot be separated from those of Savia. Except for the of the the longitudinal striation pollen grains Briedelia type also close related those of the Savia From these results are very to type. it is clear that pollen morphology supports the statement of Bentham. of Bentham (1880) discussed Uapaca in the group the Antidesminae. Pax and K. Hoffmann (1931) established a special subtribe for this the the Savia it genus. Although pollen grains belong to type seems better to this out of the subtribes with Savia The keep genus a type. involucrum and the absence of a disc in the male flowerare characters

too divergent for placing Uapaca in the vicinity of any other genus with a Savia type. K. Hoffmann the In the system of Pax and (1931) remaining genera of the Amanoa configuration are divided into four subtribes. 1. Wielan- diinae. 2. Amanoinae. 3. Discocarpinae. 4. Pseudolachnostylidinae. In these subtribes the do have the following genera not typical characters of the Amanoa configuration.

1. Astrocasia. According to Webster (1956) the genus is related to

Securinega. The pollen grains undoubtedly belong to the Securinega

type. 2. The is classified with Amanoa all Actephila. genus together by

authors. Actephila excelsa, however, possesses pollen grains of the Examination of Dicoelia type. of the pollen grains other species

is necessary. POLLEN MORPHOLOGY OF THE BUPHORBIACEAE 33

3. Chonocentrum. The pollen grains of Chonocentrum belongs without

doubt to the Antidesma type (p. 21).

4. Savia erytroxyloides. Pollen grains of this Savia species belong to the Phyllanthus pentaphyllus subtype.

The have the remaining genera following characters in common:

1. The calyx is 5-partite.

2. Frequently petals are present.

3. Male as well as female flowers have a disc.

4. In the male flowers an ovarium rudiment is present.

5. Stamens are often connated into a column.

6. Seeds never have a caruncula.

Amanoa type

Tricolporate-stephanocolporate (4-5); suboblate-oblate spheroidal.

Colpus transversalis broad; ora large; costae usually present.

Colpi wide; no costae colpi.

Tectate or intectate; reticulate or not reticulate.

If the pollen grains are reticulate the lumina are at least 3 fi in diameter.

not reticulate the structure elements tall When the pollen grains are are and

least 4 at fi. Exine at least 4 very thick, /i.

reticulum and The Amanoa type is characterised by a coarse a thick exine.

of The reticulum the Amanoa type had to be considered as an intra- reticulum since the muri are connected by a thin membrane, which covers the lumina.

Some species of Amanoa lack the coarse reticulum. Amanoa guianensis has with The columellae a tectum provided long baculae or echinae. of Amanoa in and grandiflora are, optical section, gemma shaped inordinate arranged. In both Amanoa species the exine is, however, more than 4 thick. fi

Amanoa Amanoa oblongifolia Muell. Arg. type.

Krukoff 7015 [U] PI. V, 1 P = 33,5 n. E = 43 n P:E = 0,78. Lumina Colpi wide. P.A.I. = 0,25.

up to 11,5 fi. Amanoa grandiflora Muell. Arg. Amanoa type.

Murca Pires 835 P = 39 E = P:E = [U] n 45/i 0,87.

P.A.I. = 0,5. Not reticulate. Columel- lae inordinate gemma shaped, ar- ranged.

Amanoa bracteosa Planch. Amanoa type. E = 80 /i.

D’Alleizette 6392 Lumina to 10 P.A.I. = [L] up fi. 0,4. Amanoa boiviniana Baill. Amanoa type.

D’Alleizette Mad. 1906 P = E = 45 P:E = Nov. [L] 37,5 fi n 0,83.

P.A.I. = 0,4 — 0,5. Lumina to 4 up fi. Amanoa guianensis Aubl. Amanoa type.

S.F. P = 46 E 52 P:E = Bafog 1192 [U] fi = /i 0,88.

Wood Herb. 28 [U] PI. IV, 6 P.A.I. = 0,3. Costae transversalis. Co- short. lumellaevery Baculate-echinate; baculae to 7 Endexine thick. up fi. 34 w. PUNT

reticulatum Pentabrachion (Muell. Arg.) Amanoa type; 3-4 colporate.

Jantzon P = 45 jit E = 48/i P;E = 0,94.

Zenker Lumina 5 P.A.I. = 2982 [L] up to ft. 0,4—0,5. Costae transversales.

Hutch. Amanoa 2-3 Pseudolachnostylis glauca (Hiern) type; colporate.

1181 PI. 7 P 31 E 34 P:E = Lanjouw [U] IV, = n = /i 0,91. Lumina up to 4,5 ft.

Savia type

Tricolporate-stephanocolporate (4); subolate-prolate spheroidal. transversalis small. Colpus usually narrow; ora Rarely colpus transversalis

broad and ora large (Cleistanthus ferrugineus). sometimes Colpi narrow; costae colpi present. Tectate reticulate. Lumina of the reticulum smaller. or intectate; 3 ft or Exine is medium lesser then 4 but still distinct. thick, ft

the Savia In many respects type resembles the Amanoa type. The reticulum lumina of the are, however, distinctly smaller. Since the smaller pollen grains are also relatively this difference is perhaps not offundamental importance, but, besides the smaller lumina, the colpi better are narrow and the ora small, so it seems to separate the pollen the from of Amanoa grains of Savia type those the type. .. _ . Some species with a Savia type (Cluytiandra madagascariensis, Lach-

nostylis hirta) have a Polar axis larger than the Equatorial axis. By this character the pollen grains should be placed in the Antidesma The exine from configuration. structure, however, is quite different the Antidesma configuration and is, on theother hand, in full agreement with the Savia type.

Savia andringitrana Leandri Savia type.

1926 P = 26 E = 29 P:E = Decary [L] ft n 0,88. m;e < 0,5. P.A.I. = 0,4. and short. Lumina Colpi narrow 3 ft. Costae transversales. Savia sessiliflora (Sw.) Wield. Savia type.

1905 P = E = 29 P:E = Eggers [P] 24,5 fi !x 0,85.

P.A.I. = 0,3. Blotia oblongifolia (Baill.) Leandri Savia type.

P = E = P:E = D’Alleizette [L] 25,5 n 28.5 n 0,89.

Mad. 4 Mai. 1918 P.A.I. = 0,45.

short and narrow. Lumina 1-2 Colpi ft. Wielandia elegans Baill. Savia type. 3—4 colporate.

D’Alleizette P 37 E = Seych. [L] = /i = 41,5 n P:E 0,88.

= Lumina P.A.I. 0,65. = 1-2 /a.

Colpi narrow and short. Lachnostylis hirta (Linn, f.) Muell. Arg. Savia type; prolate spheroidal.

= = hirtus Pax P E — P:E [= Discocarpus (Linn, f.) et 37 n- 35 fi 1,05.

K. Hoffmann] P.A.I. = 0,3. Colpus transversalis with

Bolus 2396 Lumina [K] costae. 1-2 fi. Cluytiandra madagascariensis Leandri Savia type; prolate spheroidal.

Mad. P E = 31 P:E = D’Alleizette 6402 [L] = 32 fi n 1,04.

P.A.I. =0,3. Costae transversales. Re- ticulum indistinct. Lumina 1-2 fi.

Cleistanthus winkleri E = Jabl. Savia type. 32 ft. Bogor IX C. 165 A. [U] Costae colpi. Cleistanthus dichotomus J. J. Smith Savia type. Gjellerup 142 [U] POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 35

plate v. 1. Amanoa oblongifolia; 2. Cleistanthus ferrugineus; 3. Uapaca heudelotii; 4. Discocarpus essequeboensis; 5. Briedelia monoica; 6. Breynia fruticosa; 7. Breyniopsis pierrei; 8. Glochidion sericeum. 36 w. PUNT

Cleistanthus ferrugineus Muell. Arg. Savia type; prolate.

Hort. Bogor. IX C. 43 A. [U] PI. V, 2 P = 44 E = 33 P:E = 1,34.

P.A.I. = 0,4 — 0,5.

Colpus transversalis isodiametric; no

Lumina costae; ora large. 1-2 fi. Savia oblate Uapaca heudelotii Baill. type; spheroidal.

Zenker 59 PI. P = E = P:E = [U] V, 3 22 fi 25 n 0,88.

P.A.I. = m:e < 0,5. 0,5. Tectate.

Uapaca kirkiana Muell. Arg. Savia type.

Stolz 622 P = E = P:E = [U] 27 29,5 n 0,93.

Tectate.

Briedelia type

Tricolporate; oblate spheroidal. Colpus transversalis broad; costae.

Colpi narrow at the ends, broadened in the equatorial part. Sometimes costae colpi present. Intectate; reticulate. Lumina small and in chains along the colpi (pseudo- striate). Muri distinct but not tall.

related the Savia The difference This type is closely to type. greatest is found in the longitudinal arrangement of the lumina of the reti- culum. The chains oflumina the striate give pollen grains a appearance, which is, however, only a “pseudo-striation”: a striation not caused by individual columellae but by the lumina of the reticulum which of of several columellae. are, course, composed

Briedelia monoica (Lour.) Merr. Briedelia type.

Endert 1066 PI. 5 P = E P:E E [U] V, 24 ju = 25,5 fi = 0,94.

m:e > 0,5. P.A.I. = 0,35. Lumina

< 1 ft.

Briedelia Blume Briedelia E = 31 glauca type. /a. Winckel 865 B [U] Hook. Briedelia E =31 Lumina 1-2 Briedelia assamica J. D. type. /t. /i. Herb. East Ind. Comp. 4890 [U]

Briedelia Blume Briedelia E = 42 stipularis (Linn.) type. //.

m:e P.A.I. = v. Leeuwen-Reynvaan [U] < 0,5. 0,25. Godefroya rotundata (Jabl.) Gagnepain Briedelia type.

P = E P:E Gourgaud [P] 32 n = 33,5 n = 0,96. Costae P.A.I. = 0,25. colpi.

Discocarpus type

Stephanocolporate (4-5); oblate spheroidal.

Colpus transversalis small; no costae present.

Colpi narrow. No costae colpi present. Tectate, psilate. Not reticulate.

The Discocarpus type is an intermediate type between the types of and the Amanoa configuration the types of the Antidesma configuration.

The small columellae and the absence of a reticulum are characters

of in the in favor placing the type Antidesma configuration. On the other hand the oblate shape, the absence of costae and the 4—5 colpi

are more in agreement with the Amanoa configuration. For these latter better the in reasons it seems to discuss type the Amanoa configuration.

TC THT7SPH Discocarpus essequeboensis Discocarpus type.

= 659 PI. 4 P E = P:E Schomburgk [U] V, 34,5 ft 37/t = 0,94.

Ora small; m:e > 0,5. P.A.I. = 0,6. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 37

Phyllanthus nutans configuration

Pollen grains with an areolate structure.

Taxonomic discussion

Erdtman the After a proposal of Iversen, recommended term areolatus for the structure described under Phyllanthus nutans type (1947). The definition given by him is: “Pollen grains with small

areas separated by small grooves forming a negative reticulum”. Webster that the (1956) states areolate pollen grains are mostly found in the New World. Some species of Phyllanthus in the Old have areolate that World, however, pollen grains are superficially very

similar to those of the New World.

Phyllanthus nutans type

the surface of the is divided into hexa- Periporate; pollen grains pentagons or The in the gons. pori are situated angular points. Pori small.

each of lead the other Intectate. From aperture two rows pila to apertures.

In the centre of the penta- and hexagons the pila form an irregular reticulum.

Phyllantus nutans Sw. Phyllanthus nutans type. PI. axis Shorter axis Hooker, Jamaica [U] VI, 2 Longer 27,5 /r. 25 /*.

ca. 25 pori. Phyllanthus adianthoides Klotzsch Phyllanthus nutans type.

Hulk Diam. = 17 21 [U] /s. Phyllanthus speciosus Jacq,. Phyllanthus nutans type.

Fresh Greenhouse Utrecht Diam. = 20 Pori ca. 15. material, /i.

Dendrophyllanthus type

Tricolporate (?); oblate. Colpus transversalis circular; costae.

of of Colpi very narrow; operculum consisting one row pila. Intectate; not reticulate.

Without doubt the pollen grains are related to the Phyllanthus nutans

type in their exine structure. The surface of the pollen grains is divided into three regions, separated by strings of pila, the “colpi”.

Each “colpus” consists of three rows of pila. If the two outer rows

represent the borders of the colpus, the inner row mustbe taken as an

operculum. However, the space between the rows is so small, that it weak in the can hardly be regarded as a performed part ektexine (see

definition aperture: Glossary). For this reason it is possible to defend the that the of opinion, pollen grains Dendrophyllanthus are triporate.

In that case the rows of pila would only be an ornamental peculiarity.

that in Nevertheless, the rows look so much like real colpi, the author’s it is better maintain the in the of the opinion to pollen grains group tricolporate.

Dendrophyllanthus ripicolus Guill. Dendrophyllanthus type.

Mackee 3629 PI. 3 P = E=27 P:E = [L] VI, 19,5 n n 0,72.

m:e = ca. 1. 38 w. PUNT

Breynia configuration

Stephanocolporate (colpi sometimes with two ora).

Colpus transversalis circular rarely somewhat elliptical; costae.

Colpi narrow and long. Tectate intecta or te.

By its exine structure the Breynia configuration is related to the Antidesma configuration. Most pollen grains, however, have a Polar in axis shorter than the Equatorial axis as the Amanoa configuration. The typical character of the number of colpi with often two circular this colpi transversalis per colpus seem to justify configuration.

Breynia type

Stephanocolporate (colpi diorate); oblate - subprolate. circular transversales have Usually two colpi per colpus, some colpi only one colpus transversalis; costae. sometimes Colpi narrow; costae colpi. reticulate lumina small. Intectate or tectate; or not reticulate;

is the number of The Breynia type easily recognised by large colpi (six or more) and the double circular colpi transversales. In the

species of Breynia one of the two colpi transversales is often reduced.

The remaining endexine aperture is never situated in the equatorial plane but towards the ends of the colpus.

Taxonomic discussion

this have been Hitherto the genera belonging to type never placed in author. Mueller the relation- one group by any (1866) recognised shared ship of Agyneia with Sauropus, which opinion was by Bentham (1880) and Pax and K. Hoffmann (1922, 1931). Breynia and Glochidion,

on the other hand, are always distinguished as genera closely related reduced of to Phyllanthus. Glochidion is even often to a section Phyllanthus. Pax and K. Hoffmann keep Glochidion, Breynia and Breyniopsis in the subtribe Glochidiinae. In the author’s the above should opinion genera other all be placed in one group (either subtribe or taxon). They have the following corresponding characters:

1. The number of sepals is usually six (iGlochidion sometimes fewer).

2. In the male flowers generally three connated stamens form a

column. Connectives are frequently appendiculated. Anthers

extrors. There is no ovarium rudiment nor a disc. As Bentham

of states, the scale-like thickenings at the base of the sepals

Agyneia and Sauropus are not to be regarded as disc glands.

3. In the female flowers disc glands are wanting.

4. The monoecious and plants are generally (Some Glochidion species in Arachnodes, however, dioecious) and only occur the Old World.

Breynia subtype

Pollen grains oblate spheroidal - oblate. lumina 1-2 Intectate; reticulate; //. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 39

Breynia fruticosa (Linn.) Benth. Breynia subtype; oblate. and M. S. Clemens P = E = P:E = J. 3182 [U] 21 fi 27 /x 0,76. Beekler 2 [U] PI. V, 6 Colpi transversales situated almost at the end of the colpi. Colpi not always provided with two colpi transversales.

Colpi 8-10. Lumina 1-2 p.

Breynia racemosa (Blume) Muell. Arg. Breynia subtype; oblate. Bakhuizen d. Brink 5-6 v. [U] colpi. Breynia nivosa (W. G. Smith) Small Breynia subtype. Collector unknown. 7-8 colpi.

Agyneia bacciformes (Linn.) A. de Jussieu Breynia subtype; oblate.

P = E = P:E = v. Leeuwen-Reynvaan 1978 [U] 27,5 n 32,5 /j. 0,85. transversales Always two colpi present. Golpi 5-6. Costae colpi. Sauropus androgynis (Linn.) Merrill Breynia subtype; oblate spheroidal.

Doctors v. Leeuwen, Depok 7-5-’11 P = 25,5 iu E = 28 P:E = 0,90. [U] 8-9 colpi.

Breyniopsis subtype

Pollen grains subprolate.

Tectate; not reticulate.

The pollen grains of Breyniopsis are related to the pollen grains of Breynia by the number of colpi and the double circular colpi trans- versales. The and different. shape structure are, however, quite

Breyniopsis pierrei Beille Breyniopsis subtype; subprolate.

Poilane 19777 [P] PI. V, 7 P = 32,5 n E 28,5 n P:E = 1,14. transversales Always two colpi per colpus. 6-7 colpi. Costae colpi.

Glochidion type

Stephanocolporate (4); spheroidal - prolate spheroidal. transversalis circular Colpus or slightly elliptical; costae.

Colpi narrow.

or lumina 1-2 Intectate tectate; reticulate; p.

In the Glochidion is related many morphological respects type closely to the Breynia type, as Erdtman (1952) and Webster (1956) have stated. The pollen grains lack, however, the typical double colpus

transversalis. It is also possible to place the type in the Antidesma configuration. Its single circular, sometimes broad elliptic endexine

and in aperture the distinct reticulum are characters favour of a

place in the Securinega type (p. 25).

sericeum Hooker Glochidion P = E Glochidion (Blume) J. U. type; spheroidal. =

Brink P.A.I. = Bakhuizen v. d. 1886 [U] 24 n. Colpi narrow. 0,3-0,4.

PI. V, 8 Lumina 1-2 /<• Intectate.

Glochidion concolor Muell. Arg. Glochidion type. Yuncker 15648 [U] Glochidion littorale Blume Glochidion type.

Bakhuizen v. d. Brink 3182 [U] Glochidion obscurum (Willd.) Blume Glochidion type. Buysman 295 [U] Glochidion ramiflorum R. et G. Forster Glochidion type. Yuncker 15717 [U] Glochidion Glochidion superbum Baillon type. Dumas 1507 [U] 40 W. PUNT

Glochidion spec. Glochidion type. Teysman 4411 [U] Arachnodes Gagnep. chevalieri Glochidion type; prolate spheroidal. 31755 PI. 1 P = P:E = Fleury [P] VI, 25,5 n 1,06.

P.A.I. > 0,5. Tectate; intra-reticu- culate. Colpus transversalis slightly elliptical.

Aristogeitonia configuration

Stephanocolpate, stephanocolporate, stephanoporate, periporate or inapertu-

rate. The pollen grains are spheroidal or have a Polar axis shorter than the Equatorial axis. Tectate; usually echinate, sometimes psilate.

of the The types Aristogeitonia configuration form a closely related which is differentiatedfrom the other in group sharply configurations the Phyllanthoideae. They are easily recognised by the number of of the exine. have apertures and structure Most types echinate pollen and six small grains ca. apertures. The shape is spheroidal or oblate spheroidal to oblate. Taxonomic discussion

The includes of Aristogeitonia configuration a typical group genera which in several are, respects, different from other Phyllanthoideae. Mueller with too few of this (1866) was acquainted genera group to recognise it. Bentham (1880), however, enumerated, in the fourth of his all the of group Phyllantheae, genera the Aristogeitonia configu- ration then known. the of Bentham’s Only genus Bischofia group does not belong to the configuration. All the the genera belonging to configuration are found in one of the three into which Pax divides groups the Phyllanthoideae (Pax 1924). This includes his “Toxico- group subtribes Drypetinae, Petalostigmatinae, dendrinae” (= Hyaenanchinae), Dissiliarinae, Paivaeusinae and the tribus Caletieae of the Stenolobeae. Only Drypetes, Lingelsheimia and Heywoodia of the differ Drypetinae pollen-morphologically. The genera are small. The does than largest genus Longetia not come up to more

10 species. The male flower lacks an extra staminal disc. The flowers

while the always are apetal, number of stamens is seldom constant; there than six. In are mostly more the female flower the styles are best The of this undivided, at emarginate, but never incised. leaves

are often in whorls. Some group opposite or genera have, moreover, composite leaves.

Aristogeitonia type

Stephanocolpate, stephanocolporate or stephanoporate; oblate spherioidal - suboblate.

if small and Colpi, present, very short; costae colpi. Pori, if present, with costae.

Colpus transversalis, if present, with costae.

Tectate; echinate or psilate.

In the Aristogeitonia type the apertures are always situated in the pollen morphologyof the euphorbiaceae 41

The have the of equatorial plane. apertures can shape pori, colpi or

composite apertures, but they are always small.

Aristogeitonia subtype

Pollen grains echinate.

Aristogeitonia limoniifolia Prain Aristogeitonia subtype; stephanocolpate.

Herb. Kew. PI. 5 P = E = 35 P:E = VI, 30,5 [i 0,86.

Colpi ca. 4,5 /i long. Echinae ca. 2,5 jx. Oldfieldia africana Benth. Aristogeitonia subtype; stephanocolpate.

Small 621 P - E = 43 P:E = [K] 35,5 fi n 0,83.

Paivaeusa dactylophylla Welw. et Oliver Aristogeitonia subtype; stephanocolpate.

Shabana 9 P = 43 E = P:E = [K] ft 46,5 n 0,92. Piranhea trifoliata Baill. Aristogeitonia subtype; stephanoporate.

= 27 E = 32 P:E = Glaziou 14238 [K] PI. VI, 4 P fi n 0,85. Diam. 3 pori fx. Tetracoccus ilicifolius Coville et Gilmay Aristogeitonia subtype; stephanocolporate.

Mai. 2A. 1939 P = E = 40 P:E = Gilmay [L] 35,5 fi 0,91. Echinae Colpi 6-7. 3,5 /x. Hyaenanche globosa (Gaertn.) Lamb, et Aristogeitonia subtype; stephanocolporate.

Vahl P = 39 E = 46 P:E = ti n 0,85.

PI. 6 6-7. Echinae 2 Splitgerber [L] VI, Colpi ft. Mischodon zeylanicus Thwait. Aristogeitonia subtype; stephanocolpate.

Hort IX A. 125. 80883 P = 32 E = 36 P:E = 0,89. Bogor. [U] n n 5-6. Echinae Colpi 3,5 fi. Paragelonium perrieri Leandri Aristogeitonia subtype; stephanoporate.

= Perrier de la Bathie P = E = 35 P:E 1178 [P] 32 n v 0,92. Diam. 3 Echinae pori fi. 2,5-3,5 /x.

Petalostigma quadriloculare F. v. Mueller Aristogeitonia subtype; stephanoporate.

P = E = 32 P:E = Queensland [U] 28,5 n « 0,89. Pori 4-6; not always exactly in the diam. 3 Echinae equatorial plane; fi.

ca. 1 fi.

Longetia malayana (Benth.) Pax et Aristogeitonia subtype; stephanoporate.

K. Hoffmann P = 47 E = P:E = p 52 ft 0,90. Pori diam. 5 D’Alleizette, Penang 6421 [L] slightly ellpitical ca. fi.

Echinae up to 6,5 fi. Longetia carunculata (Baill.) Pax et Aristogeitonia subtype; stephanoporate. K. Hoffmann Pori 5 (-6). Mackee 4230 [L]

Longetia buxoides subtype

Pollen grains psilate.

