Full text of "Flora of Australia. Vol. 1 : Introduction"

See other formats

Volume I | :
Introduction

system of A.J. Cronquist (1981).

Volume 1

Introduction

Volume 2

Magnoliales
Winteraceae
Himantandraceae
Eupomatiaceae
Austrobaileyaceae
Magnoliaceae
Annonaceae
Myristicaceae

Laurales
Monimiaceae
Idiospermaceae
Lauraceae
Hernandiaceae

Piperales
Piperaceae

Aristolochiales
Aristolochiaceae

Nymphaeales
Nelumbonaceae
Nymphaeaceae
Cabombaceae
Ceratophyllaceae

Ranunculales
Ranunculaceae
Berberidaceac
Menispermaceae

Papaverales
Papaveraceae
Fumariaceae

Volume 3

Hamamelidales
Hamamelidaceae

Urticales
Ulmaceae

Cannabaceae
Moraceae
Urticaceae

Fagales
Balanopaceae
Betulaceae
Fagaccae

Casuarinales
Casuarinaceac

Volume 4

Caryophyllales
Phytolaccaceae
Nyctaginaceae
Aizoaceae
Cactaceae
Chenopodiaceae

Volume 5

Amaranthaceae
Portulacaceae
Basellaceae
Molluginaceae
Caryophyllaceae

Polygonales
Polygonaceae

Plumbaginales
Plumbaginaceae

Volume 6

Dilleniales
Dilleniaceae

Theales
Ochnaceae
Theaceae
Actinidiaceae
Elatinaceae
Clusiaceac

Volume 7

Malvales
Elacocarpaceae
Tiliaceae
Sterculiaceae
Bombacaceae
Malvaceae

Volume 8

Lecythidales
Lecythidaceae

Nepenthales
Nepenthaceae
Droseraceae

Violales
Flacourtiaceae
Bixaceae
Cistaceac
Violaceae
Tamaricaceae
Frankeniaceae
Passifloraceae
Cucurbitaceae
Datiscaceae

Salicales
Salicaceac

Capparales
Capparaceae
Brassicaceae
Moringaceae
Resedaceae

Batales
Gyrostemonaceae
Bataceae

Volume 9

Ericales
Epacridaceae
Ericaceae

Contents of yolumes in the Flora of Australia, the families arranged according to the

Volume 10

Ebenales
Sapotaceae
Ebenaceae
Symplocaceae

Primulales
Myrsinaceae
Primulaceae

Rosales
Connaraceae
Eucryphiaceae
Cunoniaceae
Davidsoniaceae
Pittosporaceae
Byblidaccac
Grossulariaceae
Crassulaceae
Cephalotaceae
Saxifragaceae
Rosaceae
Chrysobalanaceae
Surianaceae

Volumes 11,12

Fabales
Mimosaceae
Caesalpiniaceae

Volumes 13,14,15

Fabaceae

Volumes 16,17

Proteales
Elacagnaceae
Proteaceae

Volume 18

Podostemales
Podostemaceae

Haloragales
Haloragaceae
Gunneraceae

Myrtales
Sonneratiaceae
Lythraceae
Thymelaeaceae
Punicaceae
Onagraceae
Melastomataceae
Combretaceac
Trapaceae

Volume 19,20,21

Myrtaceae

Volume 22

Rhizophorales
Rhizophoraceae

Cornales
Alangiaceae

Santalales
Olacaceae
Opiliaceae
Santalaceae
Loranthaceae
Viscaceae
Balanophoraceae

Rafflesiales
Rafflesiaceae

Celastrales
Celastraceae
Hippocrateaceae
Stackhousiaceae
Aquifoliaceae
Icacinaceae
Cardiopteridaceae
Corynocarpaceae
Dichapetalaceae

Volume 23

Euphorbiales
Euphorbiaceae

——

Volume 24

Rhamnales
Rhamnaceae
Leeaceae
Vitaceae

Linales
Erythroxylaceae
Linaceae

Polygalales
Malpighiaceae
Tremandraceae
Polygalaceae
Xanthophyllaceae

Volume 25

Sapindales
Melianthaceae
Akaniaceae
Sapindaceae
Aceraceac
Burseraceae
Anacardiaceae
Simaroubaceae

——_——

Volume 26

Meliaceae
Rutaceae
Zygophyllaceae

Volume 27

Geraniales
Oxalidaceae
Geraniaceae
Tropacolaceae

Apiales
Araliaceae
Apiaceae

Volume 28

Gentianales
Loganiaceae
Gentianaccae
Apocynaceae
Asclepiadaceae

Volume 29

Solanales
Solanaceae

Volume 30

Convolvulaceae
Cuscutaceae
Menyanthaceae
Polemoniaceae
Hydrophyllaceae

Lamiales
Boraginaceae
Verbenaceae

Volume 31

Lamiaceae

Volume 32

Callitrichales
Callitrichaceae

Plantaginales
Plantaginaceae

Scrophulariales
Oleaceae
Scrophulariaceae

Volume 33

Myoporaceae
Orobanchaceae
Gesneriaceae
Acanthaceae
Pedaliaceae

Bignoniaceac
Lentibulariaceae

Volume 34

Campanulales
Sphenocleaceae
Campanulaceae
Stylidiaceae
Donatiaceae

Volume 35

Brunoniaceae
Goodeniaceac

Volume 36

Rubiales
Rubiaceae

Dipsacales
Caprifoliaceae
Valerianaceae
Dipsacaceae

Volume 37,38

Asterales
Asteraceae

Volume 39

Alismatales
Limnocharitaceae
Alismataceae

Hydrocharitales
Hydrocharitaceae

Najadales
Aponogetonaceae
Juncaginaceae
Potamogetonaceae
Ruppiaceae
Najadaceae
Zannichelliaceae
Posidoniaceae

a=
_ MUSEUM OF VICTORIA

IMM

Cymodoceaceae
Zosteraceae

Triuridales
Triuridaceae

Arecales
Arecaceae

Pandanales
Pandanaceae

Arales
Araceae
Lemnaceae

Volume 40

Commelinales
Xyridaceae
Commelinaceae

Eriocaulales
Eriocaulaceae

Restionales
Flagellariaceae
Restionaceae
Centrolepidaceae

Juncales
Juncaceae

Volume 41,42

Cyperales
Cyperaceae

Volume 43,44

Poaceae

Volume 45

Hydatellales
Hydatellaceae

Typhales
Sparganiaceae
Typhaceae

Bromeliales
Bromeliaceae

Zingiberales
Musaceae
Zingiberaceae
Costaceae
Cannaceae
Marantaceae

Liliales
Philydraceae
Pontederiaceae
Haemodoraceae
Liliaceae

Volume 46

Iridaceae
Agavaceae
Xanthorrhoeaceae
Hanguanaceae
Taccaceae
Stemonaceae
Smilacaceae
Dioscoreaceae

Volume 47

Orchidales
Burmanniaceae
Corsiaceae
Orchidaceae

Volume 48

Gymnospermae
“
Pteridophyta

Volume 49 et seq.

Non-vascular
plants

=
~
ye

FLORA OF AUSTRALIA

George Bentham (1800-1884), author of Flora Australiensis, the only previous
complete Australian Flora. Reproduced by courtesy of the Director, Royal Botanic
Gardens, Kew.

BUREAU OF FLORA AND FAUNA, CANBERRA

FLORA OF
AUSTRALIA

Volume |
Introduction

Australian Government Publishing Service Canberra 1981

EDITORIAL COMMITTEE

Sir Rutherford Robertson (Chairman)
Barbara G. Briggs
Hansjoerg Eichler

Leslie Pedley
James H. Ross
David F. Symon
Paul G. Wilson

Alison McCusker (Secretary)

Executive editor

Alexander S. George

Printed at Griffin Press Limited, Marion Road, Netley, South Australia.

CONTENTS

Contributors to Volume 1 vi
Floral emblems of Australia and its States viii-ix
Map of Australia x
Introduction 1
The background to the Flora of Australia A.S. George 3
The Australian flora: its origin and evolution B.A. Barlow 25
An introduction to the system of classification used in the

Flora of Australia A. Kanis 77
Key to families of flowering plants H.7. Clifford 113
Glossary A. McCusker 169
Index 199
End papers

Front: Contents of volumes in the Flora of Australia, the families
arranged according to the system of A.J. Cronquist (1981).

Back: Flora of Australia: Index to families of flowering plants.

CONTRIBUTORS TO VOLUME 1

Dr Bryan A. Barlow, Curator, Herbarium Australiense,
Commonwealth Scientific and Industrial Research Organisation,
P.O. Box 1600, Canberra City, Australian Capital Territory 2601.

Dr H. Trevor Clifford, Botany Department, University of
Queensland, St. Lucia, Queensland 4067.

Mr Alexander S. George, Bureau of Flora and Fauna, Department
of Home Affairs and Environment, P.O. Box 1252, Canberra City,
Australian Capital Territory 2601.

Dr Andrew Kanis, Herbarium Australiense, Commonwealth
Scientific and Industrial Research Organisation, P.O. Box 1600,
Canberra City, Australian Capital Territory 2601.

Dr Alison McCusker, Acting Director, Bureau of Flora and Fauna,
Department of Home Affairs and Environment, P.O. Box 1252,
Canberra City, Australian Capital Territory 2601.

FLORAL EMBLEMS OF AUSTRALIA
AND ITS STATES

Australia (unofficial) Western Australia
Acacia pycnantha Benth., Golden Wattle. Anigozanthos manglesii D. Don,

Photograph — J. G. & M. H. Simmons. Mangles’ Kangaroo Paw.
Photograph — A. S. George.

Northern Territory

Gossypium sturtianum J. H. Willis, South Australia

Sturt’s Desert Rose. Photograph — Clianthus formosus (Don) Ford & Vick.,
J. R. Maconochie. Sturt Pea. Photograph — A. S. George.

Queensland

Dendrobium bigibbum Lindley & Paxton,
Cooktown Orchid. Photograph —

M. W. Hodge.

Victoria
Epacris impressa Labill., Common Heath.
Photograph —B. Fuhrer.

New South Wales
Telopea speciosissima R. Br., Waratah.
Photograph — A. D. Chapman.

Tasmania
Eucalyptus globulus Labill., Blue Gum.
Photograph — I. G. Holliday.

oF | VEL

| o&Zl oFlL Alt \
$842WO}Iy O09 00b 002 Qo oo!
J1v9s
| VITIVULSNV oof
oFf iG
Nate | fy T etiam i
’ VIHOLOIA |
ae~| > =)
eth | Peceiiow »
i Fas “ SITY | a | 4H9lg Nylivy¥isny 1¥349 00€
of ‘ F j } ;
a WAinosaman 4 ~ e
OT OE Fe
eae EF S |
PHS eerie Dp eget gi» ‘i |
té se man . ‘ 0
Nes, poukqsng § 4 } iviiveisny | ig
? ; | | rol. Hines hes | mm.
- a as , Ps
y) | | Pe oe er XZ | viivuisny ae
o\gAT Gur betas joa 5 = Wa gts NEN ee A
ae A A / re = ‘ NYSLSaM
~~~. _ 7 eH onvisnasno / Fs
me. } }

_ Sbulids e211ylo

|
% = | AMOLINYSL
eg * 7 .
| Ne eee ion
t]

\ VWISVINIZdu YD
VIS IPy95

“ dO =47N9 ea
Seal eR UIMJego
San UJ i OY CS ye

peri. @@~_VISANOGNI
AST ye He, Pe.

INTRODUCTION

The Flora of Australia is intended for use by professional botanists and other
scientists, knowledgeable amateurs and students requiring botanical information. It
will include all flowering and non-flowering plants known to be indigenous or
naturalised in Australia but will exclude bacteria.

The geographical area covered by the Flora includes the six Australian States, the
Northern Territory, the Australian Capital Territory, immediate offshore islands and
Macquarie Island. Other Australian-administered territories, such as Lord Howe
Island and Christmas Island, are excluded. The occurrence in those territories of
species included in the Flora will be added to the notes on distribution. A complete
Flora of those territories is proposed as a separate volume.

Nomenclatural coverage will comprise accepted names together with synonyms
relevant to Australia, all with references to the original publication and type
collections. Where necessary, new taxa and new combinations will be published in an
appendix in the relevant volume. Significant references to families and genera will be
cited. Author abbreviations follow the Draft Index of Author Abbreviations compiled
at the Herbarium, Royal Botanic Gardens, Kew (HMSO, 1980). Journal titles are
abbreviated in accordance with G. H. M. Lawrence et al., Botanico-Periodicum-
Huntianum (Hunt Botanical Library, 1968), and other literature in accordance with
F. A. Stafleu and R. S. Cowan, Taxonomic Literature, edn 2 (W. Junk, 1976-),
except that upper case initial letters are used. The abbreviation ‘Austral.’, for
‘Australia’ and its derivatives, is used consistently except that this publication, Flora
of Australia, is cited as ‘Fl. Australia’ in order to avoid confusion with Flora
Australiensis (‘Fl. Austral.’).

Descriptions will be concise. They will be based on Australian material except
where a broader view is necessary (especially in descriptions of families or genera) to
avoid giving misleading taxonomic information. Distributional data will be given in
both descriptive and mapped forms. A selection of up to five representative
collections will be cited for each species. All herbarium sheets examined for the Flora
of Australia will be so labelled. Verified ecological information and chromosome
numbers will be included, and phytochemical information added if of special interest.

The system of A. J. Cronquist has been adopted for the arrangement of families.
The sequence for those families occurring in Australia is included on the front
endpapers of this volume and will be reproduced in all subsequent volumes. The
families are listed alphabetically on the back endpapers as an index to volumes.
Volumes will be issued out of numerical sequence, the order to be determined largely
by the availability of specialist contributors or of recent revisions on which flora
treatments can be based. Within families, genera and species will be arranged so as to
show natural relationships as far as possible. Because the Flora will be based largely
on existing knowledge, the standard of treatment will vary from group to group. For
the same reason it will sometimes be necessary to make arbitrary decisions on points
of taxonomy and nomenclature, for example, in this volume, the spelling of
Brachycome.

A glossary defining botanical terms is included in this volume. Specialised terms
used in certain groups of plants will be explained in supplementary glossaries in the

relevant volumes.

Introduction

Acknowledgments

Many people have co-operated to bring the Flora of Australia project to fruition.
Botanists throughout Australia and in other countries have contributed, either
individually or through their institutions, to planning the Flora and to the evolution
of the format. Many have commented constructively on the chapters in Volume 1,
especially the Key to Families and the Glossary.

Arthur. J. Cronquist, New York Botanical Garden, made available a draft of the
latest version of his system of classification for use in planning the arrangement of
families. He responded promptly to requests for advice in allocating genera to
families. Robert. F. Thorne, Rancho Santa Ana Botanic Garden, and Rolf. M. T.
Dahlgren, Botanic Museum of the University of Copenhagen, provided the latest
information on their phylogenetic systems of classification for use in the chapter by
Kanis. The Director, Royal Botanic Gardens, Kew, made available copies of portraits
of Bentham, Lindley, Hooker and Mueller for the frontispiece and Figures 4-6. The
portrait of Brown (Figure 2) is reproduced by courtesy of the Linnean Society of
New South Wales. Colin Totterdell, Division of Plant Industry, CSIRO, provided
photographs for Figures 1, 3, 7, 8, and 14-17. Elizabeth Kemp, Bureau of Mineral
Resources, provided copies for Figures 9-13. Sue Craven prepared the map of
Australia facing page 1. Helen Hewson prepared Figures 23-26.

The Key to Families of Flowering Plants in Australia is modified from Keys to
the Families and Genera of Queensland Flowering Plants (Magnoliophyta) by H. T.
Clifford and Gwen Ludlow, edn 2 (University of Queensland Press, 1978). Those
keys were based on an unpublished key prepared by the late A. Cayzer. They have
been used widely in Queensland but less so elsewhere in Australia. Comments on the
key will be welcomed by the Executive Editor.

Special effort was needed to produce Volume 1 in time for the XIII International
Botanical Congress in Sydney, August 1981. The assistance of the Commonwealth
Government, especially the Department of Home Affairs and Environment and the
former Department of Science and the Environment, is acknowledged for
co-operation in achieving this goal. David Ride, the first Director of the Bureau of
Flora and Fauna, and later Alison McCusker as Acting Director, have carried most
of the administrative responsibilities in establishing the Flora program. Alison
McCusker also assisted in editing Volume 1. The staff of the Bureau has
enthusiastically undertaken its part in preparing the volume. Arthur Chapman assisted
greatly in editing and proof-reading. John Busby developed typesetting procedures
and typeset this volume, using facilities of the Bureau of Flora and Fauna and the
Division of Computing Research, CSIRO. Wendy Riley and Geetha Sriprakash typed
the manuscript. David Marshall and Jennifer Longstaff, Australian Government

Publishing Service, assisted and advised with designing the book. Jennifer Longstaff
designed the cover.

Sir Rutherford Robertson has given the Flora project support over many years.
As a Fellow and former President of the Australian Academy of Science, he played a
leading role in the initiatives that resulted in the establishment of the Bureau of Flora
and Fauna to co-ordinate the Australian Biological Resources Study, of which the
Flora of Australia project forms a major part. Further, as the first Chairman of the
Editorial Committee, he has firmly guided the project during its first year.

THE BACKGROUND TO THE
FLORA OF AUSTRALIA

A. S. George

History of the Flora of Australia Project

The project to write a Flora of Australia is the first of its kind in this country. Only
one previous Australian Flora has been completed, Flora Australiensis (1863-1878),
written by George Bentham who never visited Australia. The new Flora is the most
exciting botanical project undertaken in Australia. It has had a long gestation and a
difficult birth; its completion, like that of works such as de Candolle’s great
Prodromus (1823-1878) and Martius’ Flora Brasiliensis (1840-1906), will be a major
achievement of national and international co-operation.

Like all Floras, Bentham’s Flora Australiensis was out of date as soon as the last
volume was published. The seven volumes spanned 16 years, from 1863 to 1878, and
were written entirely by George Bentham using the collections at Kew, the British
Museum (Natural History) and Paris, as well as those sent on loan from Melbourne.
During this period botanical work was expanding in Australia. Field collectors were
active, many of whom were encouraged by Ferdinand Mueller, Government Botanist
of Victoria. Mueller himself was in the heyday of a long and productive career.
Botanists, both professional and amateur, were beginning to study the flora in other
States. Bentham had planned a supplement but, in the preface to Volume 7 of Flora
Australiensis, he wrote that it ‘would entail more labour than at my age it would be
prudent to undertake’; he was then 78. Instead, he encouraged Mueller to produce a
complete census of the flora. Mueller accomplished this by 1882 and revised it in
1889.

State Floras, mostly based on Flora Australiensis with the addition of species
discovered later, were issued over the succeeding years in all States except Western
Australia, where a systematic census, prepared by the Government Botanist Charles
Gardner, appeared in 1930-31. Most of these Floras were compiled by professional
taxonomists appointed by State Governments or by universities. Because the botanists
were few in number, demands on their time were such that they were often able to
do little research. This problem, common to most botanists in Australia, is slowly
being alleviated as more positions are created so that more people are available to
share or assume routine responsibilities. By the 1900s, however, the first of many
accomplished amateur taxonomists to contribute to the literature on the Australian
flora had appeared on the scene. J. M. Black, a retired journalist, published The
Naturalised Flora of South Australia in 1909, followed by his Flora of South
Australia in 1922-29. The latter is currently in its third edition, revised by John
Jessop, Chief Botanist of the State Herbarium of South Australia.

The first reference to a new national Flora appears to be that by Joseph Maiden,
Government Botanist and Director of the Botanic Gardens, Sydney, in 1907. In his
Presidential Address to Section D (Biology) at the eleventh meeting of the Austral-
asian Association for the Advancement of Science, he suggested that each State issue
supplements to Flora Australiensis, and went on to say:

The form of the new ‘Flora Australiensis’ (which cannot be published until Western
Australia is more thoroughly explored botanically) will then fitly take the form of the
most modern classification available, which, at the present moment, is of course that of

FLORA AUSTRALIENSIS:

A DESCRIPTION

OF THE

PLANTS OF THE AUSTRALIAN TERRITORY.

BY
GEORGE BENTHAM, F.R.S., P.L.S.,
ASSISTED BY

FERDINAND MUELLER, M.D., F.B.S. & L.S.,

GOVERNMENT BOTANIST, MELBOURNE VICTORIA,

VOL. I.
| RANUNCULACEZ TO ANACARDIACER.

PUBLISHED UNDER THE AUTHORITY OF THE SEVERAL GOVERNMENTS
OF THE AUSTRALIAN COLONIES, :

LONDON:
LOVELL REEVE any CO., 5, HENRIETTA STREET, COVENT GARDEN.

1863.

Figure 1. Titlepage of Volume 1 of George Bentham’s Flora Australiensis (1863).

Background

Engler, although even that fine arrangement need not be slavishly followed in every
detail.

We in Australia suffer much through our geographical isolation from the great intel-
lectual centres of the Northern Hemisphere. That is our misfortune, but we should not
fail in our endeavors to advance knowledge of the botany of this continent, and potent
help in this direction would be the issue of an ‘Australian Flora’ based on the most
modern lines of taxonomic research, modified, indeed, by our own special knowledge of
our own plants and their affinities.

Nine years later, however, Maiden acknowledged that a new Flora was some time
off. In the preface to the Census of New South Wales Plants (1916), compiled jointly
with Ernst Betche, he wrote that Bentham’s Flora Australiensis ‘is, and will long
remain, the standard work on our flora. The greater one’s experience with it, the

more sincere is one’s admiration of it’. This opinion has been echoed by most Aust—
ralian taxonomists.

While the need for a new Flora was realised and occasionally mentioned, there

seems to have been no attempt to fulfil that need during the first half of the 20th
Century.

The period after the Second World War was a quiet one for the Flora proposal.
The staff of botanical institutions were still preoccupied with routine work, pre-
paration of State floras, and individual lines of research. With every year, however,
the need became more urgent, yet still no firm action was taken.

At the 25th meeting of the Australian and New Zealand Association for the
Advancement of Science (ANZAAS) in Adelaide, August 1946, a meeting of plant
taxonomists recommended the formation of a Systematic Botany Committee. The
meeting listed, under ‘immediately desirable tasks’, the ‘preparation of floras,
especially for some States’. Clearly there was no strong feeling about a national Flora.
The Committee fostered communication among the taxonomic community by issuing
a newsletter entitled the Australasian Herbarium News. In the first issue, of June
1947, William Hartley, then Senior Plant Introduction Officer with CSIRO, called for
the establishment of a new Commonwealth Herbarium which could facilitate the pre—
paration of a Flora (Hartley, 1947). He envisaged that the Flora would be prepared
by many botanists from the States, with the Commonwealth Government funding
replacement staff during their period of commitment.

William Hartley’s appeal brought no positive response. The next meeting of
ANZAAS, in Perth, August 1947, again urged progress with State floras. This atti—
tude, as stated by Stanley Blake, a senior botanist with the Queensland Herbarium,
persisted through subsequent meetings including the 31st at Melbourne in 1955, at
which ‘an attempt to do something more definite . . . met with little response’
(Blake, 1960). The Australasian Herbarium News, during the eight years that it, was
published, carried no further reference to a Flora.

The initial impetus to the campaign which finally led to the current Flora of
Australia came from a newcomer to the Australian botanical scene, Hansjoerg
Eichler. In 1957, less than two years after arriving from Germany to take up the
position of Keeper in the State Herbarium of South Australia, Eichler recommended
that his staff be permitted to undertake Australia-wide revisions which could be used
towards a new Flora of Australia. This was a major change in policy; previously all
States had largely confined research within their borders. Joseph G. Wood, then Pro-
fessor of Botany at the University of Adelaide and Chairman of the Handbooks
Committee of the Flora and Fauna of South Australia, immediately took up the sug—
gestion for a national Flora and had it placed on the agenda for the 33rd ANZAAS
Congress, held in Adelaide in August 1958. This time the topic aroused extensive
discussion, during which it became clear that opinion was divided on the level of

Background

detail that would be appropriate for a Flora. There was support on the one hand for a
monographic approach, based on full revision of all groups, and on the other for a
concise treatment based solely on existing published knowledge. Eichler proposed the
creation of a central taxonomic unit with 10 botanists producing revisional studies for
a Flora.

ANZAAS resolved to set up a Flora of Australia Committee ‘to prepare estimates
and detailed plans of the organization required for the preparation of a new Flora
Australiensis’. Members of the Committee were R. T. M. Pescott (Convener), S. T.
Blake, D. J. Carr, Hj. Eichler, L. A. S. Johnson, S. Smith-White and D. E. Symon.
A meeting was held in Melbourne on 22-25 April 1959, at which Blake was elected
Chairman. Following intensive debate, a report was prepared recommending that a
monographic work be produced, to be called Flora of Australia. The Committee dis—
missed the concept of a Flora based only on existing published knowledge, as not
serving ‘any useful purpose’ (Blake, 1960). The idea of a generic Flora was also
rejected, first because it would hinder the preparation of a full Flora, and second,
because the species should be better known before genera could be properly
delimited. The report envisaged that the Flora would be produced over a period of
about twenty years by a central organisation with a staff of fourteen taxonomists
under the direction of an Editor-in-Chief. It suggested that the organisation might be
at Canberra but that some of the taxonomists could be stationed at existing herbaria
or universities.

The Committee estimated that the Australian flora contained over 15 000 species
and that a monographic treatment would amount to 30 000 pages. The cost at 1959
rates was estimated at £70 000 ($140 000) per annum for salaries, £15 000 ($30 000)
for equipment, an unspecified amount for ‘normal running costs’, and ‘ample funds
for field work and for travel within Australia and abroad’. The Committee, noting
that at that time there were less than 20 workers in taxonomy in State and Common-—
wealth herbaria and about six in universities, of whom none could devote full time to
their researches, stated that graduates would have to be trained, although the ‘initial
staff would consist largely of experienced taxonomists’.

The Committee’s report was adopted by ANZAAS at the 34th Congress in Perth,
August 1959. A delegation from ANZAAS in July 1960 presented the report to the
Prime Minister’s Department, which in turn referred it to the Australian Academy of
Science. The Academy, recognising the need not only for a Flora but also for a simi-
lar study of the Australian fauna, recommended to the Prime Minister of the day, the
Right Honourable R. G. Menzies, that a Museum of Australian Biology be estab-
lished with the principal aims of conducting a biological survey of Australia and
writing a ‘comprehensive multi-volume Flora of Australia’. The Government at that
time was unable to finance the museum, although it did not refute the need for such
a development. Throughout the period leading to the final decision to proceed with a
new Flora, the Academy continued to give strong support to the concept.

A facsimile edition of Bentham’s Flora Australiensis, published by Asher and
Reeve in 1967, drew international attention to the lack of a modern Flora (Stafleu,
1967). It also prompted John Beard, then Director of Kings Park and Botanic
Garden, Perth, to suggest that a concise Flora be compiled along the lines of Flora
Europaea (Beard, 1968). Beard considered that such a Flora could be written by a
small group of botanists working in Canberra.

The 1960s saw great economic development in Australia, especially in agriculture,
mining and industry. At the same time awareness of its effects on the environment
became more widespread, leading to a great surge in concern for the natural environ-
ment. In the public and private sectors, the need for environmental surveys in both

Background

settled and remote areas placed great demand on the services of botanists and made
even more apparent the lack of a national Flora. During the same period horticultural
interest in the indigenous flora also increased markedly.

In April 1967 the Honorary General Secretary of ANZAAS wrote to the Prime
Minister expressing regret at the lack of support for a new Flora and emphasising the