Longetia buxoides Baillon Longetia buxoides subtype;stephanocolpate. P:E Nw. 6419 V = 22 E=27 = D’Alleizette, Caled. [L] n n 0,81. PI. VI, 7 Colpi (5-) 6 (-7); small and short

with thick costae. Dissiliaria tricornis Benth. longetia buxoides subtype; stephanoporate.

Brass 5755 PI. 9 P = 19 E = P;E = [L] VI, /x. 22,5 [x 0,85. diam. Pori 6; 2 ft.

Stachystemon type

Periporate or inaperturate; spheroidal or ellipsoid (with a longer and a shorter axis). Pori small; costae pori. Tectate; echinate.

In situated in the the Stachystemon type the apertures are never equatorial plane, but scattered over the surface. 42 W. PUNT

plate 1. Arachnodes 2. 3. vt. chevalieri; Phyllanthus nutans; Dendrophyllanthus ripicolus; 4. Piranhea trifoliata; 5. Aristogeitonia limoniifolia; 6. Hyaenanche globosa; 7. Longetia buxoides; 8. Phyllanthus acuminatus; 9. Dissiliaria tricornis. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 43

vermicularis Planch. Diam. 36 Stachystemon Stachystemon type. pc. Pritzel PI. Pori Echinae 270 [L] VII, 2 ca. 12; diam. pori 2,5 pc.

1,5 jU long.

Micrantheum ericoides. Desf. Stachystemon type. Longer axis 45 fi. Pori 347 Echinae Buysman 1873; [U] ca. 25; diam. 2 fi. usually in of three around the 3 groups pori; n long. Micrantheum Diam. 45 hexandrum J. D. Hook Stachystemon type. pc.

Tasmania [U] Pori small; more than 40.

Pseudanthus Sieb. ex Spreng. Diam. 20 pimeleoides Stachystemon type. pc.

Buysman 1890 [U] PI. VII, 7 Pori ca. 7; diam. 2 pc. Echinae 1 pc long. Diam 20 Pseudanthus nematophorus F. v. Muell. Stachystemon type. pc. Murchinson [U]

banksii Benth. Diam. 40 Neoroepera Stachystemon type. pc. Banks and Diam. Solander 1770 [K] pori 1,5 pc; ca. 30 pori. Echinae 2 pc long. Guile. Diam. Longetia gynotricha Stachystemon type. 34 pc.

Mackee 4191 Pori ca. 16. Echinae 2 [L] pc. Androstachys johnsonii Prain Stachystemon type. 3-8-1917 PI. axis 46 Shorter axis 40 Pole-Evans, [K] VII, 2 Longer fi. pc. 1 Echinae ca. pc.

Pollen types not placed in one of the above configurations

Some types cannot readily be placed in one of the discussed con-

figurations. Since most types have only one representative they and in are discussed separately not put any configuration.

Phyllanthus acuminatus type

Tricolporate (colpi diorate); spheroidal. Colpi transversales (two in each colpus) circular; costae. Colpi short.

Intectate; pilate. Pila ordinate arranged but not in a reticulum.

The of in the is also character presence two ora colpi an important The of the of the Breynia type (p. 38). structure exine, however, is quite different. Its remaining characters cannot be compared with other any configuration.

Phyllanthus acuminatus Vahl Phyllanthus acuminatus type.

= Hostman 413 [U] PI. VI, 8 P E = 27 n. P.A.I. = 0,5.

Bischofia type

Tricolporate; spheroidal, P:E is 1. Colpus transversalis small; costae. Edges of the costae transversales rounded

at the ends.

Colpi narrow and long; no costae colpi. Tectate; psilate. Columellae short.

This type should be best placed in the Antidesma configuration but differs from other in this its E types configuration by shape (P: = 1) columellae and the absence of costae colpi. The are moreover very short. 44 W. PUNT

Taxonomic discussion

Bentham (1880) discussed Bischofia together with Oldfieldia and Piranhea because of their digitately compound leaves. Pax and K.

Hoffmann the in subtribe. (1931) thought it better to put genus apart a similar As the pollen grains are certainly not to those of Oldfieldia and

Piranhea and moreover difficult in other to place any configuration, maintain it seems right to the separate subtribe.

Bischofia javanica Blume Bischofia type. Hohenacker 1573 = = = [U] PI. VII, 5 P E 25 ju. P:E ca. 1,

m:e < 0,5. P.A.I. = 0,2.

Putranjiva type

Tricolporate; spheroidal. P:E is 1. Colpus transversalis large; costae.

Colpi narrow; costae colpi. Tectate;psilate. Exine thick. Columellae short but endexine and tectum thick.

The Putranjiva type has some resemblances with the Dicoelia type - ... is transversalis (p. 28). There a large colpus with costae, and also

costae colpi. The type differs, however, by its shape (P: E =1) and the remarkably thick endexine.

In a specimen of Putranjiva (Stocks, India), examined by Erdtman

(1952), the pollen grains are subprolate, reticulate. The specimens Reorders 2156 and Broadway 9249 differ considerably from that

description. The typical character of the thick exine is not mentioned

by Erdtman and was probably not present in his pollen grains.

Taxonomic discussion

In the system of Pax and K. Hoffmann (1931) Putranjiva is found in the subtribe Glochidiinae. The is in genus put relatiosnhip with and Breynia Glochidion. Bentham (1880) gives it a place next to It of Drypetes. must be admitted, that the pollen grains Putranjiva are far more similar to those of Drypetes than to the Breynia type.

Wall. P == E = 40 Putranjiva roxburghii Putranjiva type. fi.

Koorders 2156/3 [U] P:E = ca. 1. m:e<0,5. 3 Braodway 9249 [U] PI. VII, P.A.I. = 0,3. Exine thick (4 fi).

Hymenocardia type

Triporate (-diporate); oblate. Costae pori. Tectate; psilate. Columellae short.

The type differs completely from all the other pollen grains in the Phyllanthoideae.

Taxonomic discussion

On account of its catkin-like male inflorescenses Pax and K.

Hoffmann (1931) placed Hymenocardia in the Antidesminae. The character of the is the two-cocced most striking genus compressed fruit with lateral differs from the wings. Hymenocardia other genera in

the Antidesminae in some characters: POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 45

platevh. I. Androstachysjohnsonii; 2. Stachystemon vermicularis; 3. Putranjiva roxburghii; 4. Martretia quadricornis; 5. Bischofia javanica; 6. Hymenocardia ulmoides; 7. Pseudanthus pimeleoides. 46 w. PUNT

1. in Disc wanting male as well as in female flowers.

2. The styles are long and undivided.

Hymenocardia ulmoides Oliv. Hymenocardia type.

Koechlin PI. 6 P = 19 E = = 2371 [U] VII, fi 22,5 n P:E 0,85. Tul. Hymenocardia acida Hymenocardia type.

P E = 31 P:E = Bequaert 7142 (BR) = 28,5 /j fi 0,92. Diam. 3 Duvigneaud 2422 (BRLU) pori fi.

Martretia type

Tricolporate; oblate spheroidal. Colpus transversalis; costae. Edges of the costae transversales rounded at the ends. Atrium present.

Colpi narrow; no costae colpi present. Tectate; psilate.

of The pollen grains the Martretia type are oblate spheroidal but do not have any other character in common with the Amanoa or Aristogeitonia configuration. The colpus transversalis has rounded ends.

This character is present in some types of the Antidesma configuration. and of the The oblate shape absence costae colpi keeps Martretia type out of the Antidesma configuration. A typical character is the atrium, which is found in other not any type.

Taxonomic discussion

Martretia has In this only one species. many respects species is related to the Antidesminae in its There (e.g. inflorescense). are, however, some differences.

1. in male No disc is present the flower nor in the female one.

The seeds with caruncula. No other in 2. are provided a genus the Antidesminae has carunculate seeds.

3. The in the whole with false in only genus family a partition the fruits (Pax and K. Hoffmann, 1922).

Martretia quadricornis Beille Martretia type.

Adames PI. P = E = = 251 [K] VII, 4 28,5 n 31 n P;E 0,92.

= — P.A.I. m:e 0,3 0,4. = 0,25.

Taxonomic comment on the Phyllanthoideae

The can be divided into three of Phyllanthoideae groups pollen types. These with the groups, broadly outlined, agree three groups Pax

(1924) could already distinguish on other grounds, though without nominating them. The first for the subtribes Antidesmineae group, to which, instance, and Phyllanthinae belong, has pollen grains which mostly have a prolate shape and distinct costae transversales (Antidesma configuration, The second has which reticulate p. 20). group pollen grains are mostly have oblate Amanoa and generally an shape (, configuration, p. 32). The subtribes this Amanoinae, Sarropodinae, etc., belong to group. The third those that be found group comprises genera are to in the Aristogeitonia configuration (p. 40). POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 47

For the Phyllanthoideae (Pax and K. Hoffmann, 1931) composed a differentiated of subtribes. This highly system many system, however, leaves much to be desired. Some subtribes (e.g. Glochidiinae) comprise which do show with each genera decidedly not any relationship other. On the other subtribes resemble contrary, genera in different

each other so much, that it would seem desirable to unite them (Wielandiinae with Amanoinae and Pseudolachnostylidinae). In the Phyllanthoideae pollen morphology is obviously exceedingly

useful to arrive at a natural classification.

b. Crotonoideae

Croton configuration

Croton-pattern present. Structure elements on the tectum are usually clavae

but can also be echinae, baculae etc. Sometimes the structure elements are

located on ridges (e.g. Croton matourensis, Manihot saxicola). Tectate.

The Croton configuration includes all pollen grains with a croton- In the found pattern. the Euphorbiaceae croton-pattern is only in the the Erdtman outside the subfamily of Crotonoideae. (1952) states, that,

Euphorbiaceae, pollen grains with a croton-pattern have been found in the Buxaceae and Thymelaeaceae. Most pollen grains with a croton-pattern belong to the Crotontype. Hevea less The Manihot type, Klaineanthus type and type occur commonly.

Taxonomic discussion

In the of the Crotonoideae a number of subfamily great genera possess pollen grains with a croton-pattern. In Pax and K. the Hoffmann’s system (1931) these genera occur in following tribes: Grotoneae, Ghrozophoreae, Joannesieae, Cluytieae, Manihoteae, Celonieae and Ricinocarpeae. Further also Neoboutonia

as the only genus out ofthe Acalypheae. It follows from this enumera-

that the to be found in tion, genera possessing a croton-pattern are widely divergent groupings. In classifying the Crotonoideaemost authors considered the bursting of the male be factor open calyx to a of primary importance for the Thus Mueller and Pax and K.Hoff- arranging genera. (1866)

mann arrived in which with obvious at a classification, genera an and Micrandra relationship are kept widely apart, e.g. Joannesia (Baldwin et Schultes 1947; Schultes 1955). Bentham (1880) stated that within the Croton the male both already genus calyx opens valvate and in imbricate, which is why, his system, this character

a less In Bentham’s the with plays important part. system genera a close be in his croton-pattern are placed together. They are to found subtribes Jatrophineae, Eucrotoninae and Ghrozophorinae.

In all the taxa that it is comparing possess a croton-pattern seen that several characters correlate with this pollen character. With

hardly an exception the male and the female flower contain a disc, ovarium rudiment is absent. A less while an constant but striking 48 W. PUNT character is the of in Genera which presence petals many genera. form an exception to these characters are: disc in both Sagotia. The is wanting sexes. The genus, however, is related to Dodecastigma, Sandwithia and Garcia (Croizat 1948), which, on the other hand, have a disc. This Australian has disc in both either. There Bertya. genus no sexes is, however, a distinct relation to two other Australian genera, viz. and which have disc. Beyeria Ricinocarpos, certainly a

Tritaxis has no disc in the female flower.

Adenocline and Tetrorchidium have no disc in the male flower.

The Pantadenia and described genera Oligoceras, by Gagnepain, were said to possess an ovarium rudiment in their male flowers. Pantadenia does have little conical in the ofits a projection centre receptaculum, but whether this projection represents an ovarium rudiment is not certain. in its male column Oligoceras possesses, flower, a which, according to a drawing by Gagnepain in the Flore General de In ITndochine (1926), was said to be an ovarium rudiment. studying the material in the author that the type Paris, however, concluded, the The column is drawing gives an erroneous picture of reality. not bottle-shaped but cylindrical. The five stamens are not placed at the foot of the but with it little column, are grown together at a distance of the base. The projections which stand at the end of the column in and which, the drawing, look like stigmas, are three staminodies. These staminodies even contain rudimentary pollen sacs.

Therefore there are two whorls of stamens, the topmost of which is sterile.

A more or less distinct ovarium rudiment is found in: Klaineanthus, Cladogelonium, Micrandra and Endospermum, which all belong

the to Klaineanthus type.

Genera not possessing a corolla are: Neoboutonia, Benoistia, Elaterio- spermum, Baliospermum, Eremocarpus, Micrandra (Cunuria), Hevea, Bertya, and has Beyeria, Adenocline Tetrorchidium. Suregada mostly no corolla (Leonard 1958).

is the Less The type occuring most frequently Croton type. common are the Manihot type, the Klaineanthus type, Hevea type and Adenocline type.

Croton type

Inaperturate; spheroidal or ellipsoid i.e. with a longer and a shorter axis. Tectate; endexine thin. Croton-pattern. echinate. Clavate or

Croton has and The type no apertures the shape is fairly uniform. There be and shorter but the may a longer a axis, usually pollen grains

are spheroidal. The structure elements have more variations. The

differences in these elements and the lumina enclosed by the elements, and transitions however, are slight many exist, so that it seems better omit the formation of to groups (subtypes). of Thepollen grains Sagotia racemosa show two shapes. The specimens and For. Y. Mexia Woob Herb, are echinate, while the specimen Dep. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 49

plate vm. 1. Croton cuneatus; 2. Croton matourensis (x 800). 50 w. PUNT

Further examination will be is clavate. necessary to ascertain whether these other two shapes of Sagotia racemosa can be distinguished by characters besides.

According to Schultes (1952) Cunuria cannot be distinguished from The of Micrandra. pollen grains the Cunuria specimen Ducke 1087 the In another belong to Croton type, and not to the Micrandra type. Cunuria specimen (Ducke 24874) Erdtman (1952) described the pollen Schultes grains as being 5-colporate. According to (1952) the two Ducke specimens both belong to Cunuria spruceana var. bracteosa. Micrandra siphonoides and Micrandra brownsbergensis stand pollen-

morphologically between the two specimens of Cunuria spruceana var.

bracteosa.

Klotzsch Croton cuneatus Croton type. P. 1113 PI. 1 Diam. axis 75 diam. J. et Florschutz [U] VIII, longer /*. Clavate;

clavae 3,5 fi. Clavae on ridges. Millsp. Croton Croton bahamensis type. Diam. 55 /x.

Brace 4064 D. cl. [U] 2,8 fi. Diam. Croton longiradiatus Lanj. Croton type. 75 fi.

B.W. 6711 D. cl. Clavae on [U] 2,2 /x. distinctly ridges. Croton hirtus L’Heritier Croton type. Versteeg 504 [U] Aubl. Croton Croton matourensis type.

B. 5050 [U] PI. VIII, 2 Clavae acuminate; distinctly on ridges. Diam. 115 D. cl. fi. 6,5 fx. Croton pullei Lanj. Croton type. 654 Diam. 115 D. Rombouts [U] cl. 6,5 fi. Clavae distinctly on ridges. Baillon Diam. 120 Julocroton triqueter Croton type. /x. 6016 D. Hassler [U] cl. 3,2 fx. Didrichs Diam. Julocroton argenteus (Linn.) Croton type. 120 /x. Schulz 1225 D. cl. C. L. [U] 3,2 fx. WlIXD. Croton Diam. 60 Crotonopsis elliptica type. fx. Delzie 7066 D. cl. Demaree [U] 1,5 fx. Benth. Croton Diam. 60 Eremocarpus setigerus (Hook.) type. /x. S. Rose D. cl. L. 41457 [U] 2 /x.

Grossera Pax Croton Diam. 48 major type. fx. Zenker D. cl. 469 [U] 1,8 /x. 45 Holstia tenuifolia Pax Croton type. Diam. fx. 3480 Drummond et Hemsley [K] D. cl. 2 fx.

Cyrtogonone argentea (Pax) Prain Croton type. Diam. 60 /x.

Zenker D. cl. 561 [U] 3,5 fx. Pax Diam. Crotonogyne preussii Croton type. 60 /x. 4666 D. cl. 2 Zenker [L] _ /x. Crotonogyne parvifolia Prain Croton type. Diam. 50 fx. 6845 D. cl. D’AlTeizette [L] 2,8 /(. Muell. Arg. Diam. 60 Manniophyton fulvum Croton type. /t. 1404 D. Zenker [L] cl. 3,5 /x. Aleurites Willd. Croton Diam. 70 moluccana (Linn.) type. fx. D. cl. Bunnesmeyer 8060 [U] 2,0 /x. tonkinensis Gagnep. Croton Diam. 65 Deutzianthus type. /x. Balansa 3149 D. cl. [P] 2,0 /x. Gagnep. Croton Diam. 50 Oligoceras eberhardtii type. /(. Eberhardt D. cl. [P] 1,8 fx. Diam. Alphandia furfuracea Baillon Croton type. 40 /x. D. cl. Balansa 3439 [P] 2,0 /.i. Croton Diam. 60 Garcia nutans Vahl type. /(. Lundell 12248 D. cl. [U] 2,0 fx. 51 POLLEN MORPHOLOGY OF THE EUPHORBIACEAE

Joannesia princeps Velloso Croton type. Diam. 70 ft.

T. W. Brown 35 D. cl. Clavae on [K] 3,0 ft. ridges. Diam. 40 Neoboutonia macrocalyx Pax Croton type. ft. D. cl. Stolz 2043 [U] 1,5 fi. Pantadenia adenanthera Croton Diam. 45 Gagnep. type. ft.

British Museum D. cl. 1,0 fi. Diam. 40 Baloghia lucida Endlicher Croton type. fi. River D. cl. Beckler, Hastings [U] 1,0 ft. Croton Diam. 65 Ostodes paniculata Blume type. ft. Griffith 4790 D. cl. [U] 3,5 ft. Ostodespendulus (Hassk.) Meeuse et Croton type. Diam. 53 ft.

DIPT RFRT D. cl. A 2,8 ft. Sandakan For. Dep. A. 2964 [U] Croton Diam. 50 Codiaeum variegatum (Linn.) Blume type. ft. material from D. cl. Fresh greenhouse at 2 ft. Utrecht. PI. IX, 3 50 Codiaeum stellingianum Ware. Croton type. Diam. ft. 1567 D. Docters v. Leeuwen _[U] cl. 2,0 ft. Croton Diam. 60 Fontainea pancheri (Baillon) Heckel type. ft. 6474 D. cl. D’Alleizette [L] 2,8 ft. Croton Diam. 80 Dimorphocalyx murina Elmer type. ft. cl. Elmer 12773 [U] D. 3,5 ft. Diam. 35 Benoistia perrieri Leandri Croton type. ft. 1905 D. cl. D’Alleizette Madag. Dec. [L] 1,8 ft. Diam. 45 Tritaxis gaudichaudi Baill. Croton type. ft. Echinate. Diam. Clemens 4351 [U] ech. 1,8 ft. Croton Diam. 60 Strophioblachia fimbricalyx Boerl. type. ft. F. 43 D. cl. Sort. Bog. VIS [U] 1,8 ft. Baill. Croton Diam. 45 Blachia umbellata (Willd.) type. ft. D’Alleizette Austr. Nov. 1907 [I.] D. cl. 1,8 ft. Croton Diam. 50 Sagotia racemosa Baillon type. ft. For. Dep. 7443 [U] D. cl. 2,0. Clavae sharp pointed.

Echinate. Diam. 40 D. ech. Mexia 6050 [U] ft. 1,8 ft. Wood Herb. 311 [U] Linn. Diam. 95 Jatropha multifida Croton type. ft. Groll-Meyer, St. Eustatius [U] D. cl. 4,0 ft. Clavae on ridges. multifida Jatropha integerrima Jacq,. Croton type. Idem. Jatropha

Docters v. Leeuwen 19-7-1950 [U] Croton 50 Mildbraedia paniculata Pax type. Diam. ft. 3004 D. cl. Leeuwenberg [U] 2,5 ft. Crises. Croton Diam. 45 Acidocroton adelioides type. ft.

Ekman 16896 D. cl. 1,5 [K] ft. Diam. 50 Pausandra densiflora Lanj. Croton type. ft. D. cl. Krukoff 5464 [U] 2,0 ft. Diam. 75 Pausandra morisiana (Casar.) Radlk. Croton type. ft. Kuhlmann 16594 D. cl. Ducke et [U] 3,5 ft. Croton Diam. 48 Givotia rottleriformis Griffith type. ft. Wight 2638 [L] D. cl. 2,8 ft, Pierre Diam. Ricinodendron heudelotii (Baill.) Croton type. 50 ft.

D. cl. 2,5 ft. Zenker 487 [U] Diam. Elateriospermum tapos Blume Croton type. 70 ft.

cl. Clavae on Hort. Bog. IX. A. 129 [U] D. 3,2 ft. ridges. Diam. 43 Baliospermum motanum (WlLLD.) MUELL. Croton type. ft. D. cl. 1,5 ft. Bengal, J. D. Hooker [U] Croton Diam. 75 Cavacoa aurea (Cavaco) Leonard type. ft. cl. de Winter 2109b [K] D. 2,0 ft. Anomalocalyx uleanus (Pax et K. Hoffm.) Croton type. Diam. 55 ft. OlTPIfP D. cl. 3,2 ft. Ducke 23518 [U] 52 W. PUNT

plate rx. 1. Manihot saxicola (X 600); 2. Tannodia cordifolia; 3. Codiaeum variegatum. POLLEN MORPHOLOGY OF THE EUPHORBLAGEAE 53

Croton Diam. 55 Sandwithia guyanensis Lanj. type. fi. 2731 For. Dep. [U] D. cl. 3,5 fi. Ducke Diam. 80 Dodecastigma amazonicum Croton type. ft. Ducke 23543 D. cl. [U] 4,5 ft. Baillon Diam. Cunuria spruceana var. bracteosa Croton type. 50 fi. R. E. Schultes D. cl. (Ducke) 1,8 fi. Ducke 1087 [K] cataractarum R. E. Schultes Croton Diam. 70 Vaupesia type. fi. Schultes 14006 D. cl. [K] 3,0 ft. Diam. Ricinocarpos pinifolius Desf. Croton type. 60 fi. Austr. felix D. [U] cl. 1,8 ft. Baill. Diam. 43 Beyeria leschenaultii (Decand.) Croton type. fi. D. cl. Austr. felix [U] 1,5 u. Clavae sharp pointed. Planch. Croton Diam. 55 Bertya gummifera type. fi. Johnson et Constable 16024 [U] Croton-pattern indistinct. Domohinea L£andri Diam. 50 perrieri Croton type. ft. D’Alleizette 6479 Dec. 1905 PI. 1 [L] X, Croton-pattern on ridges. Echinate;

diam. ech. 1,5 fi. Tannodia Baillon Croton Diam. 35 cordifolia type. fi. Comoren diam. D’Alleizette, 6484 [L] Echinate; ech. 1-1,5 fi. PI. IX, 2

Manihot type

Periporate; spheroidal. Pori large, borders indistinct. Tectate. Croton-pattern.

The type is closely related to the Croton type. The pollen grains,

however, have large apertures with indistinct rims. The number of pori varies in the different species.