importance of the project. The proposal was again referred to the Academy of
Science which appointed a Flora and Fauna Committee to examine it.

While ANZAAS continued to promote the ‘Flora of Australia’ concept, the Zoo-—
logical Subcommittee of the Academy’s Flora and Fauna Committee in 1968 can—
vassed the various State museums and found general support for a Commonwealth
biological survey. By that time, State herbaria also were willing to collaborate in pro—
ducing a national Flora. The Flora and Fauna Committee released a report in Octo-
ber 1968 in which it proposed that an organisation, to be called a Biological Survey
of Australia, be established (Anon., 1968). The report proposed that the Survey
would initiate the production of a new Flora of Australia; it was still envisaged that
the Flora would be monographic. The suggestion was made that existing herbaria in
Canberra might form the basis of the botanical collections. At that time there were
separate, small herbaria, in CSIRO, the Forest Research Institute, the Botanic Gar-—
dens and the Australian National University. The Committee considered that collab—
oration with herbaria in the States would be essential. Early in 1969 Sir Macfarlane
Burnet, then President of the Academy, led a delegation to the then Minister for
Education and Science, the Honourable J. M. Fraser, to press the claim for establish—
ment of a Biological Survey of Australia.

In 1970 and 1971 events occurred that greatly stimulated discussion on a new
Flora and led to the commencement of preliminary work for it. For the James Cook
Bicentenary in 1970 William Stearn, a distinguished botanist with the British Museum
(Natural History), was invited to address the Australian Academy of Science. During
his address, Stearn referred to the conspicuous absence of a modern Australian Flora
and to the urgent need to write one. He was later approached confidentially by Sir
Maurice Mawby, a Fellow of the Academy, who discussed with him the possibility of
raising private funds to help launch work on a new Flora. Stearn referred Sir Maurice
to John Beard, then Director of the Royal Botanic Gardens, Sydney. Beard drew up
a proposal for regional Floras to cover Australia in four phytogeographic regions—
South-eastern, Tropical, Eremean and South-western; these Floras would be written in
five years, possibly by staff in the various herbaria. Sir Maurice’s offer to assist was
conditional upon support for the project being received from both the Academy and
the Australian botanical community.

In February 1971 a meeting was held in Canberra to ‘discuss an Information Ret-—
rieval Base for the information on herbarium labels. The agenda included an item on
possible actions to promote preparation of a new Flora of Australia. Beard presented
to the meeting his proposal for regional floras and indicated that private funds might
become available to begin the work. The presentation surprised most delegates since
they had been unaware of these developments, but the meeting tentatively supported
the proposal. Within weeks, however, alternative proposals were drawn up by groups
of botanists in Adelaide, Canberra and Melbourne. The Adelaide group, headed by
Eichler, circulated a questionnaire among Australian botanists to gauge opinion on
several possible courses of action. From this there emerged general support for a pre—
liminary work, an index of Australian plant names, which could be commenced with
the funds likely to be made available as a result of Sir Maurice’s initiative.

The 43rd ANZAAS Congress in Brisbane followed in May 1971, and the whole
Flora subject was discussed. Three proposals were submitted to the Academy of

Background

Science, for an Australian Plant Name Index, a Generic Flora of Australia, and a
series of Handbooks for regions not covered by floristic works. The first would pro—
vide basic data for a new Flora, the second would be a valuable source of information
on the flora as an expansion of the Dictionary of Australian Plant Genera (Burbidge,
1963), while the third would fill the gaps in the field of Australian regional floras.

The Academy in November 1971 set up a Standing Committee for a Flora of
Australia under the chairmanship of David G. Catcheside, then Director, Research
School of Biological Sciences, Australian National University. It consisted of an
experienced, active taxonomist from each State and the Australian Capital Territory
and six botanists from Australian universities. With general support from botanists for
the Australian Plant Name Index, the Standing Committee decided to initiate the
project, using the funds made available to the Academy through Sir Maurice Mawby.
Nancy Burbidge was released from her duties as Curator of the CSIRO herbarium to
lead the project, and Eichler took up the Curatorship. The Committee also discussed
the format for a Flora and arranged the preparation of sample treatments. Thus
important groundwork for a Flora was at last under way. Both the Academy and
CSIRO had been instrumental in reaching this goal. The Academy continued to
administer the project financially until 1976. CSIRO made available research and lib—
rary facilities.

In May 1972 the Academy wrote to the then Minister for Education and Science,
the Honourable J. M. Fraser, requesting reconsideration of the proposal to establish a
Biological Survey. Further support for this proposal came in the same year from a
House of Representatives Select Committee on Wildlife Conservation (Waterhouse,
1978).

During the 1970s active support for the project also came from an active amateur
group, the Society for Growing Australian Plants. The Society, its members acutely
aware of the need for accurate names and data on native plants used in horticulture,
on several occasions urged the Government to begin writing the Flora.

The need for a biological survey had now become sufficiently important for the
major Australian political parties to include it in their platforms for the Federal Elec—
tion in 1972 (Ride, 1978). It seemed only a matter of time before the survey would
be set up.

Communication and co-operation between Australian botanists received a boost
with the formation in April 1973 of the Australian Systematic Botany Society. First
proposed by a group of Victorian botanists, the Society rapidly gained a membership
of over 200 and now (1981) has over 300 members. Local chapters were formed in
the larger cities. The Society immediately began to play its part by preparing an
index to current plant taxonomic research in Australia. In 1976 John Jessop, who had
succeeded Eichler as head of the State Herbarium of South Australia, proposed that
the Society co-ordinate and edit a Flora of Central Australia. Although there was
concern that it might lessen support for a national Flora, the project went ahead, as it
was felt that it could be completed before work on a national Flora commenced.
Further, it was to be based primarily on published knowledge or that readily available
from specialists. The Flora of Central Australia (Jessop, 1981), prepared by over 50
contributors in three years, covers a major geographical region of the continent but,
with about 2 000 species, includes only ten per cent of the Australian flora. The pro-
ject has played its part both in directing attention to the need for Floras and in giving
many people experience in flora-writing.

A visit to Australia in 1973 by C. G. G. J. van Steenis, then Director of the
Rijksherbarium, Leiden, focussed attention on the scope and organisation of flora-

Background

writing through discussion of Flora Malesiana. Van Steenis strongly preferred a con-
cise flora, but some of the senior local voices still wanted a monographic work.

The Australian Plant Name Index project commenced in April 1973 with the ap—
pointment as bibliographer of Penelope Hack, who was succeeded in January 1974 by
Arthur Chapman. Nancy Burbidge directed this work and at the same time brought
up to date her earlier list of taxonomic literature available in Australian libraries
(Burbidge, 1951, 1978). She also planned three sample treatments for a Flora text, to
be made available for discussion. These were undertaken by herself (Loranthaceae),
Helen Hewson (Brassicaceae), and Ruurd Hoogland (Rhizophoraceae).

In 1973 the Government established the Interim Council of the Australian Bio—
logical Resources Study (ABRS). The Council’s functions were:

(a) Initially to promote through grants to existing State and Commonwealth institutions:
— the collection and scientific description (taxonomy) of species of animals and
plants throughout Australia;
— in-depth studies of the ecology of such species; and
— proper maintenance of collections.
(b) After a few years of operations, to consider and make recommendations in relation
to:
— conduct in the longer term of taxonomic and ecological studies; and
— housing, maintenance and display of national scientific collections (Waterhouse,
1978).
The Council was allocated $750 000 for the first three years. On the botanical side
grants were made for taxonomic and ecological studies and for the curation of
collections.

A picture of the state of taxonomic knowledge of the Australian flora was built
up, following an assessment by Nancy Burbidge in the early 1970s. Burbidge esti—
mated that 25 families of seed plants were sufficiently well known to be written up
for a Flora; 73 small families could also be written up without detailed research; 84
families required revision in most genera; 7 could be written up at a non-critical level;
and 33 were of doubtful position (Burbidge, 1974). In 1978 a survey conducted by
ABRS revealed that only 37 of the 222 flowering plant families recognised by Bur-
bidge were being actively studied in Australian herbaria (Ride & McCusker, 1978).
Although there was doubt as to the final format of the Flora, it was felt that a work
based on current knowledge would quickly lose value and that a ‘vigorous modern
Bentham’ was needed urgently to get on with the job (Ride, 1978).

The Interim Council of ABRS presented its report in 1975. The report was refer—
ted by the Government to an Administrative Review Committee and a Committee on
Co-ordination of Support for the Collection of Data in the Flora and Fauna of
Australia. The question of the location of ABRS within the Commonwealth Public
Service was considered by the Science Task Force of the Royal Commission on
Australian Government Administration. Recommendations from these committees
were finally referred to the Interim Australian Science and Technology Council
(ASTEC). Following the initial three-year operation of ABRS, its funding was con—
tinued in 1976-77, during which period the report of the Interim Council was passing
through the above committees. In 1976 financial support for the Flora project, which
up till then had been organised by Sir Maurice Mawby and the Australian Academy
of Science, was exhausted. Following an approach by the Academy, the project was
taken over by ABRS.

A note of frustration appeared in the report of the Systematic Botany Committee
of ANZAAS in 1976: ‘The time lost on the Flora project since concrete proposals for
it were submitted in 1959 is of scientific concern: progress in all fields of botany

Background

dealing with Australian plants . .. is severely hampered by the inadequacy of
taxonomic knowledge . . . and the lack of a comprehensive work in which modern
knowledge is made readily available’.

Further groundwork for a Flora was undertaken in 1976 by Paul Wilson, Senior
Botanist with the Western Australian Herbarium, while on secondment to ABRS. He
prepared a set of Guidelines for Contributors to a Flora which were widely circulated
for comment among Australian taxonomists. Although prepared for a Flora which
would be published in family parts, the Guidelines nonetheless contributed signifi—-
cantly to the format eventually adopted.

In its report for 1976-77, the Interim ASTEC recommended the establishment of
a new body, the Institute of Australian Flora and Fauna (IAFF), to ‘support and co-
ordinate publication of a systematic series of regional floral handbooks’. It recom-—
mended that existing ABRS staff be incorporated into the new Institute. ASTEC saw
the initial role of the IAFF, in relation to flora, as one of ensuring consistency in
regional Floras, preparing and co-ordinating index volumes, and supporting taxonomic
studies and handbooks. This would pave the way for the writing of a more complete
Flora when appropriate funds became available. A further entreaty to the Govern—
ment to continue funding ABRS and to commence a Flora came in December 1977
from the Committee of Heads of the Australian Herbaria.

The question of a biological survey of Australia, including the preparation of a
national Flora, had now been under scrutiny for two decades. As a result of its inves—
tigations the Government, in 1978, formally established the Australian Biological
Resources Study within the Department of Science. The preparation and publication
of co-ordinating works on the flora were stated objectives. The introduction of a pro—
gram to write a new Flora of Australia now seemed assured, but its timing, scope and
format were still to be decided. The ABRS Advisory Committee was appointed by
the Minister for Science and held its first meeting on 6-8 March 1979. It decided to
recommend that a start be made immediately on a concise Flora of Australia. The
Committee felt that the time needed to prepare a monographic Flora was unaccept—
able; the work must be completed within 30 years, and planned so that groups in
urgent need of revision could be studied before the relevant volumes were issued. The
Committee’s recommendation was accepted by the then Minister for Science, Senator
the Honourable J. J. Webster, who announced the project on 24 April 1979.
Meanwhile, the scope and format were discussed at length among the taxonomic
community. Support for a monographic treatment waned as the enormous time-scale
involved became more apparent. An alternative proposal envisaged the publication of
reprints of revisions in a standard format so that they could be bound in volumes;
such a scheme might have been considered more thoroughly had not the Advisory
Committee decided to commence the concise Flora.

At its second meeting on 4-5 October 1979, the Advisory Committee decided
that the Flora would be based largely on current knowledge and ‘would be produced
in such a way as to be readily updateable’. It decided that, if possible, some parts
should be published in time for the XIII International Botanical Congress in Sydney,
August 1981.

In October 1979 a Flora Study Group was appointed, later to become the Editor—
ial Committee for the Flora of Australia, under the Chairmanship of Sir Rutherford
Robertson, Chairman of the ABRS Advisory Committee and Vice-chairman of
ASTEC. The Study Group wasted no time in determining the scope, arrangement
and format of the Flora. The initial choice lay between issuing volumes or family
parts. The Committee quickly decided in favour of volumes. Several systems of class—
ification were considered, the use of a phylogenetic system being preferred to any

Background

other arrangement because it would provide a definite framework and prevent groups
from being neglected. The system of Arthur J. Cronquist (Cronquist, 1981), then at a
late stage of revision, was chosen for the Flora.

The final administrative step of consolidation came in November 1979, when the
Bureau of Flora and Fauna was established as a Branch in the Environment Division
of the Department of Science and the Environment. A year later, the Division was
transferred to the new Department of Home Affairs and Environment.

Current state of knowledge of the Australian flora

The Australian flora is still far from being adequately known. Flora Australiensis
contained 8 125 species of vascular plants. In 1981 the number in the vascular flora
is unknown but estimated to be about 18 000 species; in addition there are several
thousand non-vascular species. A further significant increase will result from taxon—
omic revisions and more thorough botanical exploration. A sample of genera and sec—
tions of genera that have been revised in Australia during the past 40 years shows
that the average increase in species when such revisions are made is just under 50
per cent. The sample may not be representative in that workers may have selected
genera known to contain large numbers of undescribed species, though it included
revisions of genera in which few new species came to light, e.g. Phebalium (4 new
species in a total of 45) and Terminalia (2 in 29).

Few parts of Australia have been fully explored botanically. New species and
records continue to be turned up, even close to civilisation, and there are very large
areas—thousands of square kilometres—where no work at all has been done. This
applies especially to parts of the north and to Western Australia. Collecting in such
regions will in general extend the range of known species, but new discoveries are
certain to be made. Alien taxa continue to become naturalised at a steady rate. In an
analysis of the Victorian flora, for example, Ross (1976) calculated that the rate of
introduction of non-Australian species to that State had averaged five to six species
per year over the previous 100 years. There is little doubt that the Australian flora
will eventually be found to contain over 25 000 species.

Previous floristic works on Australia

The first Australian plants named under the binomial system were two species pub-
lished in 1768 by N. L. Burman. It was the large collection made by Joseph Banks
and Daniel Solander in 1770, however, which gave the first real insight into the
Australian flora. Unfortunately the magnum opus planned by Banks and Solander
was never published, and their collections were only partly studied by other botanists.
Banks encouraged and sometimes sponsored collectors to visit the continent, the most
important of these being Robert Brown. Brown’s participation in the coastal survey
by Matthew Flinders in 1801-1803, and his subsequent stay in New South Wales and
Tasmania, resulted in a collection of several thousand species. Brown commenced a
Flora of Australia but the first volume, published in 1810 (Prodromus Florae Novae
Hollandiae et Insulae Van-Diemen), was so disappointingly received that he never
completed the remainder. The Prodromus, arranged in a natural system, later came
to be recognised as a milestone in taxonomic botany.

Early works on the Australian flora were written and published in Europe, and
many were largely accounts of individual collections, e.g. Labillardiére (1804-1806)
and J. D. Hooker (1855-1860) based chiefly on their own collections, and Lehmann
(1844-1848) based on the collections of Ludwig Preiss and to some extent James
Drummond (see Annotated Bibliography). The Royal Gardens (later Royal Botanic

Figure 2. Robert Brown (1773-1858), author of Prodromus Florae Novae Hollandiae
et Insulae Van-Diemen (1810) and other works on the Australian flora. Painting by
H. W. Pickersgill, engraved by C. Fox; reproduced by courtesy of the Linnean

Society of New South Wales.

PRODROMUS

FLORZ NOV HOLLANDIE

INSULAE VAN -DIEMEN,

EXHIBENS

CHARACTERES PLANTARUM

QUAS

_ ANNIS 1802—1805
PER ORAS UTRIUSQUE INSUL# COLLEGIT ET DESCRIPSIT

ROBERTUS BROWN;

INSERTIS PASSIM ALIIS SPECIEBUS AUCTORI HUCUSQUE
GOGNITIS, SEU EVULGATIS, SEU INEDITIS. PRESERTIM

BANKSIANIS,

IN PRIMO ITINERE NAVARCHI COOK DETECTIS.

VOL. I.

LONDINI:

TYPIS RICHARDI TAYLOR ZT SOCII.

VENEUNT APUD J. JOHNSON ET SOCIOS, IN C@METERIG
SANCTI PAULI,

eee es

184,

Figure 3. Titlepage of Robert Brown’s Prodromus Florae Novae Hollandiae et Insulae
Van-Diemen (1810).

Background

Gardens) at Kew were associated with many early botanical collectors. By the 1850s