Taxonomic discussion

Croizat According to (1943b) Cnidiscolus does not have a calyx but corolla. This is also the with Manihot. In definite a case a very

sense Cnidiscolus connects Jatropha, sensu strictu, with Manihot. Both the sorts of Cnidiscolus examined had pollen grains of the Manihot

in closer type, sothat at least this respect they are related to Manihot

than to Jatropha. The pollen-morphological similarity between Manihot and Suregada

is probably accidental and has to be considered a parallel development.

Manihot saxicola Lanj. Manihot type. Proefst. Buitenz. 922 Boom 8 Diam. 160 [U] fi. Croton-pattern on a PI. IX, 1 distinct reticulum.

Pori ca. 25. Diam. clavae 6,8 fi. Manihot esculenta Crantz Manihot type. Rombouts 757 [U] Idem Manihot saxicola. 2780 Pori 25. B.W. [U] ca. Arthur Manihot Cnidiscolus urens (Linn.) type. Diam. 75 fi. 4829 D. cl. Pori 3^1. Boldingh [U] 2,5 fi. Cnidiscolus stimulosus (Michaux) Gray Manihot type. Pori ca. 6. Killip 31636 [U]

Baill. Manihot Diam. 40 Suregada glomerulata (Blume) type. ft. Griffith D. cl. Pori 4772 [U] 2,5 fi. 3-5. Croizat Manihot 45 Suregada subglomerulata (Elmer) type. Diam. /i. Elmer 12967 [U] Pori 5-6. 54 W. PUNT

Klaineanthus type

Tricolpate; oblate spheroidal to oblate.

wide Colpi or narrow; no operculum present. Tectate; croton-pattern.

related the Croton The Klaineanthus type, too, is closely to type and

the Manihot type. Pollen grains of this type have colpi without an operculum. The colpus membrane is frequently ruptured.

Klaineanthus subtype

Boarders of colpi distinct. Glavate.

The the The rims of colpi of this subtype are distinct. colpus membrane is frequently totally ruptured. In Cladogelonium the colpus but membrane is not ruptured granulate. Sometimes a rudiment of

the colpus membrane remains at the outer ends of the colpi.

Klaineanthus gaboniae Pierre ex Prain Klaineanthus subtype; suboblate.

Zenker 583 PL 3 P = £ = P:E [U] X, 29,5 /i 37/1 = 0,80.

Colpi wide. P.A.I. = 0,4.

Diam. clavae 1,8 /t. Cladogelonium madagascariense L6andri Klaineanthus subtype; spheroidal.

= Perrier de la Bathie 9696 PI. 4 P = E = P:E [P] X, 30/i 30,5 fx 0,98. Colpus membrane granulate.

P.A.I. = 0,4. Endospermum moluccanum (Thysm. et Klaineanthus subtype; suboblate.

Beccari P = E = P:E = Binnend.) 33,5 n 44,5 /i 0,80.

Kornasse 462 [U] Colpus membrane absent. P.A.I. = Diam. clavae 0,4. 1,8 /i. Glycydendron amazonicum Ducke Klaineanthus subtype; oblate.

Ducke P = E P:E = 17108 [U] 29 /« =41,5/t 0,69.

Colpus membrane absent. P.A.I. =

clavae O, Diam. 1,5 fi. Micrandra brownsbergensis Lanj. Klaineanthus subtype.

v. Emden 9 [U] Colpus membrane absent. Micrandra siphonioides Benth. Klaineanthus subtype.

Lopez 9625 [U] PI. X, 5 P = 41,5 fi E = 46 /< P:E = 0,92.

P. = 0,3. Croton-pattern indis- tinct. Clavae candelabrum-shaped, in-ordinate arranged. Adenocline subtype

Borders of the colpi not sharply cut but irrigularly ruptured.

Baculate. Baculae small and crowded.

The baculae on the tectum are small and crowded. With low

magnification it is not directly obvious that the structure elements

form a croton-pattern and not a reticulum.

Taxonomic discussion

The Adenocline in the of Seidelia and genus was placed vicinity Leidesia in the Acalypheae by Bentham (1880). Pax and K. Hoffmann could find the relation and the in (1931) not same put genus a separate subtribe in the tribe Gelonieae. This tribe also comprises the genus Klaineanthus. The different in other two genera are, however, quite respects. POLLEN MORPHOLOGY OF THe'eUPHORBIACEAE 55

plate x. 1. Domohinea perrieri; 2. Suregada subglomerulata; 3. Klaineanthus gaboniae; 4. Cladogelonium madagascariense; 5. Micrandra siphonioides; 6. Hevea brasiliensis. 56 W. PUNT

Adenocline acuta (Thunb.) Baiix. Adenocline subtype; oblate spheroidal.

A. mercurialis P = 36 E = [= Turcz.] /a 37,5 n P:E = 0,96. 613 PI. P.A.I. Lanjouw [U] XI, 2 = 0,4.

Hevea type

Tricolpate; oblate spheroidal.

Colpi wide; operculum present.

Tectate; baculate. The baculae are so small and crowded, that the structure is hardly recognised as a croton-pattern.

As in the Adenocline subtype the baculae of the Hevea type are small in diameter and crowded. With low magnification the structure ele- ments seems to form a reticulum, but with high magnification the arrangement of the structure elements is clearly a croton-pattern.

The operculum distinguishes this type from the Klaineanthus type.

Hevea brasiliensis (Willd. ex A. Jussieu) Hevea type; oblate spheroidal.

Mueix. Arc. P = E = 35 P:E 33,5 fi n = 0,96. Schultes 8050 [U] P.A.I. = 0,3. B.W. 752 [U] PI. X, 6 Hevea Aublet Hevea guianensis type.

B.W. 41 P = E 38 P:E = fU] 35 i* = n 0,95. Krukoff 5800 [U]

Tetrorchidium type

Tricolporate; oblate spheroidal to prolate spheroidal. Colpus transversalis exceptionally broad and elongated. No costae present. rims Colpi narrow; irregular.

Intectate; pilate. Pila coarse.

The Tetrorchidium type is tricolporate and differs by this character from the tricolpate Klaineanthus type. The extremely broad colpus transversalis is elongated to a colpus transversalis equatorialis. The of tectum this type is indistinct and the croton-pattern is not clear in all the pollen grains. In Tetrorchidium didymostemon the structure elements on the tectum are certainly not arranged in a croton-pattern. Tetrorchidium rubrivenium shows the croton-pattern more readily. Although the most important characters of the Croton configuration the are not always present, structure of the pollen grains and the shape of the much like those in the Klaineanthus colpi are very type. The

_ author therefore Tetrorchidium in the prefers to keep the type vicinity of the Klaineanthus type.

Taxonomic discussion

Pax and K. Hoffmann (1931) referred Tetrorchidium into the sub- v , tribe Tetrorchidiinae. This subtribe was placed in the tribe Gelonieae, to which also Klaineanthus belongs. Although in habit and character Adenocline and Tetrorchidium differ widely, the flowers have some characters in common:

1. In the male flowers disc and ovarium rudiment are absent. 2. In the female flowers the disc consists of three free glands. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 57

Tetrorchidium rubrivenium Poepp. Tetrorchidium type; oblate spheroidal.

Harris and Britton 10746 = P 36 £ = = [K] n 40/1 P:E 0,90. P.A.I. Bacculate-verruca = 0,35. te. Pax Tetrorchidium didymostemon (Baillon) Tetrorchidium type; prolate spheroidal.

et K. Hoffmann P = 28 /i E = 27 n P:E = 1,04.

Zenker 4590 [L] PI. XI, 3 P.A.I. = 0,35.

Cnesmosa configuration

Inaperturate; no croton-pattern present.

Tectate or intectate.

Like the Croton type the Cnesmosa configuration is inaperturate, but a croton-pattern is always absent.

Cnesmosa type

Pollen i.e. Inaperturate. grains ellipsoid, with a longer and a shorter axis, Tectate; psilate. No reticulum.

of The pollen grains this type are closely related to the Tragia fallax type and the Platygyne type. In the Cnesmosa type the pollen grains

are tectate.

Taxonomic discussion

The to this are related and genera belonging type closely not easy

to separate. Croizat (1941a) discussed the relationship between some Plukenetiinae genera of the and came to the following conclusions:

1. Cenesmon Gagnepain cannot be separated from Cnesmosa Blume.

2. Megistostigma malaccense, reduced to Sphaerostylis by Pax and K. is the taxonomic of the Hoffmann, type genus Megistostigma, which is congeneric with Clavistylus J. J. Smith. 3. Pax and K. Hoffmann should be treated Tragiella as a synonym of Sphaerostylis, ofwhich S. tulasneana is the taxonomic type (p. 63).

full The pollen-morphological results are in agreement with the statements of Croizat.

Cnesmosa javanica Blume Cnesmosa type; ellipsoid. Borneo axis 55 Elmer, 20663 [U] Longer p. Java 1855 [L] Megistostigmapeltatus (J.J. Smith) Croizat Cnesmosai type; ellipsoid.

Steenis 1235 PI. 6 axis 56 shorter axis 53 v. [L] XI, Longer fi ; p. Megistostigma malaccense J. D. Hook. Cnesmosa type; ellipsoid. Sinclair 40242 PI. 4 axis 42 shorter axis 37 [U] XI, Longer //; /i. in Columellae groups.

Acidoton urens Swartz Cnesmosa type; ellipsoid.

Hooker axis shorter axis Jamaica, [U] Longer 37,5 fi\ 35,5 ft.

Tragia fallax type

Pollen grains inaperturate; spheroidal or ellipsoid. Intectate, pilate. Pila not in reticulum. Endexine thin. a very

This type differs from the Cnesmosa type by its intectate structure. in The pila are not arranged a reticulum. 58 W. PUNT

Taxonomic discussion

The examined species belong to the section Bia of Tragia. Klotzsch and Baillon (1858) separated this section from Tragia. Pax and K. Hoffmann (1919a) also stated: “Die mannliche Bliite weckt den als ob eine all the Eindruck, es um eigene Gattung handelt’Mf species of the section Bia have the inaperturate pollen grains, it is perhaps better this section distinct to treat as a genus, although a great affinity

with Tragia cannot be denied.

Tragia fallax Muell. Arc. Tragia fallax e - ‘yp ; Klug 4207 [U] PI. XI, 5 Diam. 50 u. Pila 1,5 /J. Tragia sellowiana (Klotzsch) Muell. Tragia fallax type. Arc.

Smith 3558 Diam. 55 [U] /a.

Platygyne type

Inaperturate. Pollen grains ellipsoid. Tectate; intra-reticulate. Endexine with circular thickenings.

The Platygyne type is distinguished from the Cnesmosa type by its

distinct intra-reticulum. Small circular thickenings occur on the

These endexine. peculiar “costae” are distributed irregularly over the endexine and certainly not accompagnied by thinnings ofthe ektexine.

hexandra Muell. Arg. Platygyne (Jacq.) Platygyne type; ellipsoid. 346 Rutten-Pekelharing [U] PI. XI, 1 Longer axis 40 fx. Shorter axis 36 u. Lumina 2-3 fi.

Trigonostemon verrucosus type

Inaperturate; spheroidal or ellipsoid.

Tectate. Gemmate.

Trigonostemon verrucosus J. J. Smith Trigonostemon verrucosus type; spheroidal. axis Diam. 2 Longer 60 /(. gemmae jx. Cult. Hort. VIII. E-16 Bog. [U] Gemmae not in a croton-pattern. PI. 3 XII, Trigonostemon verrucosus type. Merrill Diam. 60 Diam. Trigonostemon fungii fi. gemmae 1,5-2 /i. Linsley Grishitt 1089 [BM]

redioides Trigonostemon type

Inaperturate; spheroidal to elliptical. Intectate; reticulate.

Both Trigonostemon types are inaperturate without a croton-pattern.

They belong for these reasons to the Cnesmosa configuration. with the The Trigonostemon verrucosa type gemmate structure its elements on tectum is perhaps related to the Croton type (p. 48). The in gemmaeare, however, certainly not arranged a croton-pattern. the and lack of the Except for shape apertures Trigonostemon redioides does have character in with the Croton type not any common con- figuration. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 59

plate xi. 1. Platygyne hexandra; 2. Adenocline mercurialis; 3. Tetrorchidium didymostemon; 4. Megistostigma malaccense; 5. Tragia fallax; 6. Megistostigma peltatus. 60 w. PUNT

Taxonomic discussion

the of Although pollen grains the Trigonostemon type are not provided _ _

— with a the has with croton-pattern, genus Trigonostemon great affinity in the genera Croton configuration. Corresponding characters are:

1. In the male as well in the female flowers a disc is found and an

ovarium rudiment is absent.

2. Sepals are present.

Trigonostemon redioides (Kurz) Craib Trigonostemon redioides type. Longer axis

Coudre PI. 5 34 Shorter axis 30 Lumina 1 [BM] XII, fi. ft. -2 ft.

Trigonostemon longifolius Wall, ex Baillon Trigonostemon redioides type- Achmad Diam. 55 Lumina 3-5 142 [U] ft. fi.

Prosartema gaudichaudii Gagnep. Trigonostemon redioides type. Poilane 10446 38 axis [K] Longer axis p\ snorter 35 fi. Lumina ca. 2 fi. Actephilopsis malayana Ridl. Trigonostemon redioides type-

2300 axis 45 Lumina Ridley [K] Longer fi. small, 1 ca. /i.

Dysopsis configuration

Inaperturate. Pollen grains quasi tricolpate, distinctly three-lobed.

Tectate; no croton-pattern present.

Dysopsis type

Inaperturate; quasi tricolpate; oblate spheroidal.

Tectate; psilate. Columellae fairly coarse.

The most striking character is found in the three-lobed shape of the pollen grains. The declination between the lobes is distinct, but there is the indication of not slightest any part of the exine being

weakened. According to the definition (see glossary) the pollen grains

are inaperturate.

Taxonomic discussion

Mueller (1866) as well as Pax and K. Hoffmann (1914, 1931) kept Dysopsis in close relationship with Leidesia and Seidelia. These latter African genera are, however, geographically far removed from The three the Andine genus Dysopsis. genera belong undoubtedly to the Acalypheae. The pollen grains of Dysopsis have little affinity with

those of Leidesia and Seidelia. Perhaps it should be better to separate in Dysopsis a different subtribe.

Dysopsis glechomoides(Rich.) Muell. Arg. Dysopsis . . „ . type. . ,

Lechler 956 6 P = 21 E = [K] PI. XII, /i 22,5 fi P:E = 0,93.

Plukenetia configuration

Tricolpate or triporate. Shape of the pollen grains oblate spheroidal to oblate (rarely prolate spheroidal).

Apertures broad; costae absent.

membrane Colpus or porus ruptured. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 61

1. Plukenetia 3. plate xn. verrucosa; 2. Fragariopsis scandens; Trigonostemon verrucosus; 4. Plukenetia volubilis; 5. Trigonostemon redioides; 6. Dysopsis glechomoides. 62 W. PUNT

The types of the Plukenetia configuration have simple apertures. with the In contrast Chiropetalum configuration the apertures are In broad and have a ruptured colpus membrane. some species a small

piece of this membrane persists at the outer ends of the colpi.

Plukenetia type

Tricolpate; oblate spheroidal to oblate (rarely spheroidal or prolatespheroidal). ends Colpi broad; colpus membrane ruptured. At the outer of the apertures a small piece of the colpus membrane (i.e. endexine) persists. bordered The ruptured part is sometimes by a margo.

Tectate or intectate. Reticulate or not reticulate.

Pollen grains belonging to this type can have very different exine be while structures. They may intectate, tectate or tectum perforate, the columellae are inordinate arranged or form a reticulum. The

various subtypes are based on the structure patterns of the exine.

Taxonomic discussion

From the Plukenetia have been genus new genera separated by

j several authors. 1 ax and K. Hoffmann maintain this division ~ (1919a) of Plukenetia. Bentham (1880), however, has pointed out thatFragariop- sis and Romanoa differ only slightly from the typical Plukenetia species.

Other authors, too, see little difference. Uroizat (1941a): “JNo

characters are available to separate Pterococcus and Tetracarpidium

“ from Plukenetia Macbride (1951): Apodandra and Fragariopsis could readily be included in Plukenetia". Certainly the pollen grains

of the from Plu- above genera are not easily distinguished those of kenetia.

In South-America three tree-shaped, non-climbing genera are to

“ be found. Sandwith of them: Astrococcus and (1950) says Angostyles, three allied the Plukenetiinae”. Haematostemon are closely genera of

The pollen is indeed related. They all belong to thePlukenetia volubilis and Astrococcus and Haematoste- subtype possess a tectum perforatum.

mon have moreover a margo.

On account of the imbricate calyx Bentham and Pax and K. Hoffmannplaced Omphalea outside the Plukenetiinae. Croizat (1942a, his that the shows 1948), however, gives as opinion genus strong

affinity to the Plukenetiinae. The pollen of Omphalea also appears to resemble the Plukenetia volubilis subtype very closely.

Plukenetia volubilis subtype

Tectate; psilate. Sometimes the tectum is a tectum perforatum.

Plukenetia volubilis Linn. Plukenetia volubilis subtype; oblate.

153 PI. 4 P = 36 E = 56 P:E = Baker [U] XII, ft 0,64.

P.A.I. = 0,35. Plukenetia abutifolia (Ducke) Pax et Plukenetia volubilis subtype.

K. Hoffm. P = 50 E = 62 P;E = n n 0,80. Ducke 20619 [U] Tectum perforatum. Eleutherostigma lehmannianum Pax et Plukenetia volubilis subtype.

P = 37 E = P;E = K. Hoffm. fi 47,5 n 0,79.

Lehmann 5158 [K] PI. XIII, I P.A.I. = 0,35. 63 POLLEN MORPHOLOGY OF|THE EUPHORBIACEAE

Tetracarpidium conophorum (Muell. Arg.) Plukenetia volubilis subtype.

Pax K. Hoffm. P = E = 44 P;E = et 30,5 n n 0,69.

[= Plukenetiaconophorum Muell. Arg.] P.A.I. = 0,15 — 0,2. Margo. Mann 1739 [U] Versuchsanst. 9 [U] Pterococcus corniculatus (E. Smith) Pax et Plukenetia volubilis subtype.

K. Hoffm. P = = 44 P:E = 32 n E n 0,66. E. P.A.I. [= Plukenetia corniculatus Smith] = 0,2. Koorders 41720 B [U] Anabaenella tamnoides (Juts.) Pax et Plukenetia volubilis subtype.

K. Hoffm. P = 43 E = P:E = n 49,5 fi 0,87.

nom. illeg. [= Romanoa ] Trevisan P.A.I. = 0,2. Margo. =Plukenetia tamnoides (Juss.) Muell.

Lutz [U] Angostyles longifolia Benth. Plukenetia volubilis subtype.

Ducke 23528 P=45 E = 60 P:E = 0,75. [U] Ju /<

P.A.I. = 0,45. Tectum perforatum.

Astrococcus cornutus Benth. Plukenetia volubilis subtype.

PI. 3 P = E = 50 P:E = Spruce 2050 [K] XIII, 36,5 n n 0,73. P.A.I. = 0,4. Margo; tectum per-

foratum.

Haematostemon guianensis Sandwith Plukenetia volubilis subtype.

Fanshawe 6016 P = 29 P:E = [U] /j. E=40/r 0,74.

P.A.I. = 0,25. Margo; tectum per- foratum indistinct.

Omphalea diandra Linn. Plukenetia volubilis subtype.

Frees 1893 PI. 2 P = E = P;E = 0.59. (Krukoff) [U] XIII, 21,5 n 30,5 n

Lanjouw and Lindeman 3164 [U] P.A.I. = 0,3. Tragia capensis Thunb. Plukenetia volubilissubtype; spheroidal.

Hooker Herb. P = E [K] = 17 /a.

Plukenetia verrucosa subtype

Intectate (?); reticulate.

Plukenetia verrucosa Smith Plukenetia verrucosa subtype; suboblate.

B.W. 993 PI. 1 P = 28 E = 35 P:E = [U] XII, /x // 0,80.

P.A.I. = Lumina 0,3. 2-3 fi-

Apodandra buchtienii (Pax) Pax Plukenetia verrucosa subtype. [= Plukenetia buchtienii Pax] Krukoff 10753 [U]

Fragariopsis scandens St.-Hill. Plukenetia verrucosa subtype.

D’Alleizette 6594 PI. 2 P = E = P:E = [L] XII, 33,5 n 41,5 n 0,81.

P.A.I. = 0,45. Pax K. Hoffm. Plukanetia Tragia stolziana et verrucosa subtype.

Stolz 1775 [U] PI. XIII, 4 P=29/t E = 32 P:E = 0,90. Reticulum consisting of separate pila, lumina 1-2 (i. P.A.I. = 0,6.

Sphaerostylis natalensis (Sond.) Croizat Plukenetia verrucosa subtype. Someren P P:E v. 2409 [K] = 38,5 ti E=43/t = 0,89.

P.A.I. = Lumina 0,6. 1-2 /i. tulasneana Baill. Sphaerostylis Plukenetia verrucosa subtype.

Nossibe. Nov. P = 35 E = 44 P:E = D’Alleizette, 1906 [L] /« /I 0,84.

P.A.I. = Lumina 1-2 0,3. /i.

Tragia tristis subtype

Intectate; pilate. Pila not in a reticulum.

Tragia tristis Muell. Arg. Tragia tristis subtype.

Hassler 6645 PI. 5 P = 27 E = 40 P;E = [BM] XIII, n fi 0,68. P.A.I. = 0,3. 64 W. PUNT

plate xin. 1. Eleutherostigma lehmannianum; 2. Omphalea diandra; 3. Astrococcus cornutus; 4. Tragia stolziana; 5. Tragia tristis; 6. Pachystilidium hirsutum. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 65

Tragia geraniifolia Baill. Tragia tristis subtype.

= = Herter 1006 A. P” E = P:E [U] 31,5 /i 41,5 ti 0,76.

P.A.I. = Pila 1 0,3. ca. fi. Tragia volubilis Linn. Tragia tristis subtype. Focke 992 [U]

Tragia ramosa Torr. Tragia tristis subtype. Rogerson 4-6-1954 [U]

Pachystylidium type

Triporate; spheroidal.

Apertures are circular in shape and sunk down. The borders are indistinct. Tecta te; psilate.

has circular rims The Pachystilidium type apertures, of which the are indistinct. It is, however, not clear if the type belongs with the Plukenetia The ektexine is certainty to configuration. only very indistinctly weakened and it is therefore possible to call the type inaperturate. The endexine, however, is clearly thinned. In the

author’s opinion it is better to keep the type in thePlukenetia configura-

tion and not in the Cnesmosa configuration.

Pachystilidium hirsutum (Blume) Pax et Pachystylidium type. . ,

K. Hoffmann P = E = 29 fi. P.A.I. = 0,6-0,7. Elbert 3340 [L] PI. XIII, 6

Chiropetalum configuration

Tricolpate or stephanocolpate (4); shape variable. Colpi long. No costae colpi. Colpus membrane (endexine) persistent.

[Rarely tricolporate, but then pollen grains prolate in shape and anoperculum present.]

This configuration is distinguished from the Plukenetia configuration by the colpus membrane, which is never ruptured.

Taxonomic discussion

of The genera the Chiropetalum type, Ditaxis type and Argythamnia related. Mueller and type are closely (1866) Bentham united them in the Pax and one taxon, genus Argythamnia (except Leucocroton). K. Hoffmann the and (1912c, 1931) kept genera separated, according to pollen morphology this seems the right opinion.