Kew, under the direction of William Hooker, was becoming a major centre of botani—
cal research. A series of colonial Floras was commenced there, Flora Australiensis
(1863-1878) by George Bentham being an important contribution to this program.
Ferdinand Mueller, the first resident plant taxonomist in Australia, had been keen to
write an Australian Flora but was dissuaded by Bentham and Joseph Hooker. They
considered that Mueller would be unable to do the work satisfactorily since he could
not examine the historical collections housed in European herbaria. Mueller co-
operated fully in the preparation of Flora Australiensis by making available to
Bentham the entire collection of the herbarium in Melbourne (Daley, 1928).

As Government Botanist of Victoria from 1853 to 1896, Mueller developed the
herbarium in that State into an institution of international importance. He encouraged
collectors to travel to many parts of the continent; while he himself collected widely
and produced a steady stream of taxonomic publications (for a bibliography of
Mueller’s works see Churchill, Muir & Sinkora, 1978). Mueller’s botanical output has
never been approached by later botanists in Australia. From his time onwards, how-
ever, the writing of floristic works on Australia has been carried out chiefly in this
country, but with much reliance on the historical material in Europe.

Flora Australiensis spawned a number of regional floras, many of which were for
the most part extracted from the major work. With time and the great increase in
new discoveries, the original work necessary to compile Floras increased, as shown in
works such as Black (1922-1929) and Ewart (1930). Floras were produced for all
States except Western Australia; that State still has no Flora, though it has produced
three censuses (Gardner, 1930-31; Beard, 1965; Green, 1981). Only South Australia,
Tasmania, Victoria and the Australian Capital Territory have Floras that are either
recent or kept up to date with new editions. There are modern local Floras for the
Sydney Region, North-eastern New South Wales, Western New South Wales and
Central Australia, and a Flora of South East Queensland is currently in preparation.

Annotated Bibliography

The following bibliography lists in chronological order the most significant floristic
works that have been written for Australia and major regions within it. Several early
taxonomic works of interest are also included. Publication years differing from those
on title-pages are given in square brackets.

Burman, Nicolaas Laurens (1768), Flora Indica. Haak, Leiden & Schreuder,
Amsterdam.

Contains the first two Australian plants named under the Linnaean system—both
described as ferns attributed to Java, but in fact species of Acacia (Mimosaceae)
and Synaphea (Proteaceae) from south western Australia.

Linnaeus, Carl (filius) (1781), Supplementum Plantarum Systematis Vegetabilium,
Generum Plantarum, et Specierum Plantarum. Braunschweig.
Contains descriptions of several Australian plants seen by Linnaeus in Banks’
herbarium.

Smith, James Edward (1793)[-1795], A Specimen of the Botany of New Holland.
Davis, London.
Descriptions of plants collected at Sydney by early settlers, chiefly John White.

Figure 4. John Lindley (1799-1865), author of the names of many Australian plants.

Portrait by J. H. Maguire, 1849; reproduced by courtesy of the Director, Royal
Botanic Gardens, Kew.

Background

Cavanilles, Antonio José (1800), Observaciones sobre el suelo, naturales y plantas del
puerto Jackson y Bahia-Botanica, Anales de Historia Natural 1, 3: 181-245.
Descriptions of the plants collected at Sydney in March-April 1793 by Luis Née,
a member of a Spanish expedition to the South Seas.

Labillardiére, Jacques Julien Houtou de (1804~-1806)[-1807], Novae Hollandiae
Plantarum Specimen, 2 vols. Huzard, Paris.
Descriptions of plants collected by Labillardiére and others in south-western
Australia and Tasmania in 1792, arranged in the Linnaean sexual system.

Brown, Robert (1810), Prodromus Florae Novae Hollandiae et Insulae Van-Diemen.
Taylor, London.

The first Flora of Australia, albeit incomplete, based largely on the extensive col-
lections made by Brown himself during the Flinders Voyage (1801-1803) and
afterwards in New South Wales and Tasmania. Only one of two projected vol-
umes published. One of the first major works to be based on a natural system.

Candolle, Augustin Pyramus de (et al.) [1824-](1823-1873), Prodromus Systematis
Naturalis Regni Vegetabilis. Treuttel & Wurtz, Paris.
One of the greatest botanical works, intended to cover the flowering plants of the
world but eventually included only the dicotyledons. The principles of nomen—
clature used in the work became the basis for the /nternational Code of Botanical
Nomenclature.

Lindley, John (1839-40), Sketch of the Vegetation of the Swan River Colony,
Appendix to the first 23 volumes of Edwards's Botanical Register.

Descriptions of the plants collected by early settlers at the Swan River, Western
Australia.

Lehmann, Johann Georg Christian (1844-1847)[-1848], Plantae Preissianae sive
Enumeratio Plantarum, quas in Australasia Occidentali et Meridionali-occidentali
annis 1830-41 collegit Ludwig Preiss. Meisner, Hamburg.

Almost a preliminary Flora of south west Western Australia, but without keys.
Volume 2 also included many Drummond collections.

Hooker, Joseph Dalton (1855-1860)[-1859], The Botany of the Antarctic Voyage of
H.M. Discovery Ships ‘Erebus’ and ‘Terror’, in the Years 1839-1843, under the
Command of Captain Sir James Clark Ross, Vol. II, Flora Tasmaniae. Reeve,
London.

The botanical results of the expedition’s visit to Tasmania, together with an
important essay on the Australian flora.

Harvey, William Henry (1858-1863), Phycologia Australica, or a History of Aust-
ralian Sea-weeds, 5 vols. Reeve, London.
Colour plates and descriptions of the first major collections of Australian marine
algae.

Mueller, Ferdinand Jacob Heinrich von (1858-1882), Fragmenta Phytographiae Aust-
raliae, Vols I-XII(part I).

A series containing descriptions of many new genera and species, comments on
the status and relationships of many taxa, and notes on distribution.

Figure 5. Joseph Dalton Hooker (1817-1911), author of Flora Tasmaniae (1855-
1860) and of the names of many Australian plants. Portrait by J. H. Maguire, 1851;
reproduced by courtesy of the Director, Royal Botanic Gardens, Kew.

Figure 6. Ferdinand Jacob Heinrich von Mueller (1825-1896), author of over one
thousand papers and books on the Australian flora. Portrait from a photograph taken

in 1865; reproduced by courtesy of the Director, Royal Botanic Gardens, Kew.

Background

Mueller, Ferdinand Jacob Heinrich von [1862-](1860-1865), The Plants Indigenous
to the Colony of Victoria, Vols 1, Il. Government Printer, Melbourne.

The first attempt at a State Flora in Australia.

Bentham, George (1863-1878), Flora Australiensis: a Description of the Plants of the
Australian Territory. Reeve, London.

The standard Australian Flora for over a century.

Spicer, William Webb (1878), A Handbook of the Plants of Tasmania. Walch,
Hobart.

A key to species, together with a systematic checklist and brief distributions,
compiled by a clergyman. Arranged in the system of Flora Australiensis.

Woolls, William (1880), Plants Indigenous in the Neighbourhood of Sydney.
Government Printer, Sydney.

A census of flowering plants and ferns with authorities, arranged in Mueller’s
system.

Tate, Ralph (1880), A census of the indigenous flowering plants and ferns of
extratropical South Australia, Transactions of the Royal Society of South
Australia, 3: 46-90.

A census with references to Flora Australiensis or Mueller’s Fragmenta, and dis—
tribution in eight regions of the State. Arranged in Mueller’s system. A supple—
ment was issued in Vol. 4: 102-111 (1882).

Mueller, Ferdinand Jacob Heinrich von (1882), Systematic Census of Australian
Plants with Chronologic, Literary and Geographic Annotations. Part I, Vas—
culares. Government Printer, Melbourne.

A census arranged in Mueller’s own system which was based on Bentham’s Flora

Australiensis, together with original references, distribution by States, and the
relevant references to Flora Australiensis and Mueller’s Fragmenta.

Bailey, Frederick Manson (1883), A Synopsis of the Queensland Flora, Containing
both the Phaenogamous and Cryptogamous Plants. Government Printer, Brisbane.
A very concise Flora, without keys, arranged in the Bentham and Hooker system
and with a systematic index. Includes the ferns, mosses, lichens, fungi and algae,
with family and generic descriptions and lists of species.

Mueller, Ferdinand Jacob Heinrich von [1886-](1885-1888), Key to the System of
Victorian Plants, 2 parts. Government Printer, Melbourne.

Part I: A key with very short generic and specific diagnoses; includes a list of
aliens.

Part II: A systematic list with distributions, illustrations.

Mueller, Ferdinand Jacob Heinrich von (1889), Second Systematic Census of Aust-
ralian Plants, with Chronologic, Literary and Geographic Annotations, Part I,
Vasculares. Government Printer, Melbourne.

A revision of the Census of 1882.
Tate, Ralph (1890), A Handbook of the Flora of Extratropical South Australia,
Containing the Flowering Plants and Ferns. Education Dept., Adelaide.

An amplified key, covering 1 935 species, together with a list giving distributions.
Arranged in the Bentham and Hooker system.

Background

Moore, Charles & Ernst Betche (1893), Handbook of the Flora of New South Wales.
Government Printer, Sydney.

Keys to families and genera, and amplified keys to species of flowering plants and
ferns with brief generic descriptions. Based on Mueller’s system.

McAlpine, Daniel (1895), Systematic Arrangment of Australian Fungi, together with
Host-Index and List of Works on the Subject. Government Printer, Melbourne.

A census with original references, brief diagnoses, and distributions by States.
Arranged in McAlpine’s own system.

Bailey, Frederick Manson (1899-1902), The Queensland Flora, 6 vols. Diddams,
Brisbane.
Based directly on Flora Australiensis with the addition of species described since
that work and illustrations of some species. An index was issued in 1905.

Rodway, Leonard (1903), The Tasmanian Flora. Government Printer, Hobart.

A very concise Flora with many line drawings, covering 1 286 species (including
aliens), based on the Bentham and Hooker system.

Diels, Ludwig & Ernst Pritzel (1904-1905), Fragmenta phytographiae Australiae
Occidentalis, Botanische Jahrbticher fiir Systematik, Pflanzengeschichte und
Pflanzengeographie 35, 1: 55-662.

The results of extensive work in southern Western Australia, including the des—
cription of many new species.

Dixon, William A. (1906), The Plants of New South Wales. Angus & Robertson,
Sydney.
Keys to families, genera and species of flowering plants and ferns, arranged in the
Bentham and Hooker system.

Black, John McConnell (1909), The Naturalised Flora of South Australia. Privately
published, Adelaide.

The first floristic work written in Australia on introduced plants, concisely
covering 368 ‘species with many line drawings. Arranged in the Bentham and
Hooker system.

Ewart, Alfred James, assisted by James Richard Tovey (1909), The Weeds, Poison
Plants, and Naturalised Aliens of Victoria. Government Printer, Melbourne.
Part I: described and discussed the more important poison plants and weeds;
illustrated.
Part II: a census of 364 naturalised aliens and introduced exotics, with general
distribution, country of origin and date of first record. Arranged in alphabetical

order, but with a supplementary list of families arranged according to the
Bentham and Hooker system.

Bailey, Frederick Manson (1909)[1913], Comprehensive Catalogue of Queensland
Plants, both Indigenous and Naturalised. Government Printer, Brisbane.

A census with authorities and, for some species, supplementary notes; line and
colour illustrations. Arranged in the Bentham and Hooker system.

Background

Rodway, Leonard (1914-1916), Tasmanian Bryophyta, Vol. 1, Mosses; Vol. II,
Hepatics. The Royal Society of Tasmania. (First published as papers in Papers
and Proceedings of the Royal Society of Tasmania).

Synopses of families and higher taxa; keys to species in genera with more than
one species.

Maiden, Joseph Henry & Ernst Betche (1916), A Census of New South Wales
Plants. Government Printer, Sydney.

A systematic census with bibliography of the original publication of each species
and a reference to the description in Flora Australiensis. Arranged in the Engler
system.

Ewart, Alfred James & Olive B. Davies (1917), The Flora of the Northern Territory,
McCarron, Bird, Melbourne.

The only Flora yet issued for the Northern Territory. Adapted from Flora Aust-—
raliensis, with the addition of species described subsequently together with illust—
rations and new locality records. Basically an expanded key, with descriptions
only of the additional taxa. Includes also a tabular key to families.

Black, John McConnell (1922-1929), Flora of South Australia, Parts I-IV; 2nd edn,
Parts I-III, 1943-1952, Part IV revised by E. L. Robertson, 1957, Supplement by
Hansjoerg Eichler, 1965; Part 1, 3rd edn, edited by John Jessop, 1978.
Government Printer, Adelaide.

A concise, original Flora with many illustrations, arranged in the Engler system.
Third edition continuing.

Ewart, Alfred James (1930)[1931], Flora of Victoria. Government Printer,
Melbourne.

A concise, original Flora with many line drawings, including about 2 200 indig—
enous species and 500 naturalised species. Arranged in the Engler System.

Gardner, Charles Austin (1930-1931), Enumeratio Plantarum Australiae Occidentalis:
a Systematic Census of the Plants Occurring in Western Australia. Government
Printer, Perth.

The first census of the Flora of Western Australia, arranged in the Engler system.

Cleland, John Burton (1934-1935), Toadstools and Mushrooms and Other Larger
Fungi of South Australia. Government Printer, Adelaide.

Keys to families, genera and species, with concise descriptions and many illustra—
tions. Covers Basidiomycetes, Gasteromycetes, Heterobasidiae and Myxo-
mycetes. Classification modified from C. Rea (1922) and P. Clausen in Engler
and Prantl (1928), some groups based on other authors.

Lucas, Arthur Henry Shakespeare (1936-1947), The Seaweeds of South Australia,
Part I, Jntroduction and the Green and Brown Seaweeds; Part II, The“Red
Seaweeds (completed by F. Perrin, H. B. J. Womersley & J. R. Harris).
Government Printer, Adelaide.

Keys, descriptions and black-and-white illustrations; arranged in the system of
De Toni.

Gardner, Charles Austin (1952), Flora of Western Australia, Vol. 1, part 1,
Gramineae. Government Printer, Perth.
The only part published of a proposed State Flora.

Background

Blackall, William Edward & Brian John Grieve (1954-1980), How to Know Western
Australian Wildflowers, Parts I-IV, IIIA; Parts I-III reprinted in one volume,
1974. University of Western Australia Press, Perth.

Illustrated keys to the flora of southern Western Australia.

Curtis, Winifred Mary (1956-1979)[-1980], The Student’s Flora of Tasmania, Parts
1-4, 4A. Government Printer, Hobart.

A concise Flora with many line drawings. Arranged in the Bentham and Hooker
system.

Flora of New South Wales (1961-1978). Government Printer, Sydney. Published as a
Flora Series of Contributions from the New South Wales National Herbarium,
and from 1971 as Flora of New South Wales.

An incomplete and now discontinued series, by various contributors, on a mono-
graphic basis. Based on the Engler system.

Willis, James Hamlyn (1962-1972)[1973], A Handbook to Plants in Victoria, 2 vols.
Melbourne University Press, Melbourne.

A very concise State Flora in the form of an amplified key.

Beadle, Noel Charles William, Obed David Evans & Roger Charles Carolin (1962)
[1963], Handbook of the Vascular Plants of the Sydney District and Blue Moun-
tains. Privately published, Armidale.

Contains keys to families, genera and species, with generic diagnoses; includes
Pteridophyta, Gymnospermae and Angiospermae. Systematic arrangement of fam-
ilies modified from Hutchinson (1926).

Burbidge, Nancy Tyson (1963), Dictionary of Australian Plant Genera: Gymno-
sperms and Angiosperms. Angus & Robertson, Sydney.
For each genus includes important bibliography, general distribution and number
of species.

Beard, John Stanley (ed.) (1965), Descriptive Catalogue of West Australian Plants;
2nd edn 1970, as West Australian Plants. Society for Growing Australian Plants,
Sydney.

A census of the flowering plants of Western Australia with brief notes on the
habit, habitat and distribution, based on the collections at the Western Australian
Herbarium.

Burbidge, Nancy Tyson & Max Gray (1970), Flora of the Australian Capital Terri-
tory. Australian National University Press, Canberra.
A concise illustrated Flora set out as amplified keys, arranged in the Engler
system.

Beadle, Noel Charles William (1971-1976), Student’s Flora of Northeastern New
South Wales, Parts I-III. University of New England, Armidale.
A concise systematic Flora in the form of amplified keys, together with generic
descriptions. Arranged in a modified Hutchinson system.

Beadle, Noel Charles William, Obed David Evans & Roger Charles Carolin (1972),
Flora of the Sydney Region. A. H. & A. W. Reed, Sydney.
Revised, enlarged and illustrated edition of Beadle et al., (1962).

Background

Chippendale, George McCartney (1972), Check list of Northern Territory plants,
Proc. Linn. Soc. New South Wales 96: 207-267.

A census with abbreviated distributions, arranged in the Engler system.

Weber, William A. & Clifford M. Wetmore (1972), Catalogue of the Lichens of Aust-
ralia, exclusive of Tasmania. Cramer, Germany.
An alphabetical list with references, synonyms and distributions in States.

Scott, George A. M., Ilma Stone & Celia Rosser 978); The Mosses of Southern
Australia. Academic Press, London.
The mosses of the region described or diagnosed, tgettieg with keys and many
illustrations.

Costin, Alec B., Max Gray, Colin Totterdell & Dane Winbush (1979), Kosciusko
Alpine Flora. CSIRO & William Collins, Melbourne.

Keys and descriptions for the vascular flora, together with descriptions of the
plant communities and history of the region. Copiously illustrated in colour.
Arranged in the Engler system.

Filson, Rex Bertram & Roderick W. Rogers (1979), Lichens of South Australia.
Government Printer, Adelaide.
Keys and diagnoses for fruticose and foliose lichens to specific level, and for crus—
tose lichens to generic level.

Catcheside, David Guthrie (1980), Mosses of South Australia. Government Printer,
Adelaide.
Keys and descriptions, with line and colour illustrations. Arranged in the system
of M. Fleischer.

Green, John William (1981), Census of the Vascular Plants of Western Australia.
Western Australian Herbarium, South Perth.
A list of the native and naturalised flora of the State, with families arranged in the
Engler system.

Jessop, John Peter (ed.) (1981), Flora of Central Australia. A. H. & A. W. Reed,
Sydney.
A concise Flora of the arid regions of Australia, arranged in the Engler system.

Cunningham, Geoffrey McIver, William Edward Mulham, Peter Lindsay Milthorpe &
John Holland Leigh (1981), Plants of Western New South Wales. Soil Conser-
vation Service of New South Wales & Government Printer, Sydney.

Describes over 2 000 species, mostly illustrated in colour or black and white, with
keys to some groups. Families arranged in the Engler system, the genera and
species alphabetical.

Background

References

Anonymous (1968), Proposal to establish a Biological Survey of Australia. Flora and
Fauna Committee of the Australian Academy of Science.

Beard, J. S. (1968), Towards a new Flora Australiensis, Austral. J. Sci. 31: 89-90.
Bentham, G. (1863-1878), Flora Australiensis, Vols. 1-7. Reeve, London.