Chiropetalum type

Tricolpate (or rarely tricolporate); spheroidal to prolate spehroidal. Colpi wide; operculum present; costae colpi absent. Tectate or intectate; finely reticulate. [Rarely colpus transversalis present.]

The Chiropetalum type and the Lasiocroton type are related by the of and its presence an operculum. Chiropetalum allies, however, are finely reticulate. From the Ekman 16425a sheet Erdtman (1952) described Leucocro-

ton flavicans as colpate. The Ekman sheet 12343 as examined by the 66 w. PUNT author from the Kew herbarium has tricolporate pollen grains. These be in pollen grains should placed a different configuration, although other characters (e.g. the operculum and fine reticulum) are consistent Noth the with the Chiropetalum type. withstanding colpus transversalis

" Leucocroton the author prefers to place the pollen grains of flavicans in the Chiropetalum type.

Chiropetalum lanceolatum A. Jussieu Chiropetalum type; spheroidal. Wedermann 34 PI. 2 E P = = P: E 1. [U] XIV, 37,5 fi ca.

P.A.I. = Lumina 1 0,3. ca. /J,. Intectate.

Chiropetalum canescens Phil. Chiropetalum type; prolate spheroidal. Wedermann 773 Lumina 1-2 Intectate. [U] fi. Aonikena patagonica Spego. Chiropetalum type; prolate spheroidal.

P = E = P:E = [= Chiropetalum patagonica (Spegg.) 34,5 n 30,5 n 1,12.

O’Donn. P.A.I. = Lumina 1-2 et Lourteig] 0,3. fi. Eyerden, Beetle and Grond 24370 [K] PI. XIV, 4

Leucocroton flavicans Muell. Arg. Chiropetalum type; subprolate. *= Ekman 13243 [K] PI. XIV, 5 P 30,5 n E = 25,5 P:E = 1,19.

Colpus transversalis without costae.

P.A.I. = Lumina 1 0,4. ca. fi.

Ditaxis type

Tricolpate; oblate to suboblate. The pollen grains are bi-laterally symmetric.

One lobe of the three-lobed pollen grain is smaller than the other two.

and Colpi long not very narrow. Tectate; psilate; not reticulate.

has the This type bi-symmetric pollen grains. Of three lobes one is smaller than the other two. This curious shape was observed in six

of Ditaxis. candicans does not these bi- species Argythamnia possess symetric pollen grains.

Taxonomic discussion

It could not be investigated whether other species of Argythamnia

perhaps do show the Ditaxis type. Croizat did Ditaxis (1945) not see any reason to separate and Argythamnia. The difference in pollen type, however, supports the opinion of Pax and K. Hoffmann (1931), who maintain Ditaxis next to Argythamnia.

Pax Ditaxis fendleri (Muell. Arg.) et Ditaxis type; oblate.

K. Hoffm. P = E = P:E = 30,5 n 51 n 0,60.

Staffers 1703 [U] PI. XIV,_1 P.A.I. = 0,15. Ditaxis catamarcensis (Griseb.) Pax Ditaxis type.

Brizuela 759 P = E = 42 P:E [U] 33 n n = 0,79.

Ditaxis diversiflora Glokey Ditaxis type. Clokey 7576 [U] Some pollen grains 4—colpate. A. Ditaxis fasciculata Vahl ex de Juss. Ditaxis type.

Boldingh 2733 A [U] P = 43 /i E = 50 n P:E = 0,86.

= P.A.I. 0,2 — 0,25.

Ditaxis lancifolia Schlechtend. Ditaxis type.

Broadway 9257 [U] P.A.I. = 0,2 — 0,25. Ditaxis salina Pax et K. Hoffm. Ditaxis type. Pedersen 2638 [U] POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 67

plate xiv. 1. Ditaxis fendleri; 2. Chiropetalum lanceolatum; 3. Argythamnia candicans; 4. Aonikena patagonica; 5. Leucocroton flavicans; fi. Lasiocroton macrophyllus. 68 w. PUNT

Argythamnia type

Stephanocolpate; oblate spheroidal.

Colpi long, not very narrow.

Tectate; on the top of the tectum a reticulum is superimposed.

the Although there are some similarities with Ditaxis type, shape as well as structure differ too much for the pollen grains to be placed in the same type.

Argythamnia candicans Sw. Argythamnia type; 4 (-3)-colpate.

3401 B. PI. 3 P = P:E = Boldingh [U] XIV, 42 n E=45/t 0,93.

P.A.I. = 0,5.

Lasiocroton type

Tricolpate or stephanocolpate; spheroidal to oblate spheroidal.

Colpi wide; operculum present; no costae present. reticulum Tectate; psilate; no present.

between the The difference Chiropetalum type and Argythamnia type is found in the absence of a reticulum.

According to Erdtman (1952) the pollen grains of Lasiocroton macrophyllus are reticulate. With the aid of a phase contrast microscope it was possible to conclude, that the pollen grains of the Harris 11868 specimen are certainly not reticulate.

‘Taxonomic discussion

Lasiocroton and Adelia, together with Leucocroton (p. 66), formed the series Adeliiformes (Pax and K. Hoffmann 1914, 1931) in the subtribe

Mercurialinae. These three genera are certainly related by the following characters:

in male well in the 1. Disc present the as as female flowers. This disc is usually annular. 2. Ovarium rudiment in the male flower absent. 3. Petals absent. Number of sepals usually 5. 4. Plants usually dioecious and only growing in the New World.

Griseb. Lasiocroton oblate Lasiocroton macrophyllus (Swartz) type; spheroidal.

= Harris 11868 [K] PI. XIV, 6 P = 18,5 n E 19,5 fi P:E = 0,95.

P.A.I. = 0,3.

Adelia ricinella Linn. Lasiocroton type; spheroidal.

P = E = 33 Rutten-Pekelharing [U] (3-) 4-coIpate. [i.

Fuertes 833 [U] Operculum narrow. P.A.I. = 0,4-0,5.

Cephalomappa configuration

Tricolpate.

Colpi very short; costae colpi present.

Cephalomappa type

Tricolpate; oblate spheroidal.

Colpi very short; costae colpi present.

Tectate; intra-reticulum coarse.

differs from The Cephalomappa type completely all other types in 69 POLLEN MORPHOLOGY OF THE EUPHORBIACEAE the Crotonoideae. the reticulum the short Besides very coarse colpi are and bordered by distinct costae colpi.

Taxonomic discussion

The is related to those in the genus Cephalomappa certainly Cladogynos type (p. 93).

Cephalomappa malloticarpa J. J. Smith Cephalomappa .. type.

= Herb. Batav. 924.536. 117 P = E = P:E Lugd. [L] 30,5 fi 32,5 p 0,94.

PI. 5 ca. 4 1 Lumina XV, Colpi length / . 2-3 fi.

SUMBAVIA CONFIGURATION

Tricolporate - stephanocolporate; usually Polar axis shorter than Equatorial axis.

Colpi wide or narrow.

Tectate or intectate; reticulate. Reticulum coarse.

The most important character of this configuration is the coarse reticulum. Some species in the Cladogynos configuration (p. 93) also

have a fairly coarse reticulum but inthat case they have a Polar axis larger than the Equatorial axis. In the Sumbavia configuration the

have Polar than pollen grains usually a axis shorter the Equatorial

axis.

Taxonomic discussion

Most in this the genera configuration belong to Chrozophoreae (Bentham, 1880; Pax and K. Hoffmann 1912c, 1931). These authors this tribe in Bentham’s third is split up groups. group comparable with the subtribe Regulares of Pax and K. Hoffmann, in which and found. Sumbavia, Chrozophora Caperonia are

Sumbavia type

Tricolporate; oblate spheroidal to oblate. transversalis Colpus large; broad or long and narrow.

Colpi long; costae colpi present or absent.

Intectate; reticulate. Reticulum coarse.

The of the and pollen grains Sumbavia type are always tricolporate have distinct reticulum. differ from the and a They Chrozophora type Caperonia subtype by the number of colpi and from the Philyra subtype

by the coarse reticulum and elongated colpus transversalis. In 1952 Erdtman described pollen grains of Monotaxis grandiflora

which are subprolate and have a membrana granulata. This discrip- tion is not in accordance with the data found by the author. The

pollen grains examined were suboblate and had no membrana

is the granulata. The exine structure, however, quite same.

Taxonomic discussion

In the system of Pax and K. Hoffmann (1931) Thyrsanthera and This is in Sumbaviopsis are placed next to Sumbavia. agreement with the close relationship of the pollen grains. 70 W. PUNT

Monotaxis differs from the in the Sumbavia other genera type by the _ of and absence stellate hairs and the presence of a disc an ovarium rudiment in the male flowers. The flowers have, however, also five

in petals as most genera of the Sumbavia type- „ . . . in Sumbavia and many respects Melanolepis resembles Sumbaviopsis. As with these there is disc ovarium rudiment in the genera no or male flower. On other hand female the the flower possesses a disc. stellate and The plants have hairs, they are monoecious show similarity in the formof the leaves. Melanolepis, however, has no petals.

Baillon (1858) therefore calls Melanolepis a Sumbavia without petals.

Mueller (1866), Bentham (1880) and Pax and K. Hoffmann see

Mallotus as nearest relation of Melanolepis. An accurate comparison of the corresponding characters will have to decide whether Melanolepis is closer related to Mallotus than to Sumbavia and Sumbaviopsis.

Sumbavia rottleroides Baill. Sumbavia type; oblate spheroidal.

Merrill Sp. Blancoanae 993 [L] P = 43ju E = 46 P:E = 0,93.

PI. XV, 2 m:e = 0,6. P.A.I. = 0,35.

Costae absent. Lumina 3-4 colpi /x. Smith suboblate. Sumbaviopsis albicans J. J. Sumbavia type;

Backer 19016 [L] P = 32 n E = 38,5 fi P:E = 0,80.

P.A.I. = Lumina 0,3. 1-2 /x. Costae colpi.

Thyrsanthera suborbicularis Pierre ex Sumbavia type; suboblate.

Gagnepain P = E = 52 P:E = 43,5 i* n 0,84.

Pierre PI. P.A.I. = Lumina 512 [K] XV, 3 0,3. 1-2 /x. Costae colpi absent.

Melanolepis multiglandulosa (Reinw. ex Sumbavia type; suboblate.

Reich.f. Zollinger P = £ = P:E = Blume) et 32 /* 38,5/1 0,82.

= Hort. 1 P.A.I. — Lumina 1-3 Bogor. 2127 [U] PI. XV, 0,3 0,35. /x. Costae transversales.

Monotaxis grandiflora Endl. Sumbavia type; oblate.

Pritzel 1900 PI. 4 P = E = 36 P:E = XI, [U] XV, 30,5 /j. 0,84.

m:e < 0,5- P.A.I. = 0,15.

Colpus transversalis long and narrow. Lumina 1-2 fi.

Chrozophora type

Stephanocolporate; suboblate - oblate. Colpus transversalis broad, isodiametric; costae. Colpi short; costae colpi. Intectate (?); reticulate. Reticulum coarse.

in the The lumina of the reticulum are much larger Chrozophora of the Sumbavia Besides type than in any other type configuration. the number of is this character the colpi are short and colpi large (at least six). In the subfamily of the Crotonoideae pollen grains with more than three or four colpi are rather rare. Only the related

Caperonia type has also six colpi.

Chrozophora plicata (Vahl) A. de Juss. Chrozophora type; (7-) 8 (-9)-colporate;

Feinbrun etc. 49169 A. [U] PI. XV, 6 suboblate — oblate.

P 60 E = 80 P:E = = n ft 0,75.

m:e = ca. 1. P.A.I. > 0,5. Lumina 4-6 fx.

Chozophora tinctoria (Linn.) A. de Juss. Chrozophora type. 6-colporate. Faure 31126 A. [U] POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 71

plate xv. 1. Melanolepis multiglandulosa; 2. Sumbavia rotlleroides; 3. Thyrsanthera suborbiculatus; 4. Monotaxis grandiflora; 5. Cephalomappa malloticarpa; 6. Chrozophora plicata. 72 W. PUNT

Caperonia type

Stephanocolporate or tricolporate; oblate spheroidal - prolate spheroidal.

Colpus transversalis broad, circular - broad elliptic.

Colpi long and narrow; costae colpi absent. Intectate; reticulate. Lumina fairly small. Columellae elongated.

This type resembles the Chrozophora type in its number of colpi

(usually six). The colpi are, however, longer, and the lumina of the reticulum much smaller. The Philyra subtype differs from the Sumbavia type by its large circular colpus transversalis.

Taxonomic discussion

Mueller and Bentham included in (1866) (1880) Philyra the genus Argythamnia. Pax and K. Hoffmann (1912c, 1931) separated Philyra from this genus and referred it close to Caperonia. Pollen-morpholog- the is related than d ically genus more to Caperonia to Argythamnia an its allies.

Caperonia subtype

Pollen grains stephanocolporate.

Caperonia palustris (Linn.) St. Hill. Caperonia subtype; oblate spheroidal.

1044 PI. 4 P = 32 E = 33 P:E = Lanjouw [U] XVI, n n 0,94.

m:e ca. 1. P.A.I. = 0,3. Lumina 1 ca. fi.

Caperonia serrata Presl Caperonia subtype; spheroidal.

de Wit 429 P E 39 = [WAG] = = n. P.A.I. 0,5. Caperonia corchoroides Muell. Arc. Caperonia subtype. Rombouts 358 [U]

Philyra subtype

Pollen grains tricolporate.

Philyra brasiliensis Klotzsch Philyra subtype; prolate spheroidal.

Hassler 12323 PI. 2 = 35 P E = P;E = [K] XVI, 38,5 fi n 1,10.

m: e = 0,7. P.A.I. = 0,4. Lumina 1-2 ft.

Caryodendron type

Tricolporate; oblate spheroidal - suboblate. view In polar pollen grains convex triangular.

Colpus transversalis broad; no costae present.

Colpi narrow; no costae colpi.

Intra-reticulum but lumina Tectate, tectum perforatum; psilate. coarse, small.

The related Caryodendron type is closely to the Sumbavia type. The

pollen grains are, however, tectate and the lumina of the intra- reticulum small. The is The are fairly tectum, moreover, perforate.

holes in the tectum small and visible with are very only high magni- fication.

Taxonomic discussion

Caryodendron is not closely related to the genera in the Sumbavia Bentham type. It lacks a stellate indument and petals. (1880) as

well as Pax and K. Hoffmann (1914, 1931) thought of a relationship POLLEN MORPHOLOGY OF THE EUPHORBTACEAE 73 with Alchornea. annular disc in the Caryodendron possesses, however, an female character flower, a never to be found in the genera of the Alchornea but in the of the Sumbavia type, always present genera type. This character is also in of present genera the Bernardia type and On other hand Speranskia type. the the authors cited above stated, that in their opinion Adenophaedra is closely related to Caryodendron.

Adenophaedra belongs pollen-morphologically to the Bernardia type (p. 75). The pollen grains of Caryodendron show indeed some resem- blance with this but the differences for type, are too many a com- bination of and Adenophaedra Caryodendron in the same type.

Caryodendron orinocense Karst. Caryodendron type; suboblate.

Krukoff 5553 PI. 3 P = E = P:E = [U] XVI, 29 fi 34,5 n 0,84.

m:e = 0,4. P.A.I. = 0,3.

Lumina 1 muri thick. ca. /i; Caryodendron grandifolius Muell. Arc. Caryodendron type; oblate spheroidal.

Kuhlmann et Ducke 16598 [U] P = 31,5 n E = 33 p P:E = 0,95.

P.A.I. = 0,2.

Nealchornea type

Tricolporate; oblate spheroidal. In polar view the pollen grains circular.

Colpus transversalis broad; ora large. Colpi short and wide.

Intectate; reticulate. Reticulum coarse.

The Polar shorter than the pollen grains have a axis Equatorial

axis and there is also a reticulum with large lumina. For these reasons in the the type is placed Sumbavia configuration. It differs from the

other types by the three short colpi.

Taxonomic discussion

Nealchornea is related discussed in other of not to any genus types

the Sumbavia configuration. Its nearest allies are perhaps Hamilcoa, Plagiostyles and Pimeleodendron (p. 103). Striking corresponding characters with these the short sessile anthers and genera are very to thickened pedicels. Pax and K. Hoffmann the in the subtribe (1931) put genus

Cluytiinae with e.g. Trigonostemon, Moultonianthus and Trigonopleura. The latter three all in different and genera are placed pollen types even in different configurations.

Nealchornea yapurensis Huber Nealchornea type.

Krukoff 4967 PI. 1 P = E = P:E = [U] XVI, 27 fi 30 /* 0,90.

= Lumina 3-4 m:e ca. 1. fi.

Bernardia configuration

Tricolporate or stephanolcoporate (except Erismanthus type). Usually Polar axis larger than Equatorial axis.

Colpi narrow; costae colpi.

Tectate or in tectate; reticulate. Reticulum fine; lumina <2 // ( Cyttaranthus without reticulum).

The types of the Bernardia configuration are finely reticulate and Polar have usually a axis larger than the Equatorial axis. Cyttaranthus 74 W. PUNT

plate xvi. 1. Nealchornea yapurensis; 2. Philyra brasiliensis; 3. Caryodendron orinocensis; 4. Caperoniapalustris; 5. Pseudagrostistachys africana; 6. Heterocalyx laoticus; 7. Cyttaranthus congolensis; 8. Bernardia pulchella. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 75

in only is not reticulate, but other respects the pollen grains of this resemble the genus closely Speranskia type. Although placed in this configuration by their fine reticulum and prolate shape, the Moul- tonianthus type and the Clutia type differ largely from the Bernardia and the type Speranskia type.

Bernardia type

Tricolporate; spheroidal prolate - subprolate. Pollen grains in polar view distinctly three-lobed. Colpus transversalis small; costae. small Colpi narrow; costae colpi. P.A.I. < 0,25.

lumina ca. 1 Intectate; finely reticulate; fi.

from the The Bernardia type differs Speranskia type by its distinctly three-lobed pollen grains.

Taxonomic discussion

Mueller originally described Adenophaedra as a section of Bernardia. In later publications he raised it to a separate genus. Bentham (1880) and Pax and K. Hoffmann maintained the and (1931) two genera

even placed them in a far-away group to which Alchornea belongs. of the showed close Pollen-morphological study two genera a relation, so it seems better to maintain Adenophaedra in the vicinity of Bernardia. Both restricted the New World. genera are to

Bernardia pulchella (Baillon) Muell. Bernardia type; prolate spheroidal.

P E = P:E = = 25,5 ft 24/i 1,07.

Tessman 6078 [U] PI. XVI, 8 m:e = ca. 0,5. P.A.I. = 0,15. Bernardia Bernardia lorentzii Muell. Arc. type.

Schulz 1554 P = E = P:E = [U] 29 n 25 n 1,17.

P.A.I. = 0,2.

Bernardia corensis (Jacq..) Muell. Arg. Bernardia type.

665 B. P 31 E = P;E = Boldingh [U] = iu 25 /x 1,24.

P.A.I. = 0,2. Adenophaedra minor Ducke Bernardia type.

Herb. Rio 10386 P = 28 E = 27 P:E = [U] n /i 1,04. transversalis Colpus narrow;

m:e < 0,5. P.A.I. = 0,1-0,15.

Speranskia type

Tricolporate; spheroidal — prolate spheroidal. Pollen grains in polar view

convex triangular. transversalis absent. Colpus large; costae present or

Colpi narrow; costae colpi. Sometimes costae indistinct. Tectate; intra-reticulum present or rarely absent ( Cyttaranthus).

This type looks somewhat like the Bernardia type but differs by its polar view and the shape of the colpus transversalis. Cyttaranthus

belongs undoubtedly to this type but lacks the fine reticulum.

Taxonomic discussion

Genera with a Speranskia type are only found in the Old World.

They have several characters in common.

1. In the female flowers always a disc present. 2. Anthers usually pendulous; connectives frequently appendiculated. 76 w. PUNT

3. In the male flowers an ovarium rudiment is wanting except in

some Agrostistachys species. 4. The Asiatic and extrastaminal disc. The genera have petals an African representatives frequently lacks petals, while glands are

always present on the receptaculum. hairs 5. Stellate never present.

Pax K. Hoffmann Speranskiapekinensis et Speranskia type; subprolate.

Bullock 10 Mai. 1888 PI. 8 P = P:E [K] XVII, 28,5 n E=24/t = 1,16.

m:e = 0,5-1. P.A.I. = 0,10. Lumina 1 < /s. Pseudagrostistachys africana (Muell. Arg.) Speranskia type; subprolate.

Pax K. Hoffm. P = 33 E = P;E = et /i 26,5 /* 1,24.

Moller and Quintus 16 [U] PI. XVI, 5 m:e < 0,5. P.A.I. = 0,3. Lumina 1 ca. fi.

Cyttaranthus congolensis Leonard Speranskia type; prolate spheroidal.

Gollens 3541 7 P = 30 E = P:E = [K] PI. XVI, n 28,5 /i 1,05.

P.A.I. = 0,35. Not reticulate!

Agrostistachys indica Dalz. Speranskia type; oblate spheroidal.

Stocks P = E = P:E = [U] 31,5 fi 33,5 n 0,94.

m:e < 0,5. P.A.I. = 0,25. Lumina 1-2 ofthe ft.Margo (thinning ektexine). Agrostistachys sessilifolia (Kurz) Pax et Speranskia type; subprolate.

K. Hoffmann P = E = P:E = 26,5 /j. 23,5 fi 1,12.

East Ind. Comp. 4739 [U] P.A.I. = 0,2-0,25. Costae transversales. Margo (thinning of the ektexine). Heterocalyx laoticus Gagnep. Speranskia type; spheroidal.

Kerr 20895 PI. 6 P = E = 30 P.A.I. = [K] XVI, /i. 0,25. Lumina 1-2 ofthe /(. Margo (thinning ektexine).

Argomuellera macrophylla Pax Speranskia type; spheroidal.

de PI. 3 P = E = P;E = Wit 32 [WAG] XVII, 25,5 n 25 /i 1,02.

m:e = 0,7-0,8. P.A.I. = 0,4. Lumina 1 Costae transversales ca. /i.

absent.

119 A P = 30 E = P:E Swynnerton [BM] fi 28,5 n = 1,08.

In other characters as above.

Discoglypremna caloneura (Pax) Prain Speranskia type; prolate spheroidal.

Zenker 2643 P=27 E = 25 P:E = [L] ii ,m 1,09.

P.A.I. = Lumina 1 0,25-0,3. ca. fi.

Moultonianthus type

Tricolporate; spheroidal. In polar view the pollen grains circular.

Colpus transversalis narrow and small; costae.

Colpi narrow and long; costae colpi. Intectate; reticulum fine.

The pollen grains of the Moultonianthus type are finely but distinctly reticulate and are therefore placed in the Bernardia configuration.

The shape, polar view and colpus transversalis of this type differs from the other in greatly types this configuration.

Taxonomic discussion

According to v. Steenis (1948) Moultonianthus is related to Eris- manthus in several characters. Unfortunately pollen grains of Eris-

manthus indochinensis do not agree with those of Moultonianthus leem- POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 77

rela- bruggianus. Perhaps other species of Erismanthus will show more tionship in their pollen-morphology.

Moultonianthus leembruggianus (Boerl. et Moultonianthus type.

Koord.) v. Steenis P= E = 23,5 fi. m;e < 0,5.