Blake, S. T. (1960), A New Flora of Australia, Austral. J. Sci. 23: 173-176.

Burbidge, N. T. (1951), Select List of Publications in Systematic Botany Available in
Australia, CSIRO Division of Plant Industry, Divisional Report No. 14.

Burbidge, N. T. (1963), Dictionary of Australian Plant Genera: Gymnosperms and
Angiosperms. Angus & Robertson, Sydney.

Burbidge, N. T. (1974), Progress towards a new Flora of Australia, CS/RO Division
of Plant Industry, Annual Report 1973, 31-34.

Burbidge, N. T. (1978), Plant Taxonomic Literature in Australian Libraries. Aust—
ralian Biological Resources Study, Canberra.

Churchill, D. M., Muir, T. B. & Sinkora, D. M. (1978), The published works of
Ferdinand J. H. Mueller (1825-1896), Muelleria 4: 1-120.

Cronquist, A. J., (1981) An Integrated System of Classification of Flowering Plants.
Columbia University Press, New York.

Daley, C. (1927), The history of Flora Australiensis, Victorian Naturalist 44: 63-69,
90-100, 127-138, 153-165, 183-187, 212-221, 271-278.

Hartley, W. (1947), The functions of a Commonwealth Herbarium, Australas. Herb.
News 1: 28-31.

Jessop, J. P. (ed.)(1981), Flora of Central Australia. A. H. & A. W. Reed, Sydney.
Ride, W. D. L. (1978), Towards a National Biological Survey, Search 9: 73-82.

Ride, W. D. L. & McCusker, A. (1978), The extent and nature of programs in bio-—
logical survey conducted primarily by State museums and herbaria, in Australian
Biological Resources Study 1973-78. AGPS, Canberra.

Ross, J. H. (1976), An analysis of the flora of Victoria, Muelleria 3: 169-176.
Stafleu, F. A. (1967), The Flora Australiensis, Taxon 16: 538-542.

Waterhouse, D. F. (1978), Report and recommendations made by the Interim Coun—
cil of the Australian Biological Resources Study, in Australian Biological Resour-
ces Study 1973-78. AGPS, Canberra.

THE AUSTRALIAN FLORA : ITS ORIGIN AND
EVOLUTION

B. A. Barlow

The plants of Australia — a unique flora?

From the time of their first discovery and study by European naturalists, the plants of
Australia have been noted for their uniqueness, almost as curiosities of the Earth’s
vegetation. This feeling is reflected by the very name, Botany Bay, of Captain James
Cook’s landing site of 1770 where Banks and Solander enthusiastically made the first
intensive plant collection of the continent. For the next half-century or so, the pages
of botanical journals such as Loddiges’ Botanical Cabinet and Curtis’s Botanical
Magazine were dominated by descriptions of strange new plants introduced into cul—
tivation from New Holland. Even today the seemingly unusual features of the Aust—
ralian flora are promoted, especially for the purposes of national and international
tourism.

The ‘uniqueness’ of the Australian flora is of course a matter of interpretation.
The flora is certainly unique in the sense that a very high proportion of its species are
endemic to the continent. It is also distinguished by the fact that two large genera,
Eucalyptus and Acacia, between them dominate almost all the plant associations of
the continent. Eucalyptus has a very limited natural occurrence outside Australia,
and most of the Acacia species in Australia belong to the phyllodinous group which
is also almost confined to the region. In a broad sense, then, the special character or
uniqueness of the Australian flora is generally expressed in terms of plant communi-—
ties dominated by Eucalyptus and Acacia, and including other genera and species
which do not occur anywhere else.

At a higher taxonomic level the uniqueness of the Australian flora virtually
disappears. Almost all the angiosperm families in Australia occur widely elsewhere.
Conversely, almost all the larger families of the world occur in Australia. In this
sense, the Australian flora is simply a typical part of the world flora and the special
character of Australian plants at lower taxonomic levels has to be explained in terms
of the geographical and climatic conditions under which the continental flora has
developed.

The early phytogeographers, floristic ‘elements’,
and the invasion theory

A century of J. D. Hooker

It is not surprising that the recognition of a unique character in the Australian
flora quickly led to questions and speculation on the origin of the flora. Since Aust-
ralia is an island continent, how did this remarkable flora get here? Where gid it
come from, and when? The first major work on this topic, which provided the prime
impetus for theories on the origin and evolution of the flora for a century to follow,
nearly coincided, in fact, with the long-awaited publication of Darwin’s Origin of
Species. This work, by the eminent English botanist J. D. Hooker, took the form of
an introductory essay to a Flora of Tasmania (Hooker, 1860). Hooker had an excel—
lent general knowledge of the entire world flora, and had already acquired a detailed
knowledge of the floras of India and Africa. In the introductory essay he analysed the

Origin and Evolution

floristic records not just of Tasmania, but of the whole of Australia. He integrated the
unpublished records known to him with the published ones in a classical phyto-
geographical analysis in which the Australian flora was broken down into ‘elements’
based on taxonomic affinities with the floras of other regions. For example, Hooker
pointed out that many Indian plant genera were represented in northern Australia, in
comparable monsoon habitats, and that Malaysian rainforest genera were represented
in the appropriate habitats of tropical eastern Australia. In temperate south-eastern
Australia he recognised that the floras of cool rainforest and alpine habitats shared
genera with both New Zealand and temperate South America. At the family level, he
noted common representation in the floras of south-western Australia and South
Africa.

Hooker thus identified three elements in the Australian flora, and it is not sur—
prising that there is a strong ecological as well as taxonomic distinction between
them. These were (1) an autochthonous (Australian) element consisting mainly of
endemic or almost endemic taxa occupying temperate open forest, woodland and
heath habitats and mainly xeromorphic in character, (2) an Indomalayan element
represented in tropical and subtropical rainforest and monsoon habitats and showing
taxonomic affinity with plants of similar habitats in the Indomalayan region, and (3)
an Antarctic element represented in temperate rainforest and alpine habitats, char—
acterised by Nothofagus and showing taxonomic affinity with plants of New Zealand
and temperate South America in particular. Hooker also noted the presence of cos—
mopolitan plant groups, mostly herbaceous, and widely distributed within Australia. It
can hardly be said that Hooker drew any firm conclusions as to the actual history of
the Australian flora, but his phytogeographical analysis was certainly the basis of the
theory generally accepted for the next century. This theory was based on the concept
of colonisation of the Australian land mass by separate invasions of different floras,
perhaps at different times.

The ‘invasion’ theory depended on several assumptions. First, it was assumed that
the earth’s geography was fixed, so that Australia’s position relative to other contin—
ental land masses had not changed. It was noted, however, that changes in sea level
and/or tectonic movements in the earth’s crust could have created land bridges be—
tween Australia and other regions. Secondly, it was recognised, from the comparable
plant associations in Australia and elsewhere, that whole plant communities had
migrated together. In fact, there was relatively strong resistance to the idea of indi-
vidual plant migration through long-distance dispersal. Thirdly, it was assumed that
the flowering plants could not have arisen in Australia, and must therefore have been
established in Australia as colonisers from outside. Reasons for this belief were rarely
given, and one suspects that it may simply have been concluded that Australia was
too insignificant a place to have been the ancestral home of the angiosperms.

The invasion theory for the origin of the Australian flora was compatible in some
respects with the theories of the time for the origin of the Australian vertebrate
fauna, dominated as it is by marsupials. The theories thus gained some strength from
mutual support. For plants, the invasion theory was generally developed along the
following lines.

The first angiosperm colonisers probably entered Australia in Cretaceous times
(see Table 2). The fossil record showed that even though this may have been rela—
tively early in the history of the angiosperms, the major flowering plant families had
already differentiated. During this time Australia was connected to Asia by a much
more extensive land bridge across what is now the Indonesian Archipelago, and the
first angiosperm invasion probably came, therefore, from the north-west.

Origin and Evolution

The Indomalayan land bridge was thought to have broken up at the end of the
Cretaceous period, over 50 million years ago (50 m.y. BP), leaving the Australian
angiosperm flora of the time to evolve in isolation. Since the previous vegetation of
the continent consisted of gymnosperms and lower land plants, the first angiosperm
flora probably evolved under conditions of low competition, and therefore of low
selection pressure, and underwent a period of rapid evolutionary diversification to
occupy the broad spectrum of available habitats. Radiation in isolation thus gave rise
to the diverse and unique autochthonous element with its high endemism. The aut—
ochthonous element came to be thought of as the oldest component of the Australian
flora, and has been commonly referred to as the Palaeoaustralian element by biogeo—
graphers of the 20th century.

The Indomalayan and Antarctic (or Subantarctic) elements were thought of as the
results of later angiosperm invasions of the region. The later invaders would have
encountered an established and adapted angiosperm flora, and would have been con—
fined by competition to habitats to which they were already well adapted. These two
elements have thus persisted with much less change and, as a consequence, show a
more obvious taxonomic affinity with their ancestral floras in other areas. The Indo—
malayan element was of course seen as the result of a later migration from the trop—
ical north and west, perhaps over the same land bridge as existed for the first
invasion. The Antarctic element was thought to have arrived over a land bridge from
the south-east, perhaps now represented by the South Tasman Ridge and Macquarie
Rise, at a time when Antarctica was free of an ice-cap and extensively vegetated by a
southern temperate flora.

This interpretation of the history and relationships of the Australian flora was fol—
lowed, in whole or in part, by a succession of authors. Tate (1888) applied it particu—
larly to an analysis of the arid zone flora. Diels (1906), who had collected in Western
Australia under the sponsorship of Engler, developed this approach rather precisely
and concluded that the South West Botanical Province of Western Australia was the
centre of origin of the Australian element. Perhaps the first author who seriously
attempted to correlate botanical and geological histories of the Australian region,
however, was Andrews (1916), who accepted the phytogeographical divisions of the
flora and was the first to suggest that soil properties may have a bearing on distribu—
tion of Australian floristic elements. He suggested that scleromorphy, which charact—
erises much of the Australian element, was an adaptive response to low levels of soil
nitrogen and calcium. This idea has been extended by a number of later authors and
is further discussed below.

Schwarz (1928) produced a phytogeographical analysis of the northern Australian
flora and recognised most of the elements accepted by earlier authors with the excep-
tion of the Antarctic element. Like Hooker (1860), he drew attention to the close
similarity at the generic and even specific level of some plant associations of India
and northern Australia. This similarity has subsequently been documented by Specht
(1958) and has assumed an important place in current biogeographical theories (see
below).

The integration of soil and climatic data with plant distribution and evolution was
further developed by Crocker and Wood (1947). Their attention, however, was focus—
sed on the Australian element, its Tertiary history and the Recent cycles of aridity
which have influenced the evolution and distribution of an arid zone flora. This topic
is also discussed in more detail below.

The phytogeographically-based invasion theory culminated in the monumental
work of Burbidge (1960) on the phytogeography of the Australian region. As a result
of her very detailed analysis of the floristic composition of Australia’s major vegeta—

Origin and Evolution

tion zones, she accepted the idea of distinct floristic elements. She accepted that the
autochthonous element may have been derived from an immigrant flora although she
suggested alternatively that it may have ‘developed from a pre- or early Cretaceous
(Australian) flora of an unknown type’. She described north-east Queensland and
Tasmania as important ‘portals’ for the Indomalayan and Antarctic elements respec—
tively. While she accepted the idea of a later invasion of an Indomalayan flora from
the north, and of an Antarctic element from the south, she did express doubts about
the existence of a former land bridge southwards from Australia.

The impact of the Smith- White school of karyoevolution

The prolific and pioneering karyological studies of Smith-White (1948a, 1948b,
1950, 1954a, 1954b, 1955, 1959) generated theories of genomic evolution which
made a major contribution to the invasion theory. His work covered major families of
the flora, and particularly of the Australian element, including Myrtaceae, Rutaceae
and Epacridaceae. Contemporary studies by Smith-White’s students extended to
Proteaceae (Ramsay, 1963), Casuarinaceae (Barlow, 1959), Goodeniaceae (Peacock,
1963), Loranthaceae (Barlow, 1963) and Lobeliaceae (James, 1963). At that time
Smith-White accepted the idea that the angiosperms originated outside Australia, and
that the Australian flora was derived from a number of immigrant stocks. He strongly
supported the ideas that an ancient palaeoaustralian element had evolved in isolation
under conditions of low selection pressure, and that the Indomalayan element was
derived from a later immigration from the north. He was less inclined to accept the
idea of a major Antarctic element, and particularly of an Antarctic land bridge, but
did postulate that the alpine flora was derived partly by long-distance dispersal from
South America and Antarctica.

In support of this theory, Smith-White (see especially 1954b, 1959) drew atten—
tion to recurring patterns of chromosome number variation in several of the families
mentioned. In the woody families Myrtaceae, Rutaceae, Proteaceae, Epacridaceae
and Casuarinaceae, and to a lesser extent in the herbaceous families Goodeniaceae
and Lobeliaceae, he pointed out that groups which were endemic to Australia, or
nearly so, exhibited considerable diversity in basic haploid chromosome number when
compared with related groups distributed beyond the Australian region. The situation
in families Myrtaceae and Rutaceae is summarised in Table 1. The patterns of change
in different families were different, but it was generally found that different basic
haploid numbers characterised genera rather than species. Within genera (or compar-—
able supra-specific groups) basic numbers were usually constant but polyploidy occur—
red, rarely in the case of some woody families and frequently in the herbaceous ones.

Smith-White (1954b, 1959; see also review by James, 1981) thus postulated that
in the evolution of these families an early genomic instability was later replaced by an
extreme stability. Following the initial angiosperm radiation, outside Australia, in
which the chromosome numbers of the various angiosperm families were established,
there was a secondary cycle of change in the differentiating palaeoaustralian element
after the first angiosperm colonisation of Australia. In this phase of expansion, under
conditions of low competition and reduced selection pressures, ‘genetic experiments,
including experiments in structural change and chromosome number’ would have
been favoured. The karyological data were thus consistent with the phytogeographical
theory for the origin of a palaeoaustralian element. During later phases in the history
of the flora, including the entry of the Indomalayan element and the evolutionary
responses to Tertiary climatic changes, only a third-order cycle of genomic evolution
would have been possible. In this phase, under conditions of strong competition and
high selection pressures, drastic genomic rearrangements were not tolerated and

Origin and Evolution

genomic evolution was limited mainly to euploid changes, within established genera,
on basic chromosome numbers which were now fixed.

This mass of consistent karyological data undoubtedly supported the invasion
theory at a time when emerging geophysical data were starting to cast greater and
greater doubts upon it. The subsequent collapse of the three-element, three-invasion
theory was thus a rather dramatic event in the history of phytogeography in Aust—
ralia. It is noteworthy that a relatively simple reinterpretation of the karyological
data, in terms of current principles of population genetics and by the original authors
of the data, now adds an important element of detail to current ideas on the origin of
the Australian flora.

The challenge to the invasion theory

There seems to have been little opposition, among the earlier phytogeographers,
to the three-element invasion theory. Gardner (1944) opposed it only in the sense
that floristic elements could not be distinguished at the family level. It seems that
only Herbert (1932, 1935, 1950, 1960, 1964, 1967) consistently denied the theory on
floristic and ecological grounds, although he was supported in part by Beadle (1966).
Herbert argued the existence of an ancient palaeotropical flora which was already
established in Australia at least as far back in time as the early Mesozoic. Through
comparisons between modern plant associations, in respect of distribution and com—
position, he argued that floristic ‘elements’ were merely the result of climatic and
edaphic ‘sifting’ of the ancestral flora. He strongly opposed the idea of migration

Table 1. Distribution of chromosome numbers in the Myrtaceae and Rutaceae (modi—
fied from Smith-White, 1959), shown as number of species for subfamilies, tribes and
subtribes. Asterisks (*) indicate groups endemic to Australia or nearly so.

Gametic chromosome number

Goer /ee Saeco Opel ie Due Sie Ae Oma Saul One? 2.

32 27 44
36
54
MYRTACEAE
Chamelaucoideae Chamelaucinae* By ik yO) 10 1 2 1
Other Chamelaucoideae 4
Leptospermoideae 89 7
Myrtoideae 6 6
RUTACEAE
Rutoideae Boronicae* 2 2 10 sy tt PP iweIEY it itr
Other Rutoideae 2 11
“a
Aurantoideae 44 14
Flindersioideae 4 2

Origin and Evolution

across land bridges, pointing out the need for suitable habitats within the bridge for
migrating species and emphasising the sifting effect which such bridges would have
on community structure. The current theories of Australian biogeography to some
extent vindicate Herbert’s views.

The main weakness in the invasion theory was of course the lack of geophysical
evidence for the required land bridges. A Cretaceous land connection between Aust—
ralia and south-east Asia was hypothetical, supported primarily by the existence of
the present-day Indonesian Archipelago. The only evidence for an Antarctic bridge
was the presence of submarine rises to the south and east of Australia, but there is
nevertheless a broad gap of deep ocean between Australia and Antarctica. The other
problem, discussed in more detail below, was that the fossil record of angiosperms in
Australia, meagre though it was, produced no evidence that the autochthonous ele—
ment was older than the Indomalayan or Antarctic. Assemblages containing plants of
the latter stocks were recorded from widely dispersed sites in Australia extending
back in time to the early Tertiary period, thus tending to support the idea of an
ancient mosaic of vegetation as Herbert had envisaged it.

Plate tectonics and biogeography

Continental displacement and its implications

Continental displacement (continental drift) has existed as a valid explanation of
world vegetation patterns for some time, and was preferred by such plant geographers
as Cain (1944) and Good (1947). On theoretical grounds these authors were strongly
opposed to long-distance dispersal and were attracted to the idea that whole floras
could be exchanged across united continental masses. Nevertheless the theory re-
mained in general disfavour primarily because it involved an element of circular
reasoning in that the main supporting arguments came from plant distributions. More
recently, discoveries of mid-ocean ridges, sea-floor spreading and palaeomagnetism
have provided a geophysical basis for the lateral displacement of continental plates
and have led to a ready acceptance of the theory of plate tectonics in biogeographical
analysis.

For a land mass like Australia, which is relatively isolated geographically, the
implications of continental displacement are very great. An immediate explanation is
apparent, for example, for the existence of closely similar plant communities, with
identical ecological relationships, in regions now separated by large ocean barriers.
We can explain how a tree genus can occur in widely disjunct regions with the same
genera of understorey plants in both regions, and with the same genera of parasites
and predators. There is a general consensus that the current theory for the origin of
the Australian flora, with its supporting evidence from the fossil record and from pal—
aeoclimatic data, is quite consistent with the current models, from purely geophysical
data, of the geographical history of the continental masses.

A brief account of the physical basis and biological consequences of continental
displacement is given below, as a preamble to a general account of current theory on
the origin of the Australian flora.

The theory of plate tectonics

The theory of plate tectonics, which forms the basis of all palaeogeography and of
most modern biogeography, is quite simple and now lies very much in the realm of
popular science. Its basis is the observation that earthquakes occur mostly in linear
zones on the earth’s surface, and that these zones enclose areas in which earthquakes
do not occur. The aseismic regions of the earth’s crust are called plates, and it is now

Origin and Evolution

known that it is the relative motion between these plates which causes deformation
and earthquakes at their margins. A single plate often comprises both oceanic and
continental regions, and the earth’s surface is entirely covered by crustal plates in
motion relative to each other.

There are three types of plate boundary. First, two plates may be moving apart.
Material from below the crust upwells, often as massive outpourings of lava, and adds
to the margins of the plates forming a ridge of young crustal material. Secondly, two
plates may be colliding, in which case one plate may be thrust under the other,
forming a deep trench, with the crustal material sinking back into the earth’s mantle.
Thirdly, two plates may slide past each other without formation or destruction of
plate material, forming transform faults. Folded mountain belts parallel with the mar—
gins of plates are often the results of collisions, or simply ‘bow waves’ of continental
movement.

The consequence of these processes is that through geological time the relative
positions of the continents have changed as their plates have moved. In particular,
there is evidence that at one or more times in the past the continents have been
grouped into one or two supercontinents, and that these stages have been followed by
rifting and separation of entire continental masses. Complementary evidence is avail—
able from a number of sources, including matching of continental margins and mid-
ocean ridges, tracing of polar wandering paths from palaeomagnetic studies, and the
actual measurement of the rate of new crust formation.

Geography of the past

There is now general agreement on Australian palaeogeography, with current
studies mainly resolving questions of detail. In the Jurassic (see Table 2) the southern
supercontinent comprised what are now South America, Africa, Madagascar, India,
Australia, Antarctica and New Zealand (Fig. 7). Rifting began in the middle/late
Mesozoic with a separation of South America and Africa, progressing from north to
south. Other relatively early separations included Madagascar and India, and also the
late Cretaceous separation from Australia of New Zealand and the Lord Howe Rise.
By early Tertiary time the southern lands may have had a configuration like that
shown in Fig. 8, with Australia still joined to Antarctica on a broad front, and South
America and Antarctica retaining their narrow connection.

Possible geographical relationships between Australia and Antarctica during the
Tertiary period are illustrated by Crook (1981) and Kemp (1978, 1981). Rifting was
initiated in the Palaeocene (Fig. 9), and by the middle Eocene had formed a wide
gulf opening westwards (Fig. 10). Crook (1981) suggested that the first opening was a
narrow seaway which completely separated the two land masses except for a possible
residual contact at the south-western corner of Australia. A more widely accepted
view, however, is that Australia and Antarctica remained joined by the South Tasman
Rise (Fig. 10), and that the connection probably persisted until late Oligocene time,
when Australia was entering lower latitudes (Figs 11, 12). The narrow land connec—
tion between South America and Antarctica was also maintained at least until this
time (Jardine & McKenzie, 1972).

The northward movement of Australia continued through Miocene time (Fig. 13),
and subsequently, at rates as high as 7.4 cm per year (Weissel & Hayes, 1974). The
northern margin of the Australian Plate at that time was formed by what is now
southern New Guinea. In the mid-Miocene, about 15 m.y. BP, the Australian Plate
came into contact with the Sunda island arc system, forming the present New Guin—
ean land mass and possibly also creating a relatively continuous land connection with
south-east Asia (see page 46 for further details). The continued northward movement

PLEISTOCENE

PLIOCENE

MIOCENE

OLIGOCENE

EOCENE
PALAEOCENE

NEOGENE

WwW
re
WW
Oo
e)
WW
<x
—J
<
a

Maastrichtian

Campanian

Santonian
Coniacian

Turonian
Cenomanian

jae Barremipnsaesaeeeees |
Siaeimin 3

Table 2. Geological time scale since the Jurassic. (After Raven & Axelrod, 1974;
reproduced by permission from Ann. Missouri Bot. Gard. 61: 559)

SENONIAN

CO es ©) Te GG) ee eT]

Origin and Evolution

of the Australian plate has subsequently produced a disjunction from the Sundaland
plate (Specht, 1981c), recreating an ocean barrier between the two.

Climates of the past

Palaeoclimates have been determined partly by palaeogeography and partly by the
global climate, particularly the extent of polar ice-caps (Kemp, 1978). There is an
element of circularity in the procedure for measuring palaeoclimates in the sense that
palaeotemperatures, which are used to explain plant distribution, are determined from
analysis of fossils, but these palaeotemperature data are determined mainly from oxy-—
gen-isotopic analysis of planktonic foraminifera and refer to the sea surface and bot—
tom temperatures. They are thus remote from terrestrial fossil data, yet they do have
considerable bearing on the interpretation of terrestrial palaeoclimates.

At the beginning of the Tertiary period, seas in high latitudes were much warmer
than they are now, perhaps with surface temperatures of 18—20°C at latitudes higher
than 60°S (Kemp, 1978). There is no evidence of an ice-cap on Antarctica at that
time. The polar high pressure system would have been much reduced in intensity and
extent, and a broad zone of westerly winds would have influenced southern Australia
(Fig. 9). Further north, weak and erratic circulation patterns associated with warm
sea surfaces would have resulted in deep inland penetration by rain-bearing winds.
These conditions may have persisted through the Eocene, with water temperatures on
the Campbell Plateau dropping from 20°C to 10°C and some glacial activity being

Jurassic

Figure 7. Fit of the Gondwana continents during the Jurassic, prior to breakup.
(From Raven & Axelrod, 1974, after Smith & Hallam, 1970; reprinted by permission
from Ann. Missouri Bot. Gard. 61: 540)

Origin and Evolution

initiated in Antarctica (Fig. 10). However even these conditions were warmer than
those of the present. The lowering of temperatures would have been associated with a
lowering of precipitation.

The final separation of Australia and Antarctica in the Oligocene initiated cir—
cumpolar oceanic circulation, reducing heat transport from equator to pole and
increasing the temperature gradient between those regions (Kemp, 1978). Sea surface
temperature of the Campbell Plateau dropped to 6-7°C and probably nearly to freez—
ing near Antarctica. The westerly wind systems would have extended further north—
wards as a result of these developments (Figs 11, 12). A simple explanation of the
influence of conditions in Antarctica on the climate of Australia is given by Kemp
(1981).

Figure 8. Reconstruction showing early Tertiary configuration of Gondwanan
continents. Dots show active plate boundaries at that time. (From Jardine &
McKenzie, 1972; reprinted by permission from Nature 235: 22. © 1972, Macmillan
Journals Ltd.)

Middle Palaeocene 58m.y.

_——
Areas covered by \ ae
marine incursions J C S ~

No evidence
for ice-cap

(South Pole) ar

AUS 4/54

Figure 9. Palaeogeographical reconstruction of the Australian region for the middle
Palaeocene (58 m.y. BP), with tentative atmospheric palaeocirculation indicated by
heavy arrows. Shallow seas transgressing the present continental margin are shown in
stipple. (From Kemp, 1978; reprinted by permission from Palaeogeography,
Palaeoclimatology, Palaeoecology, 24: 180)

Middle Eocene 45m.y.

~
N
>
OS *
ES Areas covered by oe \ )
morine incursions > \ 4
) NS
/
/
7
7
/
i Cx
/ — i »S
j Irregular circulation \ I] 708 )

patterns

aly
ANE

Figure 10. Palaeogeographical reconstruction of the Australian region for the middle
Eocene (45 m.y. BP), with tentative atmospheric palaeocirculation shown by heavy
arrows. Transgressive seas shown in stipple. (From Kemp, 1978; reprinted by
permission from Palaeogeography, Palaeoclimatology, Palaeoecology, 24: 184)

Early Oligocene 37m.y

Increase in ice-cover
no sea-level ice known

4} (South Pole) \

Figure 11. Palaeogeographical reconstruction of the Australian region for the early
Oligocene (37 m.y. BP), with tentative atmospheric palaeocirculation shown by heavy
arrows. Transgressive seas shown in stipple. (From Kemp, 1978; reprinted by
permission from Palaeogeography, Palaeoclimatology, Palaeoecology, 24: 192)

Late Oligocene 30m.y. ‘

=
ul) Des J Xs
jin I

iin of ice-cap
unknown ‘i

+ (South Pole)

Figure 12. Palaeogeographical reconstruction of the Australian region for the
Oligocene (30 m.y. BP), with tentative palaeocirculation patterns shown by heavy
arrows. Transgressive seas shown in stipple. (From Kemp, 1978; reprinted by
permission from Palaeogeography, Palaeoclimatology, Palaeoecology, 24: 193)

F
—— Late Miocene 7m.y.

oles

aA Ss

2
ay
re

/
\

ee Dp om :
.

A ( ge :
ie y \ \\)

Figure 13. Palaeogeographical reconstruction of the Australian region for the late
Miocene (7 m.y. BP), with tentative atmospheric palaeocirculation patterns shown by
heavy arrows. Transgressive seas shown in stipple. (From Kemp, 1978; 1eprinted by
permission from Palaeogeography, Palaeoclimatology, Palaeoecology, 24: 198)

Origin and Evolution

By late Miocene time the Antarctic ice sheet had reached its present dimensions
(Kemp, 1978). Atmospheric circulation increased in intensity, perhaps exceeding that
of the present. In parts of Australia levels of precipitation would have fallen and the
first onset of a general aridity may have occurred (Kemp, 1978; Bowler, 1981; see
below). There is evidence of an ice-surge at the Pliocene boundary, about 5 m.y. BP
(Kemp, 1978; Trusswell & Harris, 1981). This would have produced a lowering of
temperatures in Australia and an increase in dry anticyclonic circulation. A Pliocene
warming followed, then a second cooling in the late Pliocene. These cycles were part
of a trend towards cycles of aridity which began in the middle Miocene and have
become increasingly frequent up to the present time (Specht, 1981c). Late Cainozoic
climates in Australia are discussed in more detail below.

Biological consequences of plate tectonics

The effects which continental displacement have had on plant distributions are
obviously related to the dispersibility of the plants. Angiosperm dispersibility natu-
rally covers a wide spectrum, but a surprising number of plant geographers have
taken a narrow view of the effective limits of plant dispersibility. For example, the
Hawaiian Islands have never been close to continental land and, since their origin,
must have been colonised entirely through long-distance dispersal (Carlquist, 1966;
Baker, 1967). There is no physical evidence to support the view that land bridges
have been involved although a number of workers, including Croizat (1952) and van
Steenis (1963), have argued their former existence. At least 272 immigrant ancestral
species are required to explain the 2 000 indigenous species in the islands today
(Fosberg, 1948).

At the other extreme are families or genera with very limited dispersibility, for
which any zone of unfavourable territory represents an absolute migration barrier.
They often prove to be strongly continental in their distributions. Groups close to this
end of the spectrum include the Proteaceae (Johnson and Briggs, 1975), Nothofagus
and the southern gymnosperms (Preest, 1963) and the Loranthaceae (Barlow, 198 1a).
In the latter case the family has not even recolonised Tasmania (see below), and
Keast (1958) has shown that although the seeds are bird-dispersed the likely dispersal
range is very small. Similarly, species dispersal for this family across Torres Strait has
probably been mainly over continuous land (Barlow, 1972).

For many taxa with high dispersibility, the positions of the continents have little
effect on distribution, and plate tectonics may be unimportant. Highly dispersible
groups are well represented among coastal habitats and a number of cosmopolitan
families are common in such habitats. For groups of moderate dispersibility, changes
in the proximity of drifting land masses can obviously make or break migration
routes. For groups of low dispersibility, migration only over continuous land can be
postulated.

These and other consequences of plate tectonics have been well summarised by
McKenna (1972). Epicontinental flooding on a world wide scale may have occurred
in lowlands due to water displacement at times of spreading maxima, thus causing
mass extinction which would have been followed by recolonisation and adaptation at
times of reversal. Indeed there was a great spread of epeiric seas in the Australian
region associated with the Cretaceous fragmentation of Gondwanaland (Coleman,
1980). The effects of continental rifting would be gradual but quite profound, with
the first stage little more than a major extension of coastline (cf. the Red Sea). With
widening of the rift, however, continental climates would be moderated and changes
in oceanic circulation could lead to general changes in climate. Climatic changes
would also be predicted where a drifting block moved through different climatic

Origin and Evolution

zones. These processes would obviously result in massive
and thus in adaptation, extinction and/or migration. Separa
would also be a major cause of disjunct distributions and
pairs of taxa.

changes in plant habitats
tion of continental blocks
the evolution of vicarious

Similarly, collision between continental plates would ev
an abrupt biological response. Ecologically,
new upland or alpine habitats created, again
colonisation respectively. Floristically,
would commence with colonisation by

oke a gradual rather than
marine habitats would be destroyed and
leading to extinctions and adaptation and
exchange between the approaching floras

y the more highly dispersible taxa while the
blocks were still well apart. Competition and adaptation would thus occur pro-

gressively even before contact, so that a massive ‘invasion’ of one biota into the area
of another might be unlikely to occur as a single event. Upon actual contact, a fil-
tered migration along a corridor might occur, followed by general exchange rent a
broad front when contact became extensive, and by colonisation of the new habitats
created. Given the time periods involved, competition for niche space could remain
high throughout a collision event.

McKenna (1972) also raised the possibility of driftin
Arks’) resulting in a one-way transfer of biota from one area, through rifting, to ano—
ther area on collision. Again, the collision effects would be gradual, with the Noah’s
Ark biota probably greatly modified even before collision occurred.

The implications of continental movements for the interpretation of fossil data are
obvious, since fossil assemblages can be moved considerable distances from their
place of formation. Additional geophysical processes which also make it necessary to
consider the location and conditions of deposition include linear transform faulting
and latitudinal tilting as a result of polar wandering. Lateral motion along the Alpine
Fault in New Zealand, for example, is estimated to be 1 200 km (Griffiths & Varne,
1972).

& continental blocks (‘Noah’s

The new biogeography of Australia

Age and origin of the angiosperms

The flowering plants are usually assumed to be monophyletic, largely because cer—
tain basic features such as double fertilisation and triploid endosperm are unique to
the group and constant within it. A corollary to this theory is that the angiosperms
have radiated from a single place of origin. However several authors have argued that
there are several archetypes of the angiosperms and consequently have concluded
that they are polyphyletic. For example Krassilov (1977) has suggested that three
major Cretaceous angiosperm stocks, viz., Hamamelidales, Laurales and monocoty—
ledons have been derived independently from three Mesozoic ‘proangiosperm’ seed
plant groups respectively, viz., Dirhopalostachyaceae, Caytoniales and Czekan—
owskiales. Other authors, such as Cronquist (1968), have expressed some uncertainty
and have described the various angiosperm features as ‘having evolved separately in
different lines’.

While the question of the origin of the angiosperms is still unresolved, there is no
doubt that they had achieved a wide distribution well before the rifting and separa—
tion of the supercontinents. Monosulcate pollen, which is characteristic of the mono—
cotyledons and of the Annonales and Nymphaeales among the dicotyledons, is
known from Barremian (Lower Cretaceous) beds in Europe and North and South
America (Raven & Axelrod, 1974). Tricolpate pollen, which is characteristic of all
other dicotyledons, is also known from beds of similar age at several widespread