P.A.I. = Lumina 1-2 Sarawak 464 [L] PI. XVII, 1 0,4. n-

Erismanthus type

Tricolpate; oblate spheroidal. In polar view pollen grains circular. Rim of the Colpi narrow. colpi irregularly ruptured. Tectate; psilate. Columellae short.

Pollen grains of Erismanthus indochinensis distinctly differ from the There Moultonianthus-type. are no composite apertures and the grains

are tectate. Erdtman (1952) examined Erismanthus oblique and on the did find in contrary composite apertures this specimen.

Erismanthus indochinensis Gagnep. Erismanthus type.

D’Alleizette 942. 20-4-1908 P = 24 E = P:E = [L] n 25,5 n 0,93. PI. 4 P.A.I. XVII, = 0,4.

Clutia type

Tricolporate; subprolate. In polar view the pollen grains triangular. Colpus transversalis small; costae.

Colpi narrow; costae colpi. Margo present (thinning of the ektexine). Tectate; intra-reticulum indistinct.

The Clutia type strongly recalls the Phyllanthus pentaphyllus subtype

in the subfamily of the Phyllanthoideae. The type differs, however, the of the The from by shape colpus transversalis. Clutia type differs the Bernardia type by its polar view. The Bernardia type is three-lobed,

the Clutia type triangular.

Taxonomical discussion

This African genus stands alone in the Euphorbiaceae. The in- those of florescence and habit are Phyllanthus; but the essential characters those of are the Chrozophorae (Bentham, 1880).

Clutia paxii Knauf Clutia type.

Crookewit = = = 198 [WAG] PI. XVII, 2 P 35 /i E 27 n P:E 1,30.

m:e < 0,5. Clutia natalensis Bernh. Clutia type.

1935 P = 43 E 33 P:E Wylie Jan. [U] n = n = 1,30. Reticulum indistinct.

Clutia abyssinica Jaub. et Spach Clutia type.

Stolz 1876 P E == 40 P:E = [U] = 52 fi n 1,30. Reticulum indistinct.

Clutia rubricaulis Eckl. ex Sond. Clutia type.

C. alaternoides P — 54 E = 41 P:E = [= Linn.] fi fi 1,30. Lanjouw 165 [U] Reticulum indistinct.

Mallotus configuration

Tricolporate - stephanocolporate (4). Polar axis usually shorter than Equator- ial axis.

Colpi narrow. Tectate (tectum perforate in Blumeodendron type); usually not reticulate; columellae short, capita indistinct. 78 W. PUNT

plate xvu. 1. Moultonianthus leembruggianus; 2. Clutia paxii; 3. Argomuellera macro- phylla; 4. Erismanthus indochinensis; 5. Mallotusalbus; 6. Cleidionjavanicum; 7. Macaranga spinosa; 8. Speranskia pekinensis; 9. Trewia nudiflora. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 79

of The most important characters the Mallotus configuration are the short columellae and the indistinct capita. Besides these important the characters pollen grains are usually not reticulate.

- - - - - Mallotus type, Blumeodendron type, Acalypha type, Alchornea type, and Discocleidion type Mareya type are closely related and differ only in minor points. The Ricinus type and Pera type are connected by the very narrow colpi and nearly visible columellae. They certainly belong to the Mallotus configuration although the shape of the pollen grains is often prolate. The Seidelia type and Leidesia type are related to each other, es- pecially in their exine structure and polar view.

The Microdesmis type and Cheilosa type are placed in the Mallotus configuration because of their shape and short columellae. The differences with the other types in this configuration, however, are considerable.

Mallotus type

Tricolporate - stephanocolporate (4); oblate spheroidal - suboblate. Some- times spheroidal. Colpus transversalis usually small; costae.

Colpi narrow; costae colpi. Tectate; psilate or scabrate. Rarely intra-reticulate (Adriana).

The pollen grains are easily distinguished from the other types.

The colpi, are short (P.A.I. is at least 0,4) and the shape is usually oblate spheroidal. The columellae are so short, that only with difficulty

the tectum can be distinguished from the endexine. Costae colpi distinct.

Taxonomic discussion

In the system of Mueller (1866) genera of the Mallotus type are all found in his subtribe Euacalypheae. Bentham (1880) placed them in the subtribe Acalypheae and Pax and K. Hoffmann (1914, 1931) in In the subtribe Mercurialinae of the tribe Acalypheae. all three systems the mixed with genera are up those, closely allied to them in the

Acalypha type, Alchornea type, Blumeodendron type, Discocleidion type characters and Mareya type. Corresponding are:

disc in 1. A is wanting the male as well as in the female flowers.

2. An ovarium rudiment is wanting.

3. Usually numerous stamens are inserted on a convex receptaculum

(Macaranga with few stamens has no receptaculum). Most times the receptaculum is glabrous. Sometimes it is provided with

glands (some species of Mallotus and Pycnocoma) or hairs (Wetria).

4. The of the in the Old Avel- majority genera grows World; only lanita is from Chile.

Mallotus subtype

Pollen grains psilate. 80 w. PUNT

Mallotus albus (Roxb.) Mueix. Arg. Mallotus subtype; oblate spheroidal.

Thomson 5 P = E = = [U] PI. XVII, 30 n 30,5 n P:E 0,98.

m:e < 0,5. P.A.I. = 0,4. Mallotus claoxyloides (F. v. Mueller) Mallotus subtype.

Muell. Arg. P = 30 E = P:E = n 32,5 /u 0,95. 1874 Buysman [U] P.A.I. = 0,4. Mallotus miquelianus (Scheff.) Pax et Mallotus subtype.

K. Hoffm. P = E 20 = 21 = // /u P:E 0,95.

Rutten-Kooistra 27 [U] P.A.I. = 0,4. Muell. Arg. Mallotus Too Mallotus repandus (Willd.) subtype. young. Griffith 4760 [U] lanceolatus Gagnep. Coelodiscus Mallotus™ subtype.

D’Alleizette = = Jan. 1909 [L] P 25,5 /I E 27 /i P:E = 0,94.

P.A.I. = 0,4.

Trewia nudiflora Ltnn. Mallotus subtype.

Hohenacker 453 [U] PI. XVII, 9 P = 27/r E = 30,5 n P:E = 0,89. short. Colpi very P.A.I. > 0,75. Avellanita bustillosii Philippi Mallotus subtype.

P = E P:E = Philippi [BM] 25,5 n = 26 n 0,98.

Costae colpi indistinct. P.A.I. = 0,45. Cordemoya integrifolia (Willd.) Baillon Mallotus subtupe.

Gover. Pires to Kew Nov. 1908 P = 20 E = P:E = [K] n 21,5 0,93.

P.A.I. = 0,7. Coccoceras borneënse J. J. Smith Mallotus subtype; 3-4 colporate.

H. Endert P = E = 39 E = F. 2078 [L] 37,5 n P: 0,96.

short. P.A.I. = Colpi very 0,7. Deuteromallotus acuminatus (Baillon) Mallotus subtype.

Pax et K. Hoffm. P = E = P:E = 20 iu 22,5 fi 0,88. D’Alleizette Mad. Nov. 1908 short. [L] Colpi very P.A.I. > 0,7. Wetria macrophylla (Blume) J. J. Smith Mallotus subtype; 4- (3) colporate.

Cult. Hort. IXA. 124 P = E = 40 P.A.I. = Bog. [U] n 0,5. Adriana quadripartita (Labile.) Gaudich. Mallotus subtype.

F. v. Freemantle 1861 P = £ = P;E = Mueller, [U] 33,5 ft 35// 0,96. P.A.I. > 0,5. Intra-reticulate. Cleidion javanicum Blume Mallotus subtype.

= Cult. Hort. IX A. 38 P E —27 P:E = Bog. [U] 25,5 n n 0,95. PI. XVII, 6 P.A.I. > 0,7. Cleidion angustifolium Pax et K. Hoffm. Mallotus subtype. 19 Le Rat 468 [P] P = fi E = 18 /< P:E = 0,95. P.A.I. > 0,7. Macaranga spinosa Muell. Arg. Mallotus subtype.

1292 PI. 7 P = E = P:E Steiner [U] XVII, 14,5 fi = ca. 1.

P.A.I. > 0,5.

Macaranga harveyana (Muell. Arg.) Mallotus type.

Muell. Arg. P = E 17 P:E 1. 17 n = n = ca. Yuncker 15980 [U]

Wars. Mallotus P = E = Macaranga densiflora subtype; 17 p. Gjellerup 236 [U]

Pycnocoma subtype

Pollen grains scabrate.

from This subtype differs the Mallotus subtype by the scabrae on

the tectum. In Pycnocoma cornuta the colpi are longer than those in other Mallotus The of pollen grains of the type. colpi Pycnocoma macrophylla, however, are as short as the others.

Pycnocoma cornuta Muell. Arg. Pycnocoma subtype.

= 3003 PI. 1 P = E P;E = Leeuwenberg [U] XVI11, 33,5 p 35,5 p 0,94.

m:e = 0,4. P.A.I. = 0,3. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 81

Pycnocoma macrophylla Bentham Pycnocoma subtype.

Zenker 1251 P = E = 32 P:E = [L] 30,5 fi fi 0,95.

P.A.I. > 0,5.

Blumeodendron type

Tricolporate; oblate spheroidal. transversalis small and Colpus narrow; costae.

short and Colpi very narrow; costae colpi. Tectum that be perforatum may regarded as a coarse reticulum.

the This type is closely related with Mallotus type. The tectum, however, is perforated. The holes are rather wide and it is perhaps of reticulum. muri of the reticulum better to speak a coarse The are thick and consist of small columellae. many

Taxonomic discussion

The affinities of Blumeodendron with Botryophora are extensively explained by Airy-Shaw (I960).

in with Without doubt Ptychopyxis has several characters common Blumeodendron and Botryophora.

1. In the male flowers a disc and an ovarium rudiment are absent.

Many stamens inserted on a receptaculum. In 2. the female flowers a disc is present. (Airy-Shaw 1960, states,

that in Ptychopyxis at least some species certainly have a disc.)

Blumeodendron Kurz tokbrai (Blume) Blumeodendron type.

= Achmad 216 [L] PI. XVIII, 6 P =21/t E 23 P:E = 0,91. Ptychopyxis costata Miquel Blumeodendron type.

collector 6740 P = E = 21 P:E = Kings [L] 18,5 n n 0,88. Ptychopyxis kingii Ridley Blumeodendron type.

de Haviland 3673K P E = P:E = et Hose [K] = 19,5 /j. 21 /i 0,83. Blumeodendron Botryophora geniculata (Miq,.) Beumee ex type.

P = E = P:E = Airy-Shaw 22 n 23,5 n 0,93. Docters 7707 P.A.I. somewhat v. Leeuwen [L] = 0,5-0,6. Colpi longer.

Acalypha type

Tricolporate or stephanocolporate; oblate spheroidal to suboblate. The pollen

grains are quasiporate. With high magnification the apertures are undoubtedly

composite apertures. Colpus transversalis and colpus of the same size; costae. Tectate; psilate.

The Acalypha type is undoubtedly related to the Mallotus type...... The dimensions of the colpi and the colpi transversales, however, are

so small that the composite apertures resemble pori.

Acalypha indica Linn. Acalypha type-

PI. 4 P = E = 16 P:E = Dewan, 12-9-1957 [U] XVIII, 14,5 /t [ji 0,90. Acalypha aronioides Pax et K. Hoffm. Acalypha type; 4—5 (col)-porate.

1064 P"= 14 E = P:E = Ellenberg [U] pc 16,5 fi 0,85.

Acalypha racemosa Wallich ex Baillon Acalypha type; 3 (col)-porate.

Versuchsanst. 410 P'= E P:E = [U] 12 n = 13,5 /x 0,89. Acalypha platyphylla Muell. Arg. Acalypha type; 3 (col)-porate.

Killip et Garcia 33764 [U] P = 13,5 /i E = 14,5 fi P:E = 0,93. Acalypha scandens Bentham Acalypha type; 4—5 (col) porate.

P'= = = Y. Mexia 6386 [U] PI. XVIII, 5 17,5 E 19,5 n P:E 0,90. Too Acalypha diversifolia Jacq. Acalypha type. young. Versteeg 466 [U] 82 W. PUNT

Alchornea type

Tricolporate; spheroidal to suboblate. Colpus transversalis with costae.

Colpi narrow; costae colpi. Operculum present. Tectate; psilate.

In and the shape structure the Alchornea type is related to Mallotus

type. The pollen grains differ from the latter type by the presence of an operculum.

Taxonomic discussion

of have much those of the Genera this type resemblance with In the Mueller Bentham Mallotus type. systems of (1866), (1880)

and Pax and K. Hoffmann (1931) they are mixed up with them. Indeed the characters of this well with those group correspond in There described the Mallotus type (p. 79). are only a few indistinct differences.

1. Number of stamens is often less than 20. Neotrewia, Gavarretia and have the Mallotus Polyandra up to 60 stamens (In type up to several hundreds). in with 2. Receptaculum usually flat and peltate (not species many in stamens). As the Mallotus type glands are absent or scarce (Alchornea and Neotrewia).

and which Coelebogyne Lepidoturus are genera, nowadays are con-

sidered as belonging to Alchornea. Originally Croizat placed Adenophaedra prealtum (Croizat) Croizat in the Cleidion This has its widest in genus (1943c). genus spread and in Asia was said to have some representatives America. After- wards that all American Cleidion Croizat’s opinion was species belong to Adenophaedra (1946a). Pollen-morphological investigation shows,

that pollen grains of the species Adenophaedra prealtum on no account resemble those of Adenophaedra minor Ducke. The diagnosis of A de-

no prealtum however, fits into the new phaedra , completely genus

Polyandra described by Leal (1951). Leal moreover published a this photograph of the pollen grains of genus, from which it is clear like that the pollen grains belong to the Alchornea type those of Adenophaedra prealtum.

Alchornea villosa (Benth.) Muell. Arg. Alchornea type; oblate spheroidal.

Bosch Proefst. F. 1152 [U] PI. XVIII, 2 P = 25 E = 26,5 P:E = 0,94.

m:e = 0,6. P.A.I. = 0,4.

Alchornea Muell. Arg. Alchornea rugosa (Lour.) type.

Elmer 14353 P=24 u P:E == [U] J E=26,5 n 0,92. P.A.I. > 0,5. Alchornea schomburgkii Klotzsch Alchornea type.

Hilleris-Lambers 1922 P = = P:E = 1. 24,5 fi _E 24,5ji

Alchornea Muell. Alchornea P = E = triplinervia (Spreng.) type. 27 /i. Arg.

Regnell III. 1066 a [U] Lepidoturus laxiflorus Benth. Alchornea type.

Alchornea = = [= laxiflora (Benth.) Pax P = 20,5 n E 22 /M P:E 0,93.

et K. Hoffmann] P.A.I. = 0,35-0,4. Faulkner 531 [K] POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 83

Coelebogyne ilicifolia J. Smith [= Alchornea Alchornea type.

= = Muell. P = E 23 P:E ilicifolia (J. Smith) Arg.] 20 p n 0,88. P.A.I. F. v. Muell., Rockhampton 1873 = 0,4-0,45. [K] PI. XVIII, 7 Neotrewia cumingii (Muell. Arg.) Pax Alchornea type.

P:E = K. Hoffm. P = 21 E = et /x 22,5 fi 0,93.

Elmer 15623 [U] P.A.I. = 0,4. Operculum consists of

only one row of pila.

Gavarretia terminalis Baill. Alchornea type.

Ducke P 5 E = P;E = 23511 [U] = 27, fi 30,5 0,91.

P.A.I. = 0,3.

Conceveiba simulata Steyermark Alchornea type.

Krukoff 6643 P = E = P:E = [U] 19,5 n 22,5 n 0,88.

P.A.I. = 0,4. Scabrate. Pax Alchornea Conceveibastrum martianum (Baill.) type.

= K. Hoffm. P = E = P:E et 21,5 /i 22,5 fi 0,93.

I.B.V. 23529 [U] P.A.I. = 0,4-0,45.

Veconcibea latifolia (Benth.) Pax et Alchornea type.

P = K. Hoffm. 25 /u E=27 lx P:E = 0,92.

[= Conceveiba latifolia Bentham] P.A.I. = 0,4. Spruce 2826 [BM] cordatum Aparisthmium (Juss.) Baill. Alchornea type.

Y. Mexia PI. 3 P E = 30 P:E = 6273 [U] XVIII, = 24 /* 0,80.

P.A.I. = 0,4.

Lautembergia multispicata Baill. Alchornea type.

D’Alleizette Nov. 1906 P = E = 25 P:E = Madag. [L] 21,5 /x n 0,86.

P.A.I. = 0,35. Lautembergia coriacea (Baill.) Pax Alchornea type; sometimes 4—colporate. D’Alleizette Madag. Oct. 1906 [L] Bocquillonia sessiliflora Baill. Alchornea type.

274 P = E = P:E = Balansa [L] 21,5 n 24,5 n 0,88.

P.A.I. = 0,35. Adenophaedraprealtum (Croizat) Croizat Alchornea type.

[= Polyandra L£al?] P = 25,5 n E = 29 n P:E = 0,88.

Krukoff 6602 [U] P.A.I. = 0,45.

Discocleidion type

Tricolporate; spheroidal to suboblate.

Colpus transversalis; costae as broad as the colpi. broad of the P.A.I. Colpi narrow; margo present (thickening ektexine). small, smaller than 0,2. Tectate; from psilate to coarsely warted. The ornamentation differs strongly.

shows The pollen type some resemblance to the Mareya type as well as to the Alchornea type. It differs from both types by its curious ornamentation. This ornamentation varies in the individual pollen grains. It is not certain whether other specimens of Discocleidion of rufescens will show the same variation ornamentation.

The type differs from the Mareya type by the presence of costae and from absence the Alchornea type by the of an operculum.

Taxonomic discussion

Discocleidion differs from the in the Alchornea genera type by the of disc in the female flowers and inserted presence a many glands on of the male flowers. These characters thereceptaculum place the genus the of the next to genera Mareya type.

Mueller first described Discocleidion as a section of Cleidion. Pax 84 W. PUNT

2. Alchornea plate xvra. 1. Pycnocoma cornuta; villosa; 3. Aparisthmium cordatum; 4. Acalypha indica; 5. Acalypha scandens; 6. Blumeodendron tokbrai; 7. Coelebogyne ilicifolia; 8. Mareya brevipes; 9. Discocleidion rufescens; 10. Kunstlerodendron sublanceolatum. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 85 and K. Hoffmann (1931) thought it better to raise the section to level which in the Bernardiiformes close Bernardia genus they place to and Mareya with their allies. Hurusawa (1954) at last reduced the this time of genus again to a section, Alchornea.

Pax Discocleidion rufescens (Franch.) et Discocleidion type.

K. Hoffmann P = 24 P:E = E=27 n 0,89.

D’Alleizette China Mai. 1908 [L] m:e = 0,7. P.A.I. = 0,1-0,15. PI. XVIII, 9

Mareya type

Tricolporate; oblate spheroidal to prolate spheroidal. In polar view pollen

grains convex triangular.

Colpus transversalis elongated; no costae.

Colpi narrow; no costae colpi present. Tectate; psilate.

The small. The axis is smaller than 30 pollen grains are largest fx. is from the Mallotus The Mareya type distinguished type by the absence of costae.

Taxonomic discussion

In and Hoffmann’s of this Pax K. system (1914, 1931) genera characters type belong to the Bernardiiformes. By the following the Alchornea genera differ from those in the Mallotus type and type:

1. In the female flowers a disc is present. male 2. The flowers have a receptaculum often set with glands.

A disc and an ovarium rudiment are wanting. (Mareyopsis is anomalous the of extra-staminal disc and the by presence glands absence of glands in the receptaculum.) 3. Anthers often have appendiculate connectives.

4. Plants usually grow in the Old World. (,Alchorneopsis in the New World.)

American The genus Alchorneopsis differs from the above characters

ovarium rudiment and the of hairs the by having an presence on receptaculum instead of glands.

Mareya bervipes Pax Mareya type; oblate spheroidal.

Zenker 1794 PI. 8 P 21 E = P:E = [L] XVIII, = v 23 0,91.

m:e < 0,5. P.A.I. = 0,3. Colpus membrane granulate. usambarica Pax Too reliable Crotonogynopsis Mareya type. young to give

Eggeling 3826 [K] measures.

Chondrostylis bancana Boerl. Mareya type; spheroidal,

Cult. Hort. II. I 8. E = P.A.I. = Bogor. [L] p = 25 ji. 0,3.

Kunstlerodendron sublanceolatum Ridl. Mareya type; oblate spheroidal.

39882 PI. 10 P E = 21 P:E = Sinclair [L] XVIII, = 20,5 n // 0,98.

P.A.I. = 0,3.

Mareyopsis longifolia (Pax) Pax et Mareya type; oblate spheroidal.

K. Hoffmann 18 = 19 P:E = P = /i E n 0,96.

Zenker 4228 [K] P.A I. = 0,2. Pax Neopalissya castaneifolia (Baill.) Mareya type; prolate spheroidal.

PerviI16 387 P = E = 21 P:E = [P] 22 n n 1,05.

P.A.I. = 0,25-0,3. 86 W. PUNT

Necepsia afzelii Prain Mareya type; prolate spheroidal. P E=21 P:E Leeuwenberg 2211 [U] =21,5 /i ft = 1,02.

P.A.I. = 0,3.

Amyrea humberti Leandri Mareya type; prolate spheroidal.

D’Alleizette Dec. 1905 [L] P = 24 /< E=21,5yu P;E = 1,13.

P.A.I. = 0,3. Alchorneopsisfloribunda (Benth.) Muell. Mareya type; oblate spheroidal.

= P = 18 n E = 19 P:E 0,95.

For.’Dept. 2889 [U] P.A.I. = 0,2. oblate Alchorneopsis trimera Lanj. Mareya type; spheroidal. P:E = = 22 = Lanjouw 1926; 49 [U] P 21/t E fi 0,96.

P.A.I. = 0,25.

Ricinus type

Tricolporate; shape differs from suboblate to subprolate.

Colpus transversalis narrow; no costae.

Colpi very narrow; no costae colpi present. visible in Tectate; psilate. Columellae very short, nearly some species.

The pollen grains resemble the Pera type, but the Ricinus type in It from the misses costae as the Mareya type. differs latter type by

narrow colpi and nearly visible columellae.

Taxonomic discussion

The genera in this type fall apart in two groups. The first group includes Homonoia and Lasiococca. These remarkable Ricinus, genera are for the large number of anthers crowded on repeatedly branched filaments.

The second group comprises Koilodepas only, which genus occupies in an isolated position the family (Airy-Shaw, 1960). Croizat (1942b)

as well as Airy-Shaw reduced Nephrostylus Gagnepain and Calpigyne

Blume to Koilodepas. According to Croizat, Calpigyne hainanense and

In the of Nephrostylus poilanei are synonyms. opinion Airy-Shaw,

Nephrostylus poilanei belongs to the species Koilodepas longifolium. Pollen

grains of both species are practically identical and show great structural resemblance with Koilodepas bantamense.

Ricinus communis Linn. Ricinus type; spheroidal.

Heerdt 531 P = 32 E = P:E 1. v. [U] p 32 p ca.