localities, and an origin in western Gondwanaland has been suggested for this group

Origin and Evolution

by Brenner (1976) and strongly supported on several grounds by Raven and Axelrod
(1974). By mid-Cretaceous times angiosperms were widespread, their pollen had
become more abundant in the record than fern spores and gymnosperm pollen, and a
few modern families may have existed. By the end of the Cretaceous, numerous
modern families and even genera were definitely present. Thus many present-day
groups were present 90 m.y. BP when direct exchange between Africa and South
America was still possible. All but the most recently derived families existed when
direct migration between South America and Australia via Antarctica was still pos—
sible 45 m.y. BP (Raven & Axelrod, 1974). This interpretation bears out the conclu-
sions on southern hemisphere plant distribution reached much earlier by Camp (1947,
1952).

Current evidence suggests that the angiosperms did not originate in Australia but
reached the region by migration from other parts of Gondwanaland. The oldest
known Australian angiosperm pollen flora significantly post-dates that of northern
Gondwanaland and consists of monosulcate types of early Albian age (Dettmann,
1981). Tricolpate forms date from the middle Albian, and the sequential introduction
of pollen types is later in Australia than in northern and western Gondwanaland.
Dettmann (1981) has concluded that the introduction of angiosperms into Australia
was an Albian event, c. 120 m.y. BP, and was perhaps 5 million years later than the
inception of angiosperms in northern Gondwanaland and southern Laurasia.

The Gondwanan flora in Australia

The original angiosperm flora of Australia was presumably derived from immigra—
tion over broad fronts and probably already showed a wide range of ecological
adaptation. Raven and Axelrod (1974) have suggested that a subtropical migration
route from Africa to Australia via India may have persisted until middle-late Creta—
ceous times (Fig. 14), and that until the late Cretaceous there may still have been ex—
change between Australia and the rifting Madagascar and India. Even after this
migration route was broken a south temperate route to Australia from South America
via Antarctica remained, perhaps until the Oligocene (Raven, 1979). At this time
there were forests of Nothofagus and southern gymnosperms, Proteaceae and Myrt—
aceae to at least 77°S latitude in Antarctica (Kemp & Barrett, 1975; Thomson &
Burn, 1977).

A scenario is thus presented for an Australian flora at the beginning of the Ter—
tiary period, with Australia still broadly connected to Antarctica but well separated
from Africa, New Zealand and India. Climatic conditions were warm and moist; high
rainfall was general in southern Australia and extended through the interior. Tem-
peratures were high in northern and inland Australia (Wopfner et al., 1974) and
warm (20-25°C) in southern Australia. The vegetation was more or less uniform
structurally, with closed subtropical rainforest being more or less continuous. Some
ecological zonation probably existed, with limited differentiation in floristic composi—
tion between the warmer and more temperate habitats. This is probably the only
sense in which there has been a pan-Australian flora, a concept first proposed by
Diels (1906) and later accepted by several authors after it was developed by Crocker
and Wood (1947). The pan-Australian flora was Gondwanan rather than autoch—
thonous as visualised by many of these authors. The southern beech Nothofagus was
already widespread, as were plants referable to Araucaria, Podocarpus, Dacrydium,
Anacolosa (Olacaceae), Cupanieae, Myrtaceae, Nipa and several Proteaceae.

Critical studies of a number of plant groups have further strengthened the argu—
ment for an ancient Gondwanan element in the Australian flora. Not unexpectedly,
there is a strong Gondwanan character in certain Australian fern groups and in the

Origin and Evolution

gymnosperms (Page & Clifford, 1981). Ancient establishment in the Australian flora
has also been postulated for the Myrtaceae, Proteaceae and Restionaceae (Johnson &
Briggs, 1975, 1981), Loranthaceae (Barlow & Wiens, 1971; Barlow, 1981la), Rhodo-
dendron and Vaccinium (Specht, 1981c), and even for such an advanced and
specialised group as the Poaceae (Clifford & Simon, 1981). Raven and Axelrod
(1974) have listed many families in 15 orders, the ancestors of which may have
reached Australia in Cretaceous times by a subtropical route from Africa. These
include, among others, Goodeniaceae, Casuarinaceae, Epacridaceae and Pittos—
poraceae.

The Tertiary evolutionary history of the Australian flora has thus been one of dif-
ferentiation from the original Gondwanan stock. The process occurred under condi-—
tions of increasing geographical isolation from the time of Australia’s separation from
Antarctica in the early Tertiary until its contact with the Sunda plate in the Miocene.
It was in response to progressive climatic changes until, in the Miocene, conditions
were established which were comparable with those of the present. The climatic
changes, involving decreasing mean temperatures, increasing intensity of oceanic cir—
culation and of atmospheric circulation, regional decreasing precipitation and in-
creasing seasonality, would have resulted in an increase in the level of habitat differ—
entiation. The earlier pan-Australian flora would have thus undergone differentiation
into a spectrum of ecological associations.

60°N

Cretaceous
lod t1Omy. B.P.

Figure 14. Conformation of the southern continents at the time of establishment of
the Gondwanan flora in Australia. (From Raven & Axelrod, 1974; reprinted by
permission from Ann. Missouri Bot. Gard. 61: 541)

Origin and Evolution

The autochthonous element of the Australian flora thus emerges as the derived
one rather than the most ancient one. It simply comprises those components of the
flora which have undergone considerable evolutionary change, under conditions of
geographical isolation, to produce typically Australian taxa with high levels of
endemism. The so-called Indomalayan and Antarctic elements are now seen as com—
prising, at least in part, the present-day survivors of the Gondwanan flora which have
been conservative in the evolutionary sense.

The major floristic composition of the Australian vegetation was thus laid down
by the middle of the Tertiary period. It is Gondwanan in origin. It exists today as
two components with a relatively strong ecological differentiation. One is the relictual
component, consisting of taxa confined to moist habitats (usually closed forests),
showing little evolutionary diversification, and showing a residual taxonomic affinity
with the floras of similar habitats in the other southern lands. The other is the der—
ived Australian (autochthonous) component, predominantly temperate and arid-adap—
ted, showing massive evolutionary diversification from the more labile of the ancestral
Gondwanan stocks and characterised by scleromorphy and high endemism. Nelson
(1981) has termed this entire flora the Gondwanic element, and the two components
the relict and autochthonous sub-elements respectively.

The flora has been moulded and added to by later geophysical and climatic
events. Of major significance has been an apparent geographical isolation of the tem—
perate floras of eastern and western Australia. It may have been initiated by marine
incursions into southern Australia which were possibly continuous from late Eocene
to mid-Miocene times (Nelson, 1981). The emerged sediments have since remained
as dry land and form the limestones of the present Nullarbor Plain. Subsequent in-
creases in aridity (Crocker & Wood, 1947; Raven & Axelrod, 1974) may have main-—
tained an edaphic and climatic barrier between east and west to the present, with
little interruption (Nelson, 1981).

The isolation is reflected in the high level of specific endemism in the flora of the
south-west of Western Australia, estimated at 87 per cent by Beard (1969) and modi-—
fied to 68 per cent by Marchant (1973a) and to 75-80 per cent by Hopper (1979).
Generic endemism is low and there are many vicarious species pairs in eastern and
western Australia. This is consistent with the imposition of isolation at a time when
the major genera of the autochthonous sub-element were already widely established.

The extremely species-rich flora of the South West Botanical Province of Western
Australia, with its high specific endemism, is attributed to its long history of develop—
ment in geographical isolation, on a relatively stable land surface on which a mosaic
of soil types has evolved. There is little to support the view of some floristic analysts
that this richness indicates that the autochthonous flora originated in Western Aust—
ralia. It has been shown by Hopper (1979) that the greatest species density occurs in
the transitional rainfall zone between the mesic forest areas and the arid zone, and
that a high proportion of the species are very local endemics within this zone. He
concluded that in the more recent geological past conditions have been more
favourable for speciation in this zone than in the more mesic and more arid zones. In
particular, he has pointed out that recurrent climatic fluctuations would have
generated greater stresses in the transitional zone and, coupled with the evolution of
a mosaic of nutrient-deficient soils, would have produced disruptions in labile
population systems ideal for rapid speciation.

The corollary to species richness is that many species have very small geograph—
ical ranges because of their geographical replacement patterns. This is true of Aden-
anthos, Stylidium, Darwinia, Eucalyptus, Banksia and Acacia (Nelson, 1981). In
Stylidium, cross-compatibility between neighbouring populations of a species is often

Origin and Evolution

low (Farrell & James, 1979), indicating that selection for reproductive isolation b
tween neighbouring populations is very high. This phenomenon may be pueeeecy
with the maintenance of highly adaptive local biotypes under conditions of ee
competition on nutrient-deficient soils. Ble

As mentioned above, the karyoevolutionary data of Smith-White and others ¢
be reconciled easily with the current view of the history of the Gondwanan Bicientt
Their studies revealed recurring patterns of chromosome number variation in which
autochthonous groups showed greater diversity than non-endemic or extra-Australian
ones, with polploidy apparently superimposed as a tertiary phase on extensive secon—
dary dysploidy. In addition to the several groups cited above, subsequent studies have
revealed comparable patterns in a number of other groups, including Restionaceae
(Briggs, 1963), Papilionaceae (—Fabaceae) (Sands, 1975), Stackhousiaceae (Turner
1966), Droseraceae (Marchant, 1973b), Stylidium (James, 1979) and Hibbertin
(Stebbins & Hoogland, 1976). The dysploid changes can now be seen as devices
which have conserved adaptive biotypes during the differentiation of the autoch—
thonous sub-element; they have served to restrict gene pools, thus favouring diversifi—
cation, but have led to a new stability in the derived groups. This explains why
dysploidy is so characteristic of the generic rank or its equivalent. Further genetic
conservation of adaptive biotypes has very frequently involved polyploidy, both in
woody and herbaceous groups. As pointed out by James (1981), these changes
illustrate the ‘unceasing selection of conservative devices which ensure minimal
departures from already tested adapted parental genotypes’. It is noteworthy that
within this framework of genetic conservation a number of groups have evolved
mechanisms which maximise genetic heterozygosity.

The parallel karyological patterns thus illustrate the condition under which the
autochthonous sub-element has evolved—strong selection, under conditions of strong
competition, for the maintenance of highly adaptive new biotypes as they have arisen
under progressively changing environmental conditions. This pattern has been devel—
oped most strongly in the scleromorphic flora of nutrient-deficient soils, particularly
under developing temperate conditions.

An expression of uniqueness—scleromorphy

The most striking aspect of the autochthonous element is its scleromorphy. Many
of its major groups are characterised by relatively small, rigid leaves, by short inter—
nodes and by small plant size. There is a strong representation of such types in Aust—
ralian Myrtaceae, Proteaceae, Rutaceae, Epacridaceae, Mimosaceae, Fabaceae and
Goodeniaceae. It was generally assumed by earlier botanists that scleromorphy in the
Australian flora represented adaptive responses to an increase in aridity, and in par—
ticular to the advent of mediterranean climate. An exception was Andrews (1916),
who linked scleromorphy with soil properties and suggested that it was an adaptive
response to low levels of soil nitrogen and calcium. More recently several authors
have taken up the idea that scleromorphy is an adaptive response to nutrient defi—
ciency (Beadle, 1954, 1966, 1968, 1981; Johnson & Briggs, 1975, 1981; Loveless,
1961; Specht, 1972). Its expression is accepted as a response to chemical constraints
on growth and as a physiological process marked, among other things, by a reduction
in the number of cells formed. Beadle (1954, 1968) suggested that soil phosphorus
levels regulate soil nitrogen fixation and that phosphorus status is the basis of sclero—
morphy as a physiological adaptation.

Conditions favouring the evolution of scleromorphy in the Australian flora prob-
ably existed early in the Tertiary period. Specht (1981b) has pointed out that heath
communities are part of the moist tropical ecosystem, forming a mosaic with closed

~ 45

Origin and Evolution

forest communities and occurring on deep infertile sandy soils. They share families
and genera in common with rainforest. Beadle (1981) has suggested that sclero-
morphy began to differentiate at the margins of rainforest, proceeding along declining
soil fertility gradients. This view was shared by Johnson and Briggs (1981), who dis—
cussed the evolution of scleromorphy in relation to their analysis of relationships in
the Myrtaceae, Proteaceae and Restionaceae. They argued that the differentiation of
scleromorphic taxa began at least in early Tertiary times in nutrient-deficient forest
sites, possibly catalysed by climatic change, and that the process has continued
through successive differentiations as the climate has been progressively modified.
Because so much of the Australian land surface has undergone weathering contin-—
uously for a long time, poor soils are now the rule. Conditions favouring sclero—
morphic vegetation in Australia have therefore become progressively more wide—
spread, resulting in an expression of scleromorphy not matched in other continental
floras.

Scleromorphy may have been a pre-adaptation to mediterranean climate, so that
the scleromorphic flora may have colonised the habitats where this climatic regime
was established later in the Tertiary. The scleromorphic flora has, however, remained
confined to low-nutrient soils even under increasingly dry conditions, not effectively
spreading onto adjacent high-nutrient soils. Van Steenis (1979) has pointed out that
this feature of scleromorphic communities may explain the very limited represen—
tation of an Australian floristic element in Malesia (see below).

The post-Miocene intrusive element

Another major event in the history of the Australian flora was its late-Tertiary
contact with that of the Indomalayan region. The Miocene collision between the
Australian plate and the Sunda arc brought together two rich floras which, until then,
had been isolated from substantial direct exchange for a considerable period. The
geological history of the north-western margin of the Australian plate has been very
complex, however, and the way in which these two floras came in contact is not
clear. It was suggested by Audley-Charles et al. (1972) that Timor and several other
islands of the Outer Banda Arc, and even the eastern part of Sulawesi (Celebes),
formed part of the north-western margin of the Australian plate through the Meso-
zoic and much of the Cainozoic. A more general view, however, is that Timor formed
part of the margin of the Australian plate and that the other islands were part of the
Outer Sunda Arc (Grady & Berry, 1977; Powell et al., 1981). Timor may therefore
represent a limited exception to the suggestion by Raven (1979) that no part of Indo-
nesia was ever part of Gondwanaland. Southern New Guinea also formed part of the
Australian plate margin to the north (Fig. 15).

In Miocene time the leading edge of the Australian plate collided with the Sunda
Arcs, first involving the New Guinea margin of the plate, and later the margin further
west (Powell et al., 1981). At this time the Sundaland plate was moving westwards,
and as the Australian plate continued northwards the Sunda Arcs were contorted into
the great fold which now accounts for the position of islands such as Sulawesi and
Seram, north of the Inner Arc islands such as Sumbawa. These islands have probably
increased to their present size as a result of the collision effects. With the continued
westward rotation of the Sundaland plate since the collision occurred, the distance
between Australia and these lands has subsequently increased again. The chronology
of these events was interpreted similarly by Audley-Charles et al. (1972), but their
interpretation differs in that they postulated the collision and rotation of the Outer
and Inner Sunda Arcs as the margins of the Australian and Sundaland plates res—
pectively (Figs 15-17).

YNIHD-OON!
30 inanano”t

a Cee, ;
Ru % ‘ 25 \

- ~ ogre
WHARTON

BASIN

AUSTRALIA

\ NEW
| Yeon
‘ie?

ANTARCTICA

Figure 15. Reconstruction of part of Gondwanaland showing the position of New
Guinea and eastern Indonesia during the late Cretaceous. The present-day outlines
are shown for reference and have no palaeogeographical significance. The proposed
position of the volcanic island arc is related to the northward drift of
Australia-Antarctica initiated in the mid-Cretaceous. BOM = Bomberai; VOG =
Vogelkop; M = Misool; E.S. = East Arm and S.E.S. = South-east Arm of Eastern
Sulawesi; S.N.G. = South New Guinea province. (From Audley-Charles et al., 1972;
reprinted by permission from Nature Phys. Sci. 239: 35-39. © 1972 Macmillan
Journals Ltd.)

ES
&s

PP MY ®

INDIAN a) AMES
ghetto!
OCEAN | oa Seo

(‘earns OF MAUBISSE IS. | CoM

—

ACCRETED TO FRONTAL 2 aoe
ZONE OF ARC savy 20" bs a
WHARTON $3
BASIN / 2 —

AUSTRALIA

ANTARCTICA SEPARATING FROM ea 5
AUSTRALIA BY SPREADING FROM INDIAN-

“ANTARCTIC RIOGE (MCKENZIE & SCLATER.1971) ~) ?
wy MIDDLE MIOCENE

Figure 16. Reconstruction of Australia showing its relationship with Indonesia and
part of Melanesia during the Middle Miocene. The present-day outlines are shown for
reference and have no palaeogeographical significance. Note the opening of the Coral
and Tasman Sea basins and the anticlockwise rotation of Central New Guinea,
eastern Sulawesi, Buru and Seram. Northward-drifting Australia had separated from
Antarctica. B = Buru; H = Halmahera; M = Misool; BOM = Bomberai; S.N.G. =
South New Guinea province; S.E.S. = South-east Arm and E.S. = East Arm of
eastern Sulawesi. (From Audley-Charles et al., 1972; reprinted by permission from
Nature Phys. Sci. 239: 35-39. © 1972 Macmillan Journals Ltd.)

cy
SANGIHE IS ° f
5 iL PACIFIC

at N suawess 48
we /Y(E

BORNEO \4
on
a)

= iH OCEAN

SULA I's HALMAHERA

Meee

3 4s

SERA

an 0B!

/.
RUE 4S ot
Ss

i)
Pd
Oe

=
SUBDUCTION T E T H Y Ss KAI evi a

5m 28 Lranimear
INDIAN aes

AUSTRALIA

MIDDLE PLIOCENE

Figure 17. Reconstruction of northern Australian margin, New Guinea and eastern