Versteeg 243 [U] PI. XIX, 3 m: e < 0,5. P.A.I. = 0,2. Lasiococca Ricinus symphylliifolia (Kurz) type; spheroidal,

= E = 23 = J. D. Hook. p fi. P.A.I. 0,45. Hort. Bogor. Cult. 6-4-1887 [L] Homonoia javensis (Blume) Muell. Arg. Ricinus type; prolate spheroidal. Hort. Bogor. IX A. 60 [U] PI. XIX, 2 P = 22,5 n E = 2l/x P:E = 1,08.

P.A.I. = 0,5. Costae transversales?

Homonoia riparia Lour. Ricinus type; oblate spheroidal-suboblate.

Heifer 4746 V = E P:E [U] 2bn = 29 = 0,88.

Koilodepas bantamense Hassk. Ricinus type; spheroidal-suboblate.

Hort. Bogor. IX C. 36 [U] Pi. XIX, 4 P = 20 fi E = 24 n P:E = 0,84.

m:e < 0,5. P.A.I. = 0,3.

Koilodepas hainanense (Merr.) Croizat Ricinus type; subprolate.

= hainanense P = 21 E P:E = [ Calpigyne Merr.] /x = 17,5 ft 1,18. S. K. Lau 3542 [P] PA.I. =0 3.

E = P:E = = = 17,5 1,17. [? Nephrostylus poilanei Gagnep. P 20,5 /<’ /x

D’Alleizette, Annam 11-4-1907 [L] P.A.I. = 0,3. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 87

platexix. 1. Leidesia procumbens; 2. Homonoia javensis; 3. Ricinus communis; 4. Koilodepas bantamense; 5. Chaetocarpus castanocarpus; 6. Pera bicolor; 7. Seidelia triandra; 8. Micro- desmis casearifolia. 88 w. PUNT

Pera type

Tricolporate; prolate spheroidal. Colpus transversalis small; costae.

but Colpi narrow; costae colpi narrow distinct. Columellae short. Tectate; psilate. very

visible The Pera type has the same very narrow colpi and nearly

columellae as the Ricinus type, but there are distinct costae colpi and

costae transversales present.

Pera bicolor (Klotzsch) Mueix. Arg. Pera type.

Ule 8409 PI. 6 P = E = 24 P:E = [U] XIX, 25,5 n yu 1,07.

m;e < 0,5. P.A.I. = 0,3. Pera glabrata (Schott) Baill. Pera type.

Reitz = = 4548 P = 19 E 18 P:E [U] n n 1,06.

P.A.I. = 0,5.

Seidelia type

Tricolporate; prolate spheroidal. In polar view the pollen grains distinctiy three-lobed.

Colpus transversalis small; costae.

Colpi narrow; no costae colpi. Tectate; psilate. Columellae short.

of The pollen grains this type are distinctly three-lobed and have costae transversales.

Seidelia triandra (E. Meyer) Pax Seidelia type.

Mus. PI. 7 P E P:E = MacGregor 1254[K] XIX, = 17,5 n = 16,5 /s 1,06.

m:e = 0,6. P.A.I. = 0,25.

Leidesia type

Tricolporate; oblate spheroidal. In polar view the pollen grains distinctly three-lobed.

Colpus transversalis narrow and long; no costae.

Colpi narrow; no costae colpi. Narrow operculum. Tectate; psilate. Columellae short.

The Leidesia type resembles the Seidelia type in its polar view and exine structure. It differs, however, by the absence of costae and the

addition of a narrow operculum.

Taxonomic discussion

Leidesia and Seidelia are Mercurialis-like plants which Bentham (1880) Pax and K. Hoffmann as well as (1914, 1931) enumerated close

together with Mercurialis. This relationship, however, is not confirmed by pollen-morphological results.

Leidesia procumbens (Linn.) Prain Leidesia type.

P = E = P:E = Splitgerber [L] PI. XIX, 1 19 ft 20,5 n 0,92. P.A.I. m:e < 0,5. = 0,3.

Microdesmis type

Tricolporate; spheroidal to oblate speroidal. In polar view pollen grains

convex triangular.

transversalis = Colpus isodiametric; m:e 1; ora large.

Colpi narrow; costae colpi broad and indistinct or absent. Tectate; psilate. Columellae short. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 89

The Microdesmis type is characterised by the isodiametric colpus and transversalis the large ora.

Taxonomic discussion

Bentham of this in (1880) discussed the genera type two tribes, Galearieae and Gelonieae. Microdesmis, Galearia and Pogonophora occurring in the Galearieae have characters both of the Phyllanthoideae and Crotonoideae. Pollen of these all grains genera are, however, not at comparable with those in the Phyllanthoideae. Pierre’s description being unknown to Pax (1899), he described Pierre in Centroplacus glaucinus Microdesmis as Microdesmis paniculata. Pax, however, did not have female flowers at his disposal. Pierre

(1899) and Gilg (1908), on the other hand, studied female material and had be found 2 ovules per locule, for which reason the plant to placed in the subfamily of the Phyllanthoideae. The structure of the male flowers, however, resembles that of Microdesmis to such an extent,

that it is by no means strange that Pax reckoned this species to Microdesmis. Since it is evident that the pollen grains of Centroplacus cannot be distinguished from those of Microdesmis, the correctness of the in the subtribe placing genus Antidesminae (Pax 1931) seems Two questionable. conclusions are possible:

link the 1. Centroplacus forms a between sub-family Phyllanthoideae and

Crotonoideae. On one side we find the characters that suggest a

close relationship to Microdesmis, while the Phyllanthoideae-

character of in stands the the two ovula per locule the ovary on other side.

2. Centroplacus has been described on the basis of material belonging is that to two species. The plant dioecious, so the possibility of

an erroneous combination of plants should not be overlooked.

A renewed accurate examination of the known material, will possibly remove the doubt.

Microdesmis subtype

Pollen small. Smaller than grains 20 fi. Costae colpi absent.

Microdesmis casearifolia Planch. Microdesmis subtype; oblate spheroidal.

Thorenaar T. 50 8 P = E = P:E = [U] PI. XIX, 15,5 // 17,5 ft 0,89.

P.A.I. = 0,3. Microdesmis zenkeri Pax Microdesmis subtype.

de 4 P = 18 E = 19 P:E = Wit [WAG] n // 0,95.

P.A.I. = 0,5. Centroplacus glaucinus Pierre Microdesmis subtype.

Tester 1922 [K] P = 14 E = 15,5 n P:E = 0,90.

Zenker 1761 [K] P.A.I. = 0,3.

Galearia dognaiensis Pierre ex Gagnep. Microdesmis subtype; suboblate.

Clemens 3528 P = E = P:E [U] 14,5 n 17,5 /u = 0,83.

P.A.I. = 0,35. Galearia filiformis (Blume) Pax Microdesmis subtype.

P = E = 19 P:E = 0,89. Blume, Java [U] 16,5 ft fi

P.A.I. = 0,3. 90 w. PUNT

Chaetocarpus subtype

Pollen than grains large. Larger 30 //. Costae colpi broad but indistinct.

Chaetocarpus castanocarpus (Roxb.) Chaetocarpus subtype; spheroidal.

ThWAITES P=E=29/< m:e ca. 1.

Elmer, Borneo 21064 [U] PI. XIX, 5 P.A.I. = 0,3. Chaetocarpus schomburgkianus (O. Kuntze) Chaetocarpus subtype.

Pax et K. Hoffm.

For. Dept. 2519 [U] Trigonopleura malayana J. D. Hook. Chaetocarpus subtype; oblate spheroidal.

Bosch Proefst. 83 E. IP. 1031 P = E = 38 P:E = [L] 35 n n 0,92.

PI. XX, 1 P.A.I. = 0,2. Pogonophora schomburgkiana Miers Chaetocarpus subtype; oblate spheroidal.

B. W. 6015 P = E = 45 P:E [U] 42 fi n = 0,93.

Krukoff 8645 [U] P.A.I. =0,4—0,45. Tectum perforatum.

Cheilosa type

Tricolporate; suboblate to oblate spheroidal. In polar view pollen grains

convex triangular.

Colpus transversalis; costae.

Colpi narrow; indistinct costae colpi.

Tectate; echinate or micro-echinate. Columellae short.

The Cheilosa the most characters of the type possesses important Mallotus configuration and is therefore placed in this configuration.

the the The type differs, however, distinctly by spines on tectum.

' ‘ ■ ■■ fn Cheilosa these than ' 'in Neoscortechinia spines are larger 1 pt (echinate);

smaller than 1 to the nomenclature of Faegri and /j.. According Iversen the pollen grains of Neoscortechinia are scabrate. The author

would like to call the small spines microechinate according to Erdtman in the of (1952). Echinate pollen grains are rarely found subfamily the Crotonoideae, only in the Croton configuration.

Taxonomic discussion

Bentham (1880) discussed Cheilosa in the Acalypheae, although the

male calyx is divided into slightly imbricate lobes. In the system of the is found in the tribe Pax and K. Hoffmann (1931) genus Gelonieae, which of to also Neoscortechinia belongs. The pollen grains both genera this is confirmed other are undoubtedly related. Unfortunately not by characters.

Cheilosa montana Blume Cheilosa type; suboblate.

9 P = E = P:E = Korthals, Java [L] PI. XX, 22,5 n 29/* 0,78.

m;e = 0,5. P.A.I. = 0,5-0,6. echinae 1-2 Echinate; ft. Neoscortechinia arborea (Elmer) Pax et Cheilosa type; oblate spheroidal.

K. Hoffm. P = E = P:E = 21y« 22,5 n 0,93.

Hort. Bogor. IX A. 6a. [U] PI. XX, 8 P.A.I. = 0,3. Scabrate (micro- echinate).

Claoxylon configuration

Tricolporate or stephanocolporate (4, rarely 5).

Colpi narrow. Tectate; capita of the columellae distinct. Pollen grains not reticulate. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 91

1. Athroandra plate xx. Trigonopleura malayana; 2. mannii; 3. Mercurialis annua; 4. 5. 6. Claoxylon cuneatum; Cladogynos orientalis; Cephalocrotonopsis socotrana; 7. Amperea xiphoclada; 8. Neoscortechinia arborea; 9. Cheilosa montana. 92 W. PUNT

The Claoxylon configuration is related to the Mallotus configuration.

The capita of the columellae, however, are distinctly visible.

Claoxylon type

oblate Tricolporate or stephanocolporate; spheroidal-prolate spheroidal. Colpus transversalis small; costae present but sometimes indistinct. absent Colpi narrow; costae colpi or indistinct.

Tectate; psilate or scabrate. Columellae coarse, capita distinct.

This type is in some characters comparable with types of the Mallotus configuration. The small spheroidal pollen grains resemble, in As in the Mallotus their shape, those of the Mareya type (p. 85). type (p. 79) more than three composite apertures can be present. Placing the type in the Bernardia configuration (p. 77) is out of question as a reticulum is always absent.

- - - - of the The Claoxylon' type is distinguished by the distinct capita columellae, which form a coarse and inordinate pattern.

Taxonomic discussion

all Genera belonging to this type are readily recognised by the shape and attachment of the anthers. Other corresponding characters are:

the 1. A disc present in female flowers.

2. In the male flowers an ovarium rudiment is always absent.

Usually an extrastaminal disc is also absent, but glands are

In inserted on the receptaculum. Discoclaoxylon receptaculum but in this extrastaminal disc is glands fails, genus an present.

3. Plants dioecious and in the Old World. are usually grow only

Erythrococca stolziana Pax et K. Hoffm. Claoxylon type; spheroidal.

Stolz 1556 P = E = 22 [U] n- m:e< 0,5. P.A.I. > 0,5.

Athroandra mannii (J. D. Hook.) Pax et Claoxylon. type; oblate spheroidal-sub- K. Hoffmann oblate. 5 (—4) colporate.

D. P = E P:E = [= Erythrococca mannii (J. Hook.) 30 n = 33,5 n 0,89. Prain] Mann 260 PI. XX 2 [U] ; Athroandra africana (Baill.) Pax et Claoxylon type; prolate spheroidal.

K. Hoffmann P = E=21 P:E = 22,5 ft ft 1,07. [= Erythrococca africana (Baill.) Prain] Zenker 453 [U]

Claoxylon cuneatum J. J. Smith Claoxylon type; spheroidal.

PI. 4 P E — Versteeg 1752 [U] XX, = 21 fi. Claoxylon tumidum J. J. Smith Claoxylon type; spheroidal. Versteeg 1708 [U] 3— (4) colporate.

P = E = 19 P.A.I. = /t. 0,4. Psilate to scabrate.

Micrococca mercurialis (Linn.) Benth. Claoxylon type; prolate spheroidal. D’Alleizette Mad. 1906 [L] 3- (4) colporate.

P = E = P:E = 27 n 25 n 1,08.

P.A.I. = 0,3. Discoclaoxylon hexandrum (Muell. Arg.) Claoxylon type; spheroidal.

P - E = 21 P.A.I. Pax et K. Hoffm. n- =0,3. Zenker 35 [U] POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 93

Mercurialis type

Tricolporate; subprolate to prolate. transversalis Colpus small; costae as long as the costae colpi. but Colpi narrow; costae colpi. Operculum present very narrow, consisting

of only one row of columellae. Tectate; psilate. Columellae distinct.

There is a certain relation between the Mercurialis type and the

Claoxylon type. The two types have distinct capita; both are not reticulate and small transversales. The Mercurialis possess colpi type - . .. . . the differs by presence of an operculum, which is narrow and in- distinct, and by the distinctly prolate shape of the pollen grains.

Taxonomic discussion

Shape and attachement of the anthers show much similarity with the of the For that Bentham genera Claoxylon group. reason (1880) placed Mercurialis in the immediate vicinity of Claoxylon, Erythrococca,

etc. Although the Mercurialis type differs somewhat from the Cloxylon

type, there is enough affinity for the author to share the opinion of Bentham.

Mercurialis annua Linn. Mercurialis type; subprolate.

Fresh Z.-Limb. PI. 3 P = E = P:E = material, XX, 25,5 y 22,5 y 1,16.

m:e < 0,5. P.A.I. = 0,4. Operculum of scattered indistinct, consisting some

pila on the endexine (membrana granulata). Mercurialis reverchonii Rouy Mercurialis type.

Faure P = E = P:E = 18-6-1931 [U] 28,5 /j. 22 /j. 1,30.

Mercurialis tomentosa Linn. Mercurialis type.

P = 40 E = P:E = Leeuwenberg 1317 [U] n 28,8 /i 1,40.

Cladogynos configuration

Tricolporate.

Colpi narrow; costae colpi. Tectate; columellae distinct. Exine thick.

The Cladogynos configuration includes those pollen grains with

distinct columellae that bear always a tectum or tectum perforatum.

These columellae can be arranged in a reticulum but more frequently form they do not a regular pattern. The pollen grains are usually the axis is at least 25 and often to 50 large; largest /i up (x.

Cladogynos type

Tricolporate; spheroidal prolate ( Epiprinus oblate spheroidal). Colpus transversalis; costae.

Colpi narrow; costae colpi.

Tectate or tectum perforatum. Columellae distinct. Exine thick. Some species intra-reticulate.

character The most striking of this type is the distinct, sometimes

even tall, columellae. The pollen grains are large and generally they

have a P:E larger than 1. 94 W. PUN'I

Taxonomic discussion

Pax and K. Hoffmann of this By (1914, 1931) most genera type in are placed the series Cladogyniformes of their subtribe Mercurialinae,

to which also Mallotus and Alchornea The be belong. group can

distinguished as follows:

in 1. An ovarium rudiment present the male flowers while a disc The is absent. few stamens are not inserted on a receptacle.

2. Male flowers usually in a capitule.

3. Anthers pendulous.

4. Stellate hairs always present.

5. Plants are monoecious and grow in the Old World.

orientalis Spanoghe Cladogynos Zipp ex Cladogynos type; prolate spheroidal.

Pierre PI. 5 P = E = 40 = 6213 [L] XX, 42/i /r P:E 1,05.

Colpus transversalis narrow. Tectum

perforatum. P.A.I. = 0,3. Intra-reti- lumina 1-2 culate; /s.

Cephalocroton cordofanus Hochst. Cladogynos type; subprolate.

D’Alleizette 1909 P = 49 E = 42 P;E = Nubie, Aug. [L] n p 1,17.

Colpus transversalis broad; m:e >0,5. Intra-reticulate. P.A.I. = 0,3. Pax Cephalocrotonopsis socotrana (Bale, f.) Cladogynos type; prolate spheroidal.

594 PI. 6 P = 46 E = P:E Schweinfurth [K] XX, 42,5 fi = 1,09.

P.A.I. = 0,25. Intra-reticulate.

Symphyllia siletiana Baill. Cladogynos type; prolate spheroidal.

Hort. Cult. P = 27 E = 25 P;E = Bog. [L] ii n 1,07.

P.A.I. = 0,25-0,3. Not reticulate. Adenochlaena leucocephala Baill. Cladogynos type; prolate spheroidal.

= Hildebrandt 3258b P 53 P:E = [L] /u E=48/< 1,10.

m:e = 0,4. P.A.I. = 0,3.

Not reticulate.

Epiprinns poilanei Gagnep. Cladogynos type; oblate spheroidal.

Clemens P = E = 35 P:E 3058 [U] 32 ft n — 0,91.

P.A.I. == 0,2-0,25. Not reticulate.

Amperea type

Dicolporate or tricolporate. Shape differs with the number of colpi from oblate spheroidal (dicolporate) to prolate spheroidal (tricolporate). transversalis Colpus narrow; costae. and P.A.I. Colpi narrow long; costae colpi. small to 0.

Tectate; psilate. Exine thick. Intrareticulate or not reticulate.

The shows much with the Amperea-type similarity Cladogynos t>T)e - T-. The Especially the thick exine and the tall columellae are striking. is much smaller. Some P.A.I., however, pollen grains are even syn- colpate.

Taxonomic discussion

those Australian that Amperea belongs to genera, were kept separate of their Should this on account narrow cotyles (Stenolobae). group as such be abolished, then, according to the statement of Pax (1924),

has this genus to be placed in the Mercurialinae. This group also the of the comprises genera Cladogynos type. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 95

Amperea xiphoclada (Sieb. et Spreno.) Amperea type.

Druce 2- P:E = 0,90.

Constable 26475 [U] PI. XX, 7 3- P:E = 1,02.

P = E = 27-29 ft 28-30 fi.

P.A.I. = 0,15-0. m:e < 0,5.

Not reticulate.

Amperea spartioides Brongn. Amperea type; spheroidal.

Tasmania P = E = [U] 26 ft. Intra-reticulate.

Pseudocroton type

Tricolporate; prolate spheroidal to subprolate. Colpus transversalis; costae? col Colpi narrow; costae pi? Tectate; psilate. Not reticulate.

The of pollen grains the sheet examined were not mature, so it is difficult them in the There is to put proper type. some resemblance with the Speranskia type (p. 75). A reticulum, however, is absent. As distinct columellae it in are present, seems best to place this type the Cladogynos configuration.

Taxonomic discussion

Bentham Pax K. (1880) as well as et Hoffmann (1931) discuss the Pseudocroton in Chrozophoreae. They accept relationship with

Argythamnia and its allies. The pollen grains have some affinity with the the Speranskia type. Although genera of this type belong to the in Chrozophoreae, they are only found the Old World, while Pseudocroton

in Central America. Affinities with the grows genera of Cladogynos

configuration are few.

Pseudocroton tinctorius Muell. Arg. Pseudocroton type. O. Kuntze 1808 Too [K] young to give reliable measures.

Hippomane configuration

Tricolporate; pollen grains in polar view circular or three-lobed.

Never convex triangular or triangular.

Colpus transversalis frequently short; sometimes narrow elongated.

A is Colpi narrow; usually long. margo nearly always present.

Intectate or more often tectate. Columellae distinct, frequendy large.

It is not possible to define this configuration with one or two exceptionless characters. The pollen grains are, however, easily The recognised by a combination of several typical characters. most important ones are: three-lobed polar view; margo; distinct, sometimes and If large, columellae short colpi transversales. one of these striking characters is absent the combination of the others still places the pollen grains immediately in this configuration.

Taxonomic discussion

The of this be divided into genera configuration can two groups. The first of the tribe of Pax group comprises genera Hippomaneae and K. Hoffmann (1912b, 1931). In 1880, Bentham stated of his subtribe 96 W. PUNT

“This of the Hippomaneae: is one most natural subtribes of Crotoneae”.

Indeed there is of close not any doubt a relationship between the genera.

Pachystroma is added to the first group. Evidently on technical

~ Bentham added the of grounds Pachystroma to group the Adrianeae with Adriana Manihot, and Cephalocroton, three genera now placed in three different of Pax and K. Hoffmann groups plants. (1919d, 1931) separated the monotypic genus into the tribe Pachystromateae, although they were aware of some affinity with the Hippomaneae. The well-

of the is in developed calyx male flower, which never present the led them the decision the Hippomaneae, to to separate genus. There are, characters of fusion than however, more in favour a of a separation. the in Pollen morphology is one of data favour of fusing. The second includes all the of the with group genera Euphorbieae the addition of Hura. It is remarkable that the typical Euphorbieae, so well characterised their which by cyathium, possess pollen grains can hardly separated from those of the Hippomaneae. Pax (1924) when

“ discussing the phylogenetic relations of the Euphorbiaceae, pointed already to this relationship. He noticed, e.g., the unbranched laticife- vessels which both Pollen rous taxa possess. morphology is another character to support the opinion of Pax.

Hippomane type

Tricolporate; shape differs from subprolate to suboblate. Pollen grains in

polar view circular or three-lobed. Colpus transversalis small (rarely elongated); costae.

Colpi narrow and costae colpi. Usually long; margo present .

P.A.I. is small (smaller 0,3) except in some species of Mabea. Tectate; psilate. Columellae sometimes tall.

The differs from the Hippomane type Euphorbia hirta type by its is narrower margo. Usually the margo narrower than the colpus In transversalis. other respects both types can hardly be separated. Pollen of grains the Omalanthus nutans subtype can be separated from the Hippomane subtype by the deeply three-lobed pollen grains. Some species in the Hippomane type have an intra-reticulum. They do not to the Dichostema the belong altogether type (p. 100) as upper the columellaeis in all thus part of fused directions, forming a tectum.

Hippomane subtype

Pollen grains in polar view circular or slightly three-lobed.

Hippomane mancinella Linn. Hippomane subtype; prolate spheroidal.

= = 1856 PI. 3 P E P:E = Buysman [U] XXI, 32,5 /j. 30,5 n 1,06.

m:e < 0,5. P.A.I. = 0,25. Omalanthus populneus (Geisel) Pax Hippomane subtype.

Docters v. Leeuwen 1716 [U] P = 40 fi E=34/i P:E = 1,17.

P.A.I. = 0,15-0,20. Mabea piriri Aube. Hippomane subtype.

B. W. P = 50 E = 44 P:E 6296 [U] ju n = 1,14. P.A.I. = 0,20-0,25. Not reticulate. Mabea taquari Aubl. Hippomane subtype.

Pulle 67 P = E = 41 P:E = [U] 43,5 fi n 1,05. P.A.I. = 0,4. Intra-reticulate. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 97

Mabea caudata Pax et K. Hoffm. Hippomane subtype.

v. Emden 18-9-1931 P = E = 70 P.A.I. = [U] p. 0,4-0,3. Not reticulate. Mabea fistulifera Mart. Hippomane subtype.

Y. Mexia 4473 = = [U] P E 70 /i. P.A.I. = 0,3. Indistinct intra-reticulate. Tectum perforatum. Actinostemon lanceolatus Saldanha Hippomane subtype; oblate spheroidal. '

Y. Mexia 4987 P = E = 35 P:E = [U] 33,5 n n 0,94.

P.A.I. = 0,25. Margo absent. Costae indistinct.

Gymnanthes lucida Swartz Hippomane subtype; oblate spheroidal.

Hohsle P = E = 26 P:E Jamaica, [U] 25 n n = 0,96.

P.A.I. = 0,25. Margo absent. Colu- mellae short.

Glyphostylus laoticus Gagnep. Hippomane subtype.

Lakshnaka = 1352 P E = P:E = [K] 36,5 n 34,5 /x 1,06.

P.A.I. = 0,25. Colpus transversalis elongated. Columellae tall. Spirostachys venenifera (Pax) Pax Hippomane subtype.

Excoecaria P = 22 E = 23 P:E = [= venenifera Pax] n n 0,96. Graham 1464 PI. 3 P.A.I. [K] XXIII, = 0,25. Margo absent. Excoecaria bicolor Hassk. Hippomane subtype.

Hort. IX C. 77 PI. 4 P = 38 E = 36 P:E = Bogor. [U] XXII, n ft 1,05. P.A.I. = 0,25. Pax K. Hoffm. Stillingia gymnogyna et Hippomane subtype.

1351 = P E = 33 P:E = Wiggins [U] 35,5 /u fi 1,08.

P.A.I. = 0,2. Sapium longifolium (Muell. Arg.) Huber Hippomane subtype. Pedersen 72 P = 55 E = 43 P:E = [U] n n 1,26.

P.A.I. = 0,25. Colpus transversalis Costae elongated. equatoriales or almost equatorial. Colliguaya integerrima Gill, et Hook. Hippomane subtype.

Donat 167 P = E = 34 P:E [U] 35,5 fi n == 1,04.

P.A.I. = 0,2. Margo indistinct;

narrow.

Omalanthus nutans subtype

Pollen grains in polar view distinctly three-lobed.

Omalanthus nutans (Forst.) Pax Omalanthus nutans subtype.

Yuncker 15356 [U] PI. XXI, 8 P = 35 n E — 31,5 fi P:E = 1,11.

P.A.I. = 0,15. Mabea indorum Sp. Moore Omalanthus nutans subtype.

1084 P = 45 E = P:E = Krukoff [U] n 36,5 n 1,22. P.A.I. = 0,2-0,25. Actinostemon concolor (Spreng.) Muell. Omalanthus nutans subtype.

P = 30 E = 34 P:E = n /t 0,88. Bornmueller 536 [U] PI. XXII, 3 Columellae short. Gymnanthes jamaicensis (Britten) Urban Omalanthus nutans subtype.

Harris 10936 P = E = 22 absent. [U] ft. Margo Sebastianiachamaelea (Linn.) Muell. Arg. Omalanthus nutans subtype.

Hohenacker 830 [U] P = 33/< P;E = 1,14.

P.A.I. = 0,2. Sebastiania corniculata(Vahl) Muell. Arg. Omalanthus nutans subtype.

Frees 11761 P = E = 40 P.A.I. = [U] n- 0,15-0,2. Macguire and Stahel 22758 [U] Sebastiania scottiana Muell. Arg. Omalanthus nutans subtype.

Bertoni 1714 P = E = 27 P.A.I. [U] n. = 0,2. 98 W. PUNT

platexxi. 1. Stenadenium spinescens; 2. Elaeophorbia drupifera; 3. Hippomane mancinella; 4. Dichostema glaucescens; 5. Pachystroma longifolium; 6. Senefeldera macrophylla; 7. Tetra-

plandra gibbosa; 8. Omalanthus nutans. pollen morphologyof the euphorbiaceae 99

Duvigneaudia inopinata (Prain) Leonard Omalanthus nutans subtype.

Zenker P = E = = 217 [U] 23 /j. 20 /i P:E 1,16.

P.A.I. = 0,2. Maprounea brasiliensis St.-Hill. Omalanthus nutans subtype.

Williamson-Assis 8047 P = E = P:E = [U] 33,5 /j. 30,5 n 1,11. P.A.I. = 0,2. Maprounea guyanensis Aubl. Omalanthus nutans subtype.

B. W. 5393 P = 24 E = 20 P:E = [U] n n 1,20. P.A.I. = 0,2. Excoecaria philippinensis Merrill Omalanthus nutans subtype.

Palawan 13124 P = E P.A.I. Elmer, [U] 32/* = 32/i. = 0,2-0,25. Sapium ellipticum (Hochst.) Pax Omalanthus nutans subtype.

Croockewit 728 [WAG] P = E = 30 n. P.A.I. = 0,2.

Stolz P = 40 E = 34 P:E 621 [U] n = 1,18. Sapium sebiferum (Linn.) Roxb. Omalanthus nutans subtype.

Lilnee, Japan [U] P = 46 p. Sapium aubletianum (Muell. Arg.) Huber Omalanthus nutans subtype. 46 B. W. P = 2141 [U] p.

Sapium montanum Lanj. Omalanthus nutans subtype.

B. W. 5889 P = 52 [U] p. Sapium klotzschianum (Muell. Arg.) Omalanthus nutans subtype.

Huber P = 54 p. Slabel, Oct. 1944 [U] Grimmeodendroneglandulosum (A. Rich.) Omalanthus nutans subtype.

Urban P = 28 E = 26 P:E = fi n 1,08.

Curtiss 190 [K] P.A.I. =0,2. Colpus transversalis

narrow elongated. Bonania cubana A. Rich. Omalanthus nutans subtype (?).

Howard 5774 P = 27 E = P:E = [U] /z 25,5 p 1,06.

P.A.I. = 0,2. Bonania domingensis (Urb.) Urb. Omalanthus nutans subtype.

Fuertes 813 B = E P.A.I. [U] 22 p = 22 n. = 0,25. Columellae small.

Adenopeltis colliguaya Bert, ex Juss. Omalanthus nutans subtype.

Andreas P = E = P:E = 834 [U] 34,5 n 33,5 n 1,03.

P.A.I. =0,15. Intra-reticulate. Dalembertia populifolia Baill. Omalanthus nutans subtype. Hinton 4353 = = = [K] P 41 E 36 n P:E 1,12.

P.A.I. = 0,15-0,2. Intra-reticulate. Tetraplandra gibbosa Pax et K. Hoffm. Omalanthus nutans subtype.

Glaziou 5613 P = 30 E = P:E = [K] PI. XXI, 7 n 27 n 1,11.

P.A.I. = 0,15. Ophthalmoblapton macrophyllum F. Allem. Omalanthus nutans subtype.

P E = 39 P:E Glaziou 17752 [K] = 42 n /i = 1,08.

P.A.I. = 0,2. Algernonia brasiliensis Baill. Omalanthus nutans subtype. H. F. Hance 1887 [K] Young.

Pachystroma type

Tricolporate; spheroidal. Pollen grains slightly three-lobed. Colpus transversalis broad elliptic; costae thick. and No Colpi narrow short; costae colpi. margo present. Tectate; psilate.

Pollen grains of this type are strongly related to those of the

Hippomane type. The colpus transversalis, however, is broadly elliptic and the P.A.I. is much larger. 100 w. PUNT

Pachystroma longifolium (Nees) Pachystroma type.

I. M. P = 41 E = 41 P:E 1. Johnston n ft ca. Krug and Urban 1367 [L] PI. XXI, 5 Length of colpi differs; mostly short, sometimes long. Costae thick.

hirta Euphorbia type

Tricolporate; subprolate to oblate spheroidal. Pollen grains in polar view three-lobed.

Colpus transversalis; costae. broad. is Colpi narrow; margo Sometimes an operculum present. Tectate; psilate. Columellae distinct.

be The pollen grains belonging to this type can hardly separated

from the Hippomane type. The margo is broader; mostly as broad If in as the colpus transversalis. The colpi are narrow. the future more

will Euphorbiaceae species are examined pollen-morphologically, it

be combine the perhaps necessary to two types.

Euphorbia hirta subtype

Pollen grains without an operculum.

Euphorbia hirta Linn. Euphorbia hirta subtype; subprolate.

20 H P = 30 E = P:E = Soeprata [U] /x 23 n 1,30.

P.A.I. = 0,10. Euphorbia peplus Linn. Euphorbia hirta subtype. Oblate Fresh material, Utrecht. spheroidal.

P = E = P:E = 26,5 p 28,5 p 0,93.

P.A.I. = 0,25. Euphorbia palustris Linn. Euphorbia hirta subtype. Prolate Fresh material, Hortus Utrecht. spheroidal.

= P = 50 n E 45 n P:E = 1,10. P.A.I. = 0,3. Diplocyathium capitata (Reichb.) Euphorbia hirtasubtype; oblate spheroidal.

H. Schmidt P = 31,5 fi E = 34,5 fi P:E = 0,91.

Baldacci, Aug. 1891 [BR] P.A.I. = 0,2.

Euphorbia esula subtype

Pollen grains with an operculum.

This subtype differs from the other pollen grains in the Euphorbia hirta type by its opercolum.

Euphorbia esula Linn. Euphorbia esula subtype. Oblate spheroidal.

Utrecht. P = 43 E = 40 P:E = Fresh material, n n 0,93.

P.A.I. = 0,2.

Dichostema type

Tricolporate; oblate spheroidal. Pollen grains in polar view circular to three-

lobed.

Colpus transversalis; costae. small absent. Colpi narrow; margo or Intectate; reticulate. Columellae large. Exine thick.

from other The Dichostema type is differentiated the types by its The columellae fused distinct reticulum and narrow margo. are in and form reticulum. The laterally their upper part a tigillate pollen grains have a thick exine.

Dichostema glaucescens Pierre Dichostema type; oblate spheroidal-sub- Klaine 1129 [L] PI. XXI, 4 oblate.

P = 31 /a E = 36 P;E = 0,87.

m:e=0,5. P.A.I.=0,3. Lumina 1-3 ft. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 101

Anthostema aubryanum A. de Juss. Dichostema type; oblate spheroidal.

1074 P = 29 E = P:E = Spuitebanto [U] n 31,5 n 0,92. Lumina 1-2 u.

Senefeldera macrophylla Ducke Dichostema type; spheroidal,

For. 7549 PI. 6 p = E = 36 P.A.I. = Dept. [U] XXI, ft. 0,2-0,25.

Lumina 2-3 fx.

Euphorbia cotinoides Miquel Dichostema type; prolate spheroidal.

1635 = 28 E = 26 P:E = Ellenberg [U] P /i n 1,08. Stahel = and Gongryp 816 [U] m:e 0,5. P.A.I. - 0,25. Margo ab- Lumina 2-3 sent; /x.

Stenadenium type

Tricolporate; subprolate. Pollen grains large. Colpus transversal is broad and elongated; costae. Colpi narrow and long; costae colpi indistinct. Margo absent. Tectate; psilate; not reticulate. Columellae distinct but small in diameter. Exine relatively thin.

than and Pollen grains of this type are large (larger 40 /a) have a relatively thin exine. The columellae are slender; their diameter is small. In polar view the pollen grains are not distinctly three-lobed.

A margo is absent. The of Hura have shorter pollen grains crepitans a colpus transversalis The than those of Stenadenium and Synadenium. shape and structure, however, are similar.

Stenadenium spinescens Pax Stenadenium type; subprolate.

Goetze 1099 [BM] PI. XXI, 1 P = 59 n E = 47 n P:E = 1,26. Staff Stenadenium Elaeophorbia drupifera (Thonn.) type.

P = 58 E = 50 P:E Leeuwenberg 2314 [U] PI. XXI, 2 fx n = 1,16.

P.A.I. = 0,2. Tectum perforatum. Hura crepitans Linn. Stenadenium type.

B. W. 694 P = 75 E 63 P:E = [U] n = fi 1,20.

B.B.S. 502 [U] PI. XXII, 2 P.A.I. = 0,4.

Synadenium arborescens Boiss. Stenadenium type. Y D’Alleizette, Medley 8492 [L] oung.

Pedilanthus type

Tricolpate; oblate spheroidal to suboblate. Pollen grains slightly three-lobed. broad. Membrana Colpi Margo narrow. granulata. Intectate (tectum perforatum?); psilate. Columellae tall.

Pedilanthus differs from other types in the Hippomane configuration the P.A.I. is by the absence of a colpus transversalis. Also somewhat larger.

Pedilanthus palmeri Millsp. Pedilanthus type.

Hinton 15793 = PI. 1 P 72 E = 83 P:E = [U] XXII, n n 0,87.

P.A.I. = 0,3.

Pollen grains not placed in one of the Crotonoideae con-

figurations

Dalechampia type

Tricolporate; Pollen grains large, usually prolate to prolate spheroidal. Colpus transversalis elongated. Sometimes costae quatoriales.

Colpi short and narrow. No costae colpi present. intra-reticulate. Reticulum Between Tectate; very coarse. the muri of the reticulum a membrane is present, covering the lumina. 102 W. PUNT

platexxii. 1. Pedilanthus palmeri;Ex-2. Hura crepitans; 3. Actinostemon concolor; 4. coecaria bicolor. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 103

Thetype is characterised by its large pollen grains and wide lumened reticulum. The pollen grains are so typical, that no other type can be compared with them.

Taxonomic discussion

Dalechampia is easily distinguished from other genera by its typical For Mueller in involucre. this reason (1866) placed it the vicinity of the Euphorbieae. Bentham (1880) pointed to the similar characters in the Plukenetieae hairs and thickened : e.g. climbing growth, stinging style in the female flowers. Pax and K. Hoffmann (1919) thought

it better to the into tribe. Croizat separate genus an apart (1940a)

~ and Hurusawa (1954) once again placed the genus near Euphorbia and its allies.

Pollen grains show a typical structure and are neither comparable in the with the types Plukenetinae nor with those in the Euphorbieae. Pax and K. Hoffmann’s classification the in maintaining genus far the a separate tribus not too from Plukenetinae seems the best opinion.

Dalechampia dioscoreifolia Poepp. et Dalechampia type; prolate. Endlich. 105 P = E = 70 P:E n n = 1,50. G. 4186 PI. 6 Lumina Costae Klug [U] XXIII, up to 12 ft. equatoriales. Muell. Dalechampia affinis Arg. Dalechampia type; prolate spheroidal.

B. W. P = 105 E = = 2183 [U] fi 97 fi P;E 1,08. Costae equatoriales.

Dalechampia brasiliensis Lam. Dalechampia type; prolate spheroidal.

Y. Mexia 5270 P = 57 E 55 P:E = [U] fi = n 1,04. Costae equatoriales. Dalechampia scandens Linn. Dalechampia type; oblate spheroidal.

Forest. P = 105 E Serv. 4328 = 75 P:E = [U] n n 1,40. Costae equatoriales. Dalechampia spathulata (Scheidw.) Baill. Dalechampia type; oblate spheroidal.

Fresh material, Hort. Utrecht. P = 6‘3yu E=65|< P:E = 0,97.

PI. XXIII, 5 Costae transversales; m:e = 0,5.

Hamilcoa type

Tricolporate; suboblate. In polar view the pollen grains circular to slightly

convex triangular.

Colpus transversalis narrow.

Colpi narrow and short; indistinct costae colpi. Tectate (?); intra-reticulumfine or not reticulate; columellaedistinct but small.

The Hamilcoa type cannot be placed in one of the discussed con- figurations. The pollen grains have columellae with small but distinct

capita and are for that reason excepted from the Mallotus configura- tion (p. 77). The structure of Hamilcoa would be in better agreement with the Claoxylon configuration, (p. 90), but the related pollen grains of and Pimeleodendron the Plagiostyles are reticulate; moreover, polar view differs. Perhaps the Moultonianthus type in the Bernardia con- is of figuration (p. 73) most related to the Hamilcoa type because its and fine reticulum in circular polar view present some species. As the position of this type is still uncertain the author prefers from all other to keep it apart configurations. 104 W. PUNT

plate xxiii. I. Plagiostyles africana; 2. Pimeleodendron zoanthogyne; 3. Spirostachys venenifera; 4. Hamilcoa zenkeri; 5. Dalechampia spathulata; 6. Dalechampia dioscoreifolia. POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 105

Taxonomic discussion

Prain (1913) thought Hamilcoa was nearest related to Plagiostyles Pierre and Pimeleodendron Hasskarl. Pax and K. Hoffmann (1912b, 1931) agreed with the relationship of Plagiostyles and Pimeleodendron, which both in the Hamilcoa, however, was they placed Hippomaneae...... In transferred to the Gelonieae. doing so they rejected the affinity between Hamilcoa and Plagiostyles. The three have several characters in genera common:

1. Disc absent in male as well as in female flowers.

2. In male flowers an ovarium rudiment is absent. Filaments are

short very or wanting.

3. Pedicels are thickened.

4. Styles are undivided. 5. Plants dioecious (In Hippomaneae usually monoecious).

in the in the Sumbavia Perhaps Nealchornea, present paper placed configuration (p. 69), is also related to Hamilcoa and its allies.

Hamilcoa zenkeri (Pax) Prain Hamilcoa type; suboblate to oblate Zenker 4765 [L] PI. XXIII, 4 spheroidal.

= P E = P:E = 23,5 n 27 0,87. P.A.I. Lumina 1 m: e < 0,5. > 0,5. ca. /i.

Pimeleodendron zoanthogyne J. J. Smith Hamilcoa type; spheroidal.

Hallier 152a P = E = 24 P.A.I. = [U] PI. XXIII, 2 fi. m:e ca. 1. 0,5-0,6. Not reticulate.

Plagiostyles africana (Muell. Arg.) Prain Hamilcoa type; oblate spheroidal.

Zenker 94 PI. I P=27 E = P:E = [U] XXIII, /* 29yit 0,90.

m:eca. 1. P.A.I. = 0,4. Costae colpi.

Taxonomic comment on the Crotonoideae

The subfamily of the Crotonoideae includes a large number of pollen types.

The types with a croton-pattern attract most attention. When in the future of the will a revision Crotonoideae be undertaken, the

placing of all genera with a croton-pattern into one group will be

advisable. This will benefit a natural classification of the subfamily.

The relationship of, e.g., Joannesia with Cunuria and Garcia with

in this show better than it does at Sagotia will, way, to advantage

present in Pax and K. Hoffmann’s system. Two other of the Cnesmosa groups well-distinguished pollen grains, found in the sub- configuration and the Plukenetia configuration, are

tribe Plukenetiinae. Omphalea is added to the Plukenetia configuration, with Croizat which agrees the opinion of (p. 62). Mueller Arg., Bentham and Pax and K. Hoffmann include the tribe in their This tribe falls into Chrozophoreae systems. two groups of The first with pollen types. group e.g. Crotonogyne, Aleurites, etc. As possesses pollen grains with a croton-pattern. stated previously these should be from the other and transferred genera separated ones to the of which Croton is the The second group principal genus. group has with, e.g., Sumbavia, Chrozophora, Agrostistachys, aperturate pollen 106 W. PUNT grains, which belong to several pollen types. The present author would like to retain this second the subtribe group as Chrozophorinae. The tribe Acalypheae of Pax and K. Hoffmann includes most of the Crotonoideae. There few genera are, however, comparatively related Mallotus types which are, moreover, closely ( configuration, Bernardia configuration, etc.).

The tribes Gelonieae and Cluytieae, too, include genera of which the with mixed with pollen grains are provided a croton-pattern up of which the lack this structure. These latter genera pollen grains divisible into several A reclassification of these genera are types. tribes is badly needed.

Although Hippomaneae and Euphorbieae are both homogeneous taxa which are taxonomically well-defined, the morphology of the pollen little difference between the Pax grains shows but two groups. (1924) already pointed out the relationship of these groups on other grounds.

Since the Hippomaneae are treated by all authors as a tribe of the

Crotonoideae, the Euphorbieae should also be treated as a tribe of the

Crotonoideae close to the Hippomaneae.

SUMMARY

In the present study pollen morphology of the Euphorbeaceae is treated as an additional character in taxonomy.

Besides the of the the ofPax K. Hoff- greaterpart genera occurring in system and

of the after 1931 studied. mann (1931), most genera published are

The pollen grains have been described with the aid of a terminology as simple as possible. In principle the terminology of Iversen and Troels-Smith has been

in of Erdtman have been used. followed, although addition, many improvements

One of the simplifications is the rejection of Potoni6’s term sculpture. All elements occurring on the endexine are called structure elements; all structure elements

form the of For the of endexine together structure a pollen grain. sake consequence

and extexine discussed apertures apertures are separately.

Different pollen grains are placed in different pollen types. If the differences are of minor importance, the pollen grains are placed in subtypes. Several types can

the these have some characters in common. To express correspondences, types are

assembled in configurations.

As the in and Crotonoideae differ the division pollen types Phyllanthoideae distinctly, of the Euphorbiaceae in these subfamilies is maintained m the discussion ofthe results.

The be in three of Antidesma Phyllanthodieae can separated large groups pollen types (

Amanoa configuration, configuration and Aristogeitonia configuration), which agrees with the grouping of Pax in 1924. The remaining small configurations belong in taxonomic the of the respect to genera Antidesma configuration.

In the Crotonoideae many genera possess pollen grains with a croton-pattern.

These genera should be treated as a single group.

Besides this natural the Plukenetiinae which group, possess pollen grains are clearly

from other in the Pollen distinguished genera Crotonoideae. grains of Omphalea are similar to those in the Plukenetia configuration. This pollen-morphological result

with the of Croizat. agrees opinion POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 107

The in the less differentiate in remaining pollen grains Crotonoideae are easy to

One of the is the Mallotus which groups. largest configurations configuration,

of the other tribes. The includes most genera Acalypheae and several genera or

Hippomane configuration is another large one. This configuration comprises the tribes The of both tribes Hippomaneae and Euphorbieae. pollen grains are very similar. The is well genus Pachyslroma pollen-morphologically as as taxonomically

related to the tribe Hippomaneae.

Per a. treated as a separate tribeby Pax and K. Hoffmann, is related by its pollen

in the grains to some genera Acalypheae.

is related the in the Plukenetiinae. Pollen- Dalechampia habitually to genera

do this relation. The of morphological data, however, not support pollen grains

similar other Dalechampia are not to any pollen type.

is in the The morphology of the pollen grains of the Stenolobeae agreement with

of these Australian is artificial opinion of Pax, that any separation genera an one.

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Euphorbiaceae-Cluytieae. 124 pp.

—— In Das Pflanzenreich IV. 147 and . 1912a. Engler, (4): 41 Euphorbiaceae-Gelonieae. pp.

— and . 1912b. In Engler, Das Pflanzenreich IV. 147 (5): 319 Euphorbiaceae-Hippomaneae. pp. and In Pflanzenreich . 1912c. Engler, Das IV. 147 (6): 142 Euphorbiaceae-Acalypheae-Chrozophorinae. pp.

and 1914. In Das Pflanzenreich IV. 147 . Engler, (7):

Euphorbiaceae-Acalypheae-Mercurialinae. 473 pp. and 1919a. In Das 147 . Engler, Pflanzenreich IV. (9-11): Euphorbiaceae-Acalypheae-Plukenetinae, Epiprininae, Ricineae. 134

pp.

and 1919b. In Das Pflanzenreich IV. 147 —. Engler, (12):

Euphorbiaceae-Dalechampieae. 59 pp.

and 1919c. In Das Pflanzenreich IV. 147 . Engler, (13): 13 Euphorbiaceae-Pereae. pp. 1 In Das Pflanzenreich 147 and . 919d. Engler, IV. (14):

Euphorbiaceae-Additamentum. 231 pp.

— In Das Pflanzenreich IV. 147 and -. 1922. Engler, (15):

349 Euphorbiaceae-Phyllanthoideae-Phyllantheae. pp. and In Das Pflanzenreich IV. 147 . 1924. Engler, (16):

Euphorbiaceae-Crotonoideae-Acalypheae-Acalyphinae. 231 pp. In and Die Pflanzen- and . Engler Harms, Naturlichen

familien. ed. 2. 19c: 11-233.

Phillips, E. 1943. Some changes in nomenclature. Journ. S. Air. Bot. 9: 137-140. L. 1899. Bull. Soc. Linn. Paris 2: 114. Pierre, Centroplacus glaucinus. ser. Forhandl. Post, L. v. 1918. Skogstradspollen i sydsvenska torfmosselagerfoldjer. 16. Skand. Naturforskermote 1916. Potonie, R. 1934. Zur Morphologic der fossilen Pollen und Sporen. Arb. Inst. Palaeobot. und Petrogr. Brennsteine 4: 5-25, 109.

Sandwith, N. Y. 1950. On two Euphorbiaceae of British Guiana. Kew Bull. 1950:

133-136.

R. E. 1952. Studies in the Micrandra Bot. Mus. Leaf!. Harv. Schultes, genus 1. Univ. 15: 201-224.

1955. A new in the Bot. Mus. Leaf!. . generic concept Euphorbiaceae.

Harv. Univ. 17: 27-36.

Smith, J. J. 1910. In S. H. Reorders en Th. Valeton, Boomsoorten van Java 12: 9-638.

G. G. 1948. Note the Moultonianthus Merr. Steenis, C. J. v. on genus (Euph.).

Bull. Bot. Card. Buitenzorg ser. 3. 17: 404—405.

V. B. A. 1848. Cocotale. Padova, 99. Trevisan, Alghe p. Webster, G. L. 1956-1958. A monographic study of the West Indian species of Phyllanthus. Journ. Arnold Arb. 37, 38 and 39. Wodehouse, R. P. 1928. The phylogenetic value of pollen-grain characters. Ann.

Bot. 42: 891-934.

Pollen New York. 574 . 1935. grains. pp. Zinderen E. M. 1953. South African I. Barker, van. pollen grains and spores

Amsterdam (Cape Town) 88 pp. INDEX

(Asterisks indicate illustrations)

* Acalypha type, 79, 81 xiphoclada, 95 Acalypha aronioides, 81 Amyrea humberti, 86 diversifolia, 81 Anabaena, 10

￿ indica, 81 Anabaenella, 10

racemosa, 81 tamnoides, 63 platyphylla, 81 Anabaina, 10

* scandens, 81 Andrachne subtype, 28 6 Acalyphopsis, Andrachne aspera, 29 Acidocroton adelioides, 51 colchica, 29

* Acidoton urens, 57 phyllanthoides, 29

* Acephila excelsa, 29, 32 telephioides. 29 Actephilopsis malayana, 60 * Androstachys johnsonii, 43 , .

‘ ￿ Actinostemon concolor, 97 Angostyles longifolia, 63 lanceolatus, 97 Annesijoa, 6 Adelia ricinella, 68 Anomalocalyx uleanus, 51 Adenochlaena leucocephala,. 94 Anthostema aubryanum, 101 Adenocline subtype, 48, 54 Antidesma configuration, 20, 30, 32, Adonocline, 48, 54 34, 39, 36, 43, 46 56 Antidesma acuta, type, 19, 20, 21, 26, 28 * mercurialis, 56 Antidesma subtype, 20, 21, 22, 24 99 Antidesma Adenopeltis colliguaya, agusanense, 22 Adenophaedra, 73 * bunius, 22 minor, 75, 82 diandrum, 22 prealtum, 82 edule, 22 Adriana, 96 ghesaembilla, 22 quadripartita, 80 membranaceum, 22 Agrostistachys, 105 obovatum, 22 76 indica, venosum, 22

* sessilifolia, 76 Aonikena patagonica, 66 Agyneia bacciformis, 39 * Aparisthmium cordatum, 83 Alchornea type, 19, 73, 79, 82, 83, 85 Apodandra, 62 Alchornea, 73, 75, 85, 94 buchtienii, 63 ilicifolia, 83 Apodiscus chevalieri, 22 laxiflora, 82 Aporosa, 25 82 rugosa, dioica, 24 schomburgkii, 82 frutescens, 24 * triplinervia, 82 lindleyana, 24 * villosa, 82 Aporosella, 25 Alchorneopsis, 85 * Arachnodes, 38 floribunda, 86 chevalieri, 40 86 trimera, Argythamnia type, 68 Aleurites, 105 Argythamnia, 66 moluccana, 50 * candicans, 266, 68 Algernonia brasiliensis, 99 * Argomuellera macrophylla, 76 Alphandia furfuracea,.50 Aristogeitonia configuration, 40, 46 Amanoa 46 40 configuration, 32, 36, 38, Aristogeitonia type, Amanoa type, 32, 33, 34 Aristogeitonia subtype, 41 Amanoa, 19, 32, 33 Aristogeitonia limoniifolia, 41 boiviniana, 33 Astrocasia, 25, 32 bracteosa, 33 tremula, 26 grandiflora, 33 Astrococcus, 62

* * guianensis, 33 cornutus, 63 ￿ oblongifolia, 33 Athroandra africana, 92

* Amperea type, 19, 94 mannii, 92

Amperea spartioides, 95 Avellanita bustillosii, 80 POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 111

Baccaurea subtype, 21, 22, 24 Cenesmon, 10, 57 Baccaurea javanica, 24 Centroplacus glaucinus, 89 oxyxarpa, 24 Cephalocroton, 96

racemosa, 24 cordofanus, 94

* sumatrana, 24 * 94 Cephalocrolonopsis socotrana,, Baliospermum, 48 Cephalomappa configuration, 68

montanum, 51 Cephalomappa type, 68 Baloghia lucida, 51 Cephalomappa malloticarpa, 69 Benoistia, 48 Chaetocarpus subtype, 90

* perrieri, 51 Chaetocarpus castanocarpus, 90 Bemardia configuration, 73, 92, 103, schomburgkianus, 90

106 Cheilosa type, 79, 90 * Bernardia type, 73, 75, 76, 77 Cheilosa montana, 90 Bernardia, 85 Chiropetalum configuration, 62, 65 corensis, 75 Chiropetalum type, 65, 66, 68

75 66 lorentzii, Chiropetalum canescens, * pulchella, 75 * lanceolatum, 66 Bertya, 48 patagonica, 66 gummifera, 53 Chlamydojatropha, 6 Beyeria, 48 Chondrostylis bancana, 85 leschenaultii, 53 Chonocentrum, 21, 33 Bischofia type, 43 cyathoforum, 25 44 Bischofia, 9, 40, Chrozophora type, 69, 70, 72 ￿ javanica, 44 Chrozophora, 105 Blachia umbellata, 51 * plicata, 70 Blotia oblongifolia, 34 tinctoria, 70

Blumeodendron type, 79, 81 Cladogelonium, 48, 54 * Blumeodendron tokbrai, 81 * madagascariense, 54 Bocquillonia sessiliflora, 83 Cladogynos configuration, 69, 93 Bonania 99 cubana, Cladogynos type, 69, 93, 94 domingensis, 99 Cladogynos Botryophora geniculata, 81 * orientalis, 94 Breynia configuration, 38 Claoxylon configuration, 90, 103 Breynia type, 38, 39 Claoxylon type, 92, 93 38 * 92 Breynia subtype, Claoxylon cuneatum, Breynia, 29, 38, 39, 44 tumidum, 92

* fruticosa, 39 Claoxylopsis, 5 nivosa, 39 Clarorivinia, 6 39 racemosa, Cleidion, 82, 83 Breyniopsis subtype, 39 angustifolium, 80 * Breyniopsis Pierrei, 39 * javanicum, 80 Briedelia 36 type, 32, Cleistanthus, 32 Briedelia, 9, 32 dichotomus, 34 assamica, 36 * ferruginous, 36 glauca, 36 winkleri, 34 * 77 monoica, 36 Clutia type, 19, 75, stipularis, 36 Clutia abyssinica, 77 alaternoides, 77 Calpigyne hainanense, 86 natalensis, 77 Calicopeplus, 5 * paxii, 77 Caperonia type, 72 rubricaulis, 77 Caperonia subtype, 72 Cluytiandra madagascariensis, 34 Caperonia, 69 Cnesmosa configuration, 57, 58, 105 corchoroides, 72 Cnesmosa type, 57, 58 * palustris, 72 Cnesmosa, 10 serrata, 72 javanica, 57 Carumbium, 10 Cnidiscolus stimulosis, 53 72 Caryodendron type, urens, 53 Caryodendron grandifolius, 73 Coccoceras borneënse, 80 ￿ orinocense, 73 * Codiaeum variegatum, 51

Cavacoa aurea, 51 stellingianum, 51 112 W. PUNT

* Coelebogyne ilicifolia, 83 Ditaxis catamarcensis, 66 Coelodepas, 10 diversiflora, 66 Coelodiscus lanceolatus, 80 fasciculata, 66 Colliguaya integerrima, 97 * fendleri, 66 Cometia, 5 lancifolia, 66 Conveiba lutifolia, 83 salina, 66 simulata, 83 Ditta, 5 Conceveibastrum martianum, 83 Dodecastigma, 48 Cordemoya integrifolia, 80 amazonicum, 53 Corythea, 5 * Domohinea perrieri, 53 Croizatia, 5 Drypetes, 21, 44 Crotonoideae, 47 * glauca, 28 Croton configuration, 47, 58, 90 laterifolia, 28 58 Croton type, 48, 53, 54, 57, macrophylla, 28 Croton bahamensis, 50 variabilis, 28 * cuneatus, 50 Duvigneaudia inopinata, 99 hirtus, 50 Dysopsis configuration, 60 lingiradiatus, 50 Dysopsis type, 60 * matourensis, 47, 50 * Dysopsis glechomoides, 60 pullei, 50 Crotonogyne, 105 * Elaeophorbia drupifera, 101 parvifolia, 50 Elateriospermum, 48 preussii, 50 tapos, 51 Crotonogynopsis usambarica, 85 * Eleuterostigma lehmannianum, 62 Crotonopsis elliptica, 50 Endospermum, 48 Cunuria, 49 moluccanum, 54

spruceana var. bracteosa, 50, 53 Epiprinus poilanei, 94 Cyathogyne spathulifolia, 22 Eremocarpus, 48 viridis, 22 setigerus, 50 Cyrtogonone argentea, 50 Erismanthus type, 77 * * Cyttaranthus congolensis, 75, 76 Erismanthus indochinensis, 77 oblique, 77 101 Dalechampia type, Erythrococca africana, 92 Dalechampia affinis, 103 mannii, 92 brasiliensis, 103 stolziana, 92

* dioscoriifolia, 103 Euphorbia hirta type, 96, 100 scandens, 103 Euphorbia esula subtype, 100 * spathulata, 103 Euphorbia hirta subtype, 100 Dalembertia populifolia, 99 Euphorbia, 9, 103 Danguyodrypetes ambigua, 30 cotinoides, 101 Dendrophyllanthus type, 37 esula, 100 ￿ 37 hirta, 100 Dendrophyllanthus ripicolus, Deuteromallotus acuminatus, 80 palustris, 100 Deutzianthus tonkinensis, 50 peplus, 100 100 * Excoecaria 97 Dichostema type, 96, bicolor, * Dichostema glaucescens, 100 phillippinensis, 99 Dicoelia type, 20, 21, 28, 29, 32, 44 venenifera, 97 Dicoelia subtype, 28 Dicoelia affinis, 28 Flueggia, 25 Dimorphocalyx murina, 51 Fontainea pancheri, 51 Diplocyathium capitata, 100 Fragariopsis, 62

* Discocarpus type, 32, 36 scandens, 63 Discocarpus, 21 * essequeboensis, 36 Galearia dognaiensis, 89 hirtus, 34 filiformis, 89 Discoclaoxylon hexandrum, 92 Garcia, 48, 105 Discocleidion 83 50 type, 79, nutans, » Discocleidion rufescens, 85 Gatnaia annamica, 24 Discoglypremna caloneura, 76 Gavarretia terminalis, 83 * Dissiliaria tricornis, 41 Gitaria, 6

Ditaxis type, 65, 66, 68 Givotia rottleriformis, 51 POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 113

Glochidion type, 39 longifolium, 86 Glochidion, 29, 38, 44 * Kunstlerodendron sublanceolatum, 85 concolor, 39 littorale, 39 Lachnostylis hirta, 34 obscurum, 39 Lasiochlamys, 5 ramiflorum, 39 Lasiococca symphylliaefolia, 86

* sericeum, 39 Lasiocroton type, 65, 68 superbum, 39 * Lasiocroton macrophyllus, 68 Glycydendron amazonicum, 54 Lautembergia coriacea, 83 Glyphostylus laoticus, 97 multispicata, 83 Godefroya rotundata, 36 Leidesia type, 79, 88 Grimmeodendron eglandulosum, 99 Leidesia, 54, 60 Grossera major, 50 * procumbens, 88 Gymnanthes lucida, 97 Lepidoturus laxiflorus, 82 jamaicensis, 97 Leptonema type, 29

* Leptonema venosa, 29 Haematostemon guianensis, 63 * Leucocroton flavicans, 66 Hamilcoa 103 ￿ 30 type, Lingelsheimia frutescens, * Hamilcoa zenkeri, 105 Longetia buxoides subtype, 41 * Heterocalyx laoticus, 76 ￿ Longetia buxoides, 41

Hevea type, 48, 56 carunculata, 41 * Hevea brasiliensis, 56 gynotricha, 43 guianensis, 56 malayana, 41 Heywoodia type, 20, 30

* Heywoodia lucens, 30 Mabea caudata, 97 Hippomane configuration, 95 fistulifera, 97 100 97 Hippomane type, 19, 96, indorum, Hippomane subtype, 96 piriri, 96 * Hippomane mancinella, 96 taquari, 96 Holstia tenuifolia, 50 Macaranga densiflora, 80 Homalanthus, 10 harveyana, 80

￿ * Homonoia javensis, 86 spinosa, 80 riparia, 86 Maesobotrya dusenii, 22 Hura, 96 floribunda, 22 crepitans, 101 Mallotus configuration, 77, 90, 92,

* Hymenocardia type, 44 103, 106

Hymenocardia, 21, 44 Mallotus type, 19, 79, 81, 82, 85, 92 acida, 46 Mallotus subtype, 79, 80 ulmoides, 46 Mallotus, 70, 79, 94

* Hyaenanche globosa, 41 ￿ albus, 80 Hyeronima, 21 claoxyloides, 80 alchorneoides, 22 miquelianus, 80 * laxiflora, 22 repandus, 80 Manihot type, 47, 48, 53, 54 Jatropha, 53 Manihot, 53, 96 integerrima, 51 esculenta, 53 multifida, 51 saxicola, 47, 53

￿ panduraefolia, 3 Manniophyton fulvum, 50 Joannesia, 48, 105 Maprounea brasiliensis, 99 princeps, 51 guyanensis, 99

Julocroton argenteus, 50 Mareya type, 79, 83, 86, 92 triqueter, 50 ￿ Mareya brevipes, 85 Mareyopsis longifolia, 85 Keyodendron, 5 * Margaritaria nobilis, 26 Klaineanthus 56 Martretia 46 type, 47, 48, 54, type, * Klaineanthus subtype, 54 Martretia quadricornis, 46 Klaineanthus, 48, 54, 56 * Megistostigma peltatus, 57 * gaboniae, 54 ￿ malaccense, 57 Koilodepas, 10 ￿ Melanolepis multiglandulosa, 70 * bantamense, 86 Mercurialis type, 93 hainanense, 86 Mercurialis, 88 114 W. PUNT

* 93 annua, Paragelonium perrieri, 41 reverchonii, 93 Pausandra densiflora, 51 tomentosa, 93 morisiana, 51

Mettenia, 5 Pedilanthus type, 101 Micrandra, 47, 48, 50 * Pedilanthus palmeri, 101 brownsbergensis, 50, 54 Pentabrachion 34 o , reticulatum,

￿ . siphonioides, 50, 54 Pera type, 79, 86, 88 * Micrantheum ericoides, 43 Pera bicolor, 88 hexandrum, 43 glabrata, 88 Micrococca mercurialis, 92 Petalostigma quadriloculare, 41

Microdesmis type, 79, 88 Philyra subtype, 69, 72 Microdesmis subtype, 89 * Philyra brasiliensis, 72 * Microdesmis caseariaefolia, 89 Phyllanoa, 5 paniculata, 89 Phyllanthoideae, 20 zenkeri, 89 Phyllanthus nutans configuration, 37

Mildbraediapaniculata, 51 Phyllanthus acuminatus type, 43

Mischodon zeylanicus, 41 Phyllanthus nutans type, 37 Monadenium, 5 Phyllanthus acidus subtype, 20, 26 * Monotaxis grandiflora, 70 Phyllanthus niruri subtype, 24 „ . . Moultonianthus type, 19, 76, 103 Phyllanthus pentaphyllus subtype, Moultonianthus, 73, 75, 76 21, 24, 33, 77

* leembruggianus, 77 Phyllanthus, 18, 20, 21, 25, 29, 38, 77 26 acidus,, 25, ￿ Nealchornea type, 73 acuminatus, 43 Nealchornea, 105 acuminatissima, 26 * yapurensis, 73 adianthoides, 37

86 24 Necepsia afzelii, amarus, Neoboutonia, 47, 48 * capillaris, 26 macrocalyx, 51 discoideus, 26 Neomphalea, 6 * elsiae, 25, 26 Neopalissya castaneifolia, 85 guianensis, 25 Neoroepera banksii, 43 hyssopifolioides, 25 * Neoscortechinia arborea, 90 muellerianus, 26 Neotrewia cumingii, 83 * niruri, 25

* Neotrigonostemon, 6 nutans, 37 * Nephrostylus poilanei, 86 pentaphyllus, 24 reticulatus, 26 Oldfieldia, 44 stipulatus, 24 africana, 41 sublanatus, 24 Oligoceras, 48 speciosus, 37 eberhardtii, 50 urinaria 25

* Omalanthus nutans subtype, 19. 96, Pimeleodendron zoanthogyne, 105 97 Piranhea, 44 Omalanthus, 10 * trifoliata, 41 * 97 * 105 nutans, Plagiostyles africana, populneus, 96 Platygyne type, 57, 58 Omphalea, 62, 105 * Platygyne hexandra, 58

* diandra, 63 Pleiostemon type, 30 * Ophthalmoblapton macrophyllum, 99 Pleiostemon verrucosus, 30 Ostodes paniculata, 51 Plukenetia configuration, 60, 65, 105 pendulus, 51 Plukenetia type, 19, 62 Plukenetia verrucosa sybtype, 63

Pachystroma type, 99 Plukenetia volubilis subtype, 62 Pachystroma, 96 Plukenetia, 62 * longifolium, 100 abutifolia, 62 Pachystilidium type, 65 buchtienii, 63 Pachystylidium hirsutum, 65 conophorum, 63 Paivaeusa dactylophylla, 41 corniculatus, 63 Pantadenia, 48 tamnoides, 63

* adenanthera, 51 verrucosa, 63

* Paradrypetes, 5 volubilis, 62 POLLEN MORPHOLOGY OF THE EUPHORBIACEAE 115

Pogonophora schomburgkiana, 90 * virosa, 26 Polyandra, 82, 83 Seidelia type, 79, 88 Poranthera corymbosa, 29 Seidelia, 54, 60 microphylla, 29 triandra, 88

* Prosartema gaudichaudii, 60 Senefeldera macrophylla, 105 * Protomegabaria macrophylla, 22 Senefelderopsis, 6

* Pseudagrostistachys africana, 76 Speranskia type, 73, 75, 95

* Pseudanthus nematophorus, 43 Speranskia pekinensis, 76 * pimeleoides, 43 Sphaerostylis, 57 Pseudocroton 95 type, natalensis, 63 Pseudocroton tinctorius, 95 tulasneana, 57, 63 * Pseudolachnostylus glauca, 34 Sphyranthera, 6

* Pterococcus corniculatus, 63 Spirostachys venenifera, 97 Ptychopyxis costata, 81 Spondianthus preussii, 22 kingii, 81 Stachystemon type, 41

* Putranjiva type, 44 Stachystemon vermicularis, 43 * Putranjiva roxburghii, 44 Stenadenium type, 101 Pycnocoma subtype, 80 * Stenadenium spinescens, 101 * 80 97 Pycnocoma cornuta, Stillingia gymnogyna, macrophylla, 81 Strophioblachia fimbricalyx, 51 Sumbavia configuration, 69, 73, 105 6 Sumbavia Ramelia, type, 19, 69, 70, 72 Reverchonia, 21 Sumbavia, 105 * * arenaria, 24 rottleroides, 70

Richeria type, 26 Sumbaviopsis albicans, 70 Richeria laurifolia, 28 Suregada, 48, 53 Richeriella, 21 glomerulata, 53 Richeriella gracilis, 26 * subglomerulata, 53 Ricinocarpus, 48 Symphyllia siletiana, 94 pinifolius, 53 Synadenium arborescens, 101 Ricinodendron heudelotii, 51 Syndyophyllum, 6

Ricinus type, 19, 79, 86, 88 * Ricinus communis, 86 * Tannodia cordifolia, 53 Riseleya, 6 Tetracarpidium conophorum, 63 Romanoa, 10, 62, 63 Tetracoccus ilicifolius, 41 * Tetraplandra gibbosa, 99 Sagotia, 48, 105 Thecacoris leptobotrya, 22 51 Tetrorchidium 56 racemosa, 48, type, Sandwithia guyanensis, 53 Tetrorchidium, 48, 56 Sapium aubletianum, 99 * didymostemon, 57 ellipticum, 99 rubrivenium, 57 klotzschianum, 99 Thelypetalum, 6 longifolium, 97 Thymelaeaceae, 19 * montanum, 99 Thyrsanthera suborbicularis, 70 57 sebiferum, 99 Tragia fallax type, 19, Sauropus androgynis, 39 Tragia tristis subtype, 63 Savia type, 32, 34, 36 Tragia, 18, 58 Savia andringitrana, 34 capensis, 63 * erythroxyloides, 24, 33 fallax, 58 sessiliflora, 34 geraniifolia, 65

Sebastiania chamaelea, 97 ramosa, 65 corniculata, 97 sellowiana, 58 schottiana, 97 * stolziana, 63 * 63 Securinega type, 19, 20, 21, 25, 26, tristis, 32, 39 volubilis, 65 Securinega subtype, 25, 26 Tragiella, 57 Securinega, 25, 30, 32 * Trewia nudiflora, 80 congesta, 22 Trigonopleura, 73

* neopeltandra, 26 malayana, 90 ramiflora, 26 Trigonostemon redioides type, 58

suffruticosa, 25 Trigonostemon verrucosus type, 58 116 W. PUNT

Trigonostemon, 73 kirkiana, 36 fungii, 58 longifolius, 60 Vaupesia cataractarum, 53

* rediodes, 60 Veconcibea latifolia, 83

* verrucosus, 58

Tritaxis, 48 Wetria macrophylla, 80 gaudichaudii, 51 Wielandia elegans, 34

Uapaca, 32 Zimmermannia type, 20, 29 * * heudelotii, 36 Zimmermannia capillepes, 29