Indonesia during the middle Pliocene. Note progressive development of the island arc
systems related to the northward drift of Australia. The present-day outlines are
shown for reference and have no palaeogeographical significance. BOM = Bomberai;
VOG = Vogelkop; N.N.G. = North New Guinea province; C.N.G. = Central New
Guinea province; S.N.G. = South New Guinea province; S.E.S. = South-east Arm
of eastern Sulawesi; W.S. = Western Sulawesi; S.F.Z. = Sarasina fault zone; Sorong
F.Z. = Sorong fault zone. (From Audley-Charles et al., 1972; reprinted by permission
from Nature Phys. Sci. 239: 35-39. © 1972 Macmillan Journals Ltd.)

Origin and Evolution

There are various interpretations of the formation of the present island of New
Guinea. Audley-Charles et al. (1972) postulated a rotational movement which
brought component blocks together on the northern margin of the Australian plate
(Figs 16, 17). Simpler explanations involve northern New Guinea being an island arc
beached and uplifted against southern New Guinea as the Australian plate moved
north (Raven, 1979), or northern and southern New Guinea having been contin—
uously in close proximity and eventually united by the uplift of a trough between
them (Crook, 1981).

The present Indonesian Archipelago and the Papuasian region are therefore deri—
ved from a complex interaction between parts of the Australian plate and the Pacific
and Sunda arc systems. Floristic exchanges as a result of this contact have occurred
in both directions, resulting in a limited integration of the Gondwanan and Laurasian
floras in the Malesian and western Pacific regions. Because such a diversity of primi—
tive relictual angiosperms occurs in the area today, some authors have suggested it as
the site of origin of the angiosperms (Takhtajan, 1969; van Steenis, 1971). The turbu—
lent geological history of the area, and our present knowledge of the sources of its
flora, make this idea clearly untenable (Schuster, 1976).

The so-called Australian element in the Sundaland region is highlighted by a few
species in genera such as Casuarina, Araucaria, Banksia, Grevillea, Acacia and
Eucalyptus (van Steenis, 1936). This element has been over-emphasised because of
the distinctive nature of the species involved (van Steenis, 1950) and by the erron—
eous inclusion of genera such as Casuarina which have had a much longer history in
the region. Nevertheless a number of Australian taxa have penetrated into Sundaland,
including Ptilotus (Stewart & Barlow, 1976a), Sty/idium (Erickson, 1958) and several
grasses (Clifford & Simon, 1981). Van Steenis (1979) has listed 98 ‘eastern or south-
eastern’ species, with a variety of lifeforms, in the flora of the Lesser Sunda Islands,
and of these 65 also occur in Australia, many of them in genera which are well
developed in Australia. In the Loranthaceae the Amyema group of genera, with x =9
and large chromosomes, is Papuasian in origin but has spread and diversified in the
Philippine and Sunda regions.

Few of the Australian taxa which have penetrated Sundaland have extended
beyond it into south-east Asia or beyond (Specht, 1981c), presumably owing to the
richness and stability of the Laurasian flora, and to the general lack of nutrient-defic—
ient soils, to which much of the Australian flora is adapted (van Steenis, 1979). A
few Australian grass genera have reached south-east Asia (Clifford & Simon, 1981).
In Dodonaea, which has apparently had a long history in tropical and temperate
Australia, one pioneering species complex has dispersed widely through south-east
Asia and Africa, as well as to the New World (West, 1980); its lack of diversification
indicates that this range extension is relatively recent.

Migration in the reverse direction has been more significant. New Guinea has
been colonised predominantly from the Malaysian region following its elevation above
sea level at the end of the Oligocene (Raven & Axelrod, 1972). Secondary exchanges
from New Guinea, and direct immigration from Sundaland, have contributed a sig—
nificant component of the Australian flora, especially in tropical ecosystems. This is
reflected in the low frequency of endemic genera in Australia’s tropical zone (14
per cent, Burbidge, 1960), compared with that of the temperate zone (46.6 per cent).
Burbidge (1960) noted that a high proportion of the non-endemic Indomalayan
genera in the tropical zone have only one or few species in Australia. This can be
explained as a result of relatively recent immigration into a floristically rich region in
which diversification has been restricted by stabilising selection. Burbidge’s analysis
showed that in the tropical zone there are 360 non-endemic genera represented by a

Origin and Evolution

single species in Australia and 320 genera represented by 2-5 species. It should be
borne in mind, however, that the same data could support the existence of a Gond-
wanan component in the tropical flora, and the significance of such a component in
the tropical flora should not be overlooked when Burbidge’s data are considered.

In Loranthaceae, two groups of genera appear to have entered the Australian-
Papuasion region as a result of the contact with the Indomalayan flora. The Decais—
nina group of genera, with x=12 and large chromosomes, is an excellent example of
an Indomalayan stock in which one or a few species of several genera have reached
the region (Barlow, 1981a). Only one genus, Lysiana, has originated in the Australian
region and undergone a limited radiation into the temperate and arid zones.
Dendrophthoe, with x=9 and small chromosomes, is centred in South-east Asia and
is represented by one widespread species extending from India to south-eastern
Australia and by a few young endemics in New Guinea and northern and eastern
Australia.

The late Tertiary elevation of mountain systems between Malaya and New
Guinea has probably provided a dispersal route for cool temperate plants, and this
dispersal route may have extended through eastern Australia. Long-distance dispersal
between isolated highland regions has almost certainly been involved, as the Indomal—
ayan lowlands have possibly remained continuously warm and humid (van Steenis,
1934a,b, 1936). A number of typically north-temperate genera may have been
dispersed to the Australian region by this route and some have apparently undergone
new radiations, especially in the New Guinean highlands (Raven & Axelrod, 1972).
Genera in Australia which may have had this history include Veronica, Euphrasia,
Poa, Stellaria, Ranunculus, Ajuga, Viola and some Apiaceae (Burbidge, 1960; Raven
& Axelrod, 1972).

Because of the complex floristic history of the southern Asian region, the late
Tertiary immigrant flora in Australia may have had diverse origins. In particular, the
role of the Gondwanan flora of India may be relevant. The Indian plate rafted from
Gondwanaland about 125.m.y. BP and collided with Asia in the middle Eocene, at
least 50 m.y. BP (Raven & Axelrod, 1974; Powell et al., 1981). The crustal shorten—
ing and elevation of the Himalayas followed later, reaching a peak at the end of the
Tertiary period although India is still moving northwards at 5 cm per year. Specht
(1958, 1981c) has drawn attention to the strong relationship between the floras of
sandstone habitats in monsoonal India and northern Australia, and suggested that
these are vicarious remnants of the Gondwanan flora. Other floristic alliances, how-—
ever, were eliminated as India moved through a succession of climatic regimes on its
northward drift (Schuster, 1976). These could have included tropical and temperate
southern stocks (Raven & Axelrod, 1974) and heathland flora (Specht, 1981c). India
thus carried a reduced flora when it reached Asia, but some of its taxa have spread
more widely in Asia (Raven & Axelrod, 1974; Specht, 1981c). Subsequently, with the
opening of a direct migration route to Australia, some derivatives of this ancient
Gondwanan stock may have re-entered Australia.

The Loranthaceae again provide a likely example of this sequence. While the
family is undoubtedly Gondwanan, two generic alliances appear to have had a long
history in Asia and one of them secondarily in Africa. These are the Decaisnina
group of genera and the Dendrophthoe group, described above. It seems plausible
that the ancestors of both groups reached Laurasia via India in early Tertiary times
and underwent extensive secondary radiations there. The former group now com-—
prises more than 100 species in South-east Asia and Indomalaya, while the latter is
represented by about 100 species in Asia, the Middle East and southern Europe and
by the entire loranthacean flora of Africa (about 300 spp.). As mentioned above, both

Origin and Evolution

of these generic alliances have attained a limited representation in Australia as re—
colonisers since the Miocene.

The floristic implications for Australia of these events have been well summarised
by Nelson (1981). In addition to the Gondwanic element defined above, he has also
defined an ‘Intrusive element’ comprising plants which have entered Australia sub-—
sequent to its separation from Gondwanaland. Within this element he has recognised
three sub-elements, namely (1) a tropical sub-element consisting of taxa of recent
derivation from tropical South-east Asia, (2) a cosmopolitan sub-element of widely
distributed genera and species, widespread in Australia especially in arid areas, and
(3) a neoaustral sub-element of mainly temperate species derived by recent migration
from the northern hemisphere. If the first of these sub-elements is to be viewed as
strictly Laurasian, then perhaps we could add (4) an Indogondwanan sub-element,
consisting of plants of ancient Gondwanan derivation which have reached Australia
as part of the Intrusive element.

The integration of the Australian flora

The Australian flora thus emerges as an amalgum of taxa with diverse histories
and potentials. It includes taxa the ancestors of which have been in Australia since
the dawn of the age of flowering plants, and it includes a variety of recent colonisers,
which in some cases have just established a foothold in Australia and in other cases
have diversified at the expense of previous inhabitants. It includes taxa which are
evolutionarily conservative, so that their relationships and origins are clearly evident,
and it includes taxa which are evolutionarily labile, having diversified and adapted to
occupy the spectrum of niches which have arisen through time. The changes which
have occurred in the latter group have yielded a distinctive array of genera that are
endemic to the region and unique in many aspects of their structure and function.
From an integration of palaeobotanical, palaeoclimatic and geophysical evidence, the
historical relationships of these components of the flora have now become clear.

While each of the elements and sub-elements of the flora tends to dominate in a
particular ecological situation, there is nevertheless a significant integration of these
floristic units within each major plant formation in Australia. Specht (1981a,b) distin—
guished 32 plant formations in Australia, and analysed the distributions of 1 285
genera represented in them. He concluded that almost every one of these formations
contains a mixture of genera which belong to different floristic groups in terms of
geographical distribution and relationships. That is, the modern Australian flora is
differentiated into major plant formations which nearly always include representatives
of several of the historical elements and sub-elements of the flora.

The integration of the floristic elements and sub-elements in the flora is illustrated
by their growth and flowering rhythms. The flora can be divided into three broad
thermal response groups (Nix, 1981; Specht, 1981b), based on the temperatures at
which seasonal shoot growth is initiated. These growth rhythms correlate reasonably
well with the accepted components of the flora, indicating that they have been
retained through a considerable time and climatic sequence. The potential growing
seasons of the three groups are within the temperature ranges of (1) > 25°C, (2)
15-25°C, and (3) 10-15°C respectively. Particular plant associations may include more
than one of these thermal groups and some members of an association may thus be
out of phase with the current climate of the region. Increasing seasonality of the cli-
mate has probably had a major role in the fluctuating interactions of these functional
components of the flora, perhaps outweighing the effects of aridity per se (Nix,
1981).

Origin and Evolution

Three thermal response groups in the herbaceous flora can also be distinguished in
another way (Specht, 1981a,b). These are temperate C, plants, tropical C, plants and
tropical C, plants, each with a distinctive response of biomass increment to mean
daily temperature. Grasses with the C, dicarboxylic acid metabolism are perhaps
more efficient photosynthetically than C, plants and are widespread in most open
plant communities in Australia. Among the chenopods, C, species of genera such as
Atriplex and Maireana are likewise dominant in arid situations (Parr-Smith, 1981;
Specht, 1981b). The C, understorey plants have thus had an important role in the
differentiation of plant communities in Australia. It is only in closed forests, wet
freshwater swamps and montane habitats that C, herbs are replaced by those of the
C, groups. In southern Australia, however, the native C, grasses, with a high, out-of-
phase temperature threshold for shoot growth, are being replaced by introduced tem—
perate C, grasses which are phenologically better adapted, attaining maximum shoot
growth at lower temperatures much earlier in the spring.

The climatic events of the more recent past which have influenced the develop-—
ment of the Australian flora after its general character was established have been well
documented. An excellent review by Galloway and Kemp (1981) summarises the ef-
fects of continental displacement, volcanism, temperature and sea level fluctuations,
and their expression in terms of dune formation, vegetation shifts and speciation.
Some aspects of this phase of vegetation history are discussed below in relation to the
evolution of an arid zone flora, but there are some important general considerations
which arise from the data.

In the Quaternary, climatic changes were generally more rapid and extreme than
were general in the Tertiary and they have certainly affected Australian biogeography
profoundly. This period represents only a small fraction of the time interval in which
the Australian flora has developed, however, and the fluctuations appear to have been
within the ecological tolerances already well established in the flora. Major vegeta—
tional changes indicated by pollen analysis may have been only local migrations of
adjoining vegetation types. The record indicates, for example, that tropical rainforest
returned to north-east Queensland only about 10 000 years ago after an absence of
70 000 years (Galloway & Kemp, 1981), but it may have been present not far away
from the sites examined. Even today there are very steep environmental gradients in
the region, with different vegetation types occurring only short distances apart.

This situation has probably existed at least since the early Pliocene. Pollen records
suggest a transition from older rainforests, dominated by Nothofagus and southern
gymnosperms, to open forest dominated by Eucalyptus, Casuarina, grasses and com-—
posites. Nonetheless records of wet forest plants at some sites throughout the epoch
again suggest that the vegetation was a shifting mosaic of communities similar to
those of the present. :

A similar explanation for the history of alpine plants in Australia may be neces—
sary. High mountains have been continuously absent through the Cainozoic (Gal-
loway & Kemp, 1981) and alpine habitats have probably always been limited. They
may have been repeatedly eliminated during thermal maxima, and alpine plants may
have survived in refugial habitats such as stream banks. The rather disharmonic alpine
flora may represent only the surviving remnants of earlier alpine communities.

Origin and Evolution
Torres Strait and Bass Strait — land bridges of the recent past?

New Guinea — a floristic crossroads

A broad spectrum of views on the relationship of the Australian flora with that of
New Guinea has been expressed, but there has been a progressive change of view as
the palaeogeography and palaeoclimate of the Torres Strait region have become better
understood. Van Steenis (1950) argued that Torres Strait was one of the principal
floristic ‘demarcation knots’ of the Old World Tropics. He defined a demarcation
knot in terms of the total number of genera which reached their distribution limits in
the area concerned. For Torres Strait the demarcation knot was 984, comprising 644
Malesian and endemic genera in New Guinea which were absent from Australia and
340 Australian genera absent from New Guinea. Van Steenis used this concept to
argue that New Guinea was part of the Malesian floristic region. The sharpness of the
floristic transition across Torres Strait was also emphasised by Good (1960) who
stated that of 1 350 indigenous genera in New Guinea, only 62 are Australian (in the
sense that the bulk of the species are found in Australia).

While the predominant view of the time was that the New Guinean and Aust—
ralian floras are quite distinct, not all authors viewed Torres Strait as the boundary
between the two. Because of the physiognomic and floristic resemblance of the open
savannahs of western Papua and Cape York Peninsula, several authors treated south-
western Papua as part of the Australian floristic region (Good, 1963). On the other
hand Herbert (1935, 1960) suggested that the rainforest of north-eastern Australia
should be included in the Malesian floristic region.

On the basis of current views of late Tertiary and Quaternary palaeogeography
the Torres Strait region is now seen as more of an ecological boundary than a geo—
graphical one. Following the regression of the sea in the early Tertiary, the northern
margin of the Australian plate (including southern New Guinea) remained as dry land
(Doutch, 1972). Thus when New Guinea began to assume its present form and rela—
tionship with Australia, there was no seaway between the two regions, and by Plio-
cene times most of New Guinea had emerged and formed the northern part of the
Australian land mass. The seaway formed by the Arafura Sea and Torres Strait prob-
ably only came into existence in the Pleistocene and it has almost certainly been re-
established as a land link at least seven times through subsequent sea level fluctua—
tions (Doutch, 1972; Galloway & Loffler, 1972; Galloway & Kemp, 1981). Torres
Strait was most recently formed between 6 500 and 8 000 years ago, and except for a
few channels is presently less than 10 metres deep (Jennings, 1972).

The relationship between the Australian and New Guinean floras must therefore
be determined on the basis of climatic history. During the last glacial maximum the
exposed Torres land bridge and the north of Australia would have been at least as
arid as the Carpentaria region is today (Webster & Streten, 1972). Nix and Kalma
(1972) have extrapolated from palaeoclimatic data to vegetation types through Quat—
ernary time and have described a pattern of north-south shifts in arid and open
woodland vegetation (Figs 18-21). They have pointed out that even if the hypothesis
for their calculations is incorrect, there is no doubt that a core area of closed rain—
forest has persisted in New Guinea and a core area of arid and semi-arid land has
remained in Australia.

Torres Strait may thus represent not so much a physical barrier to plant migration
as a zone of strong ecological differentiation between the regions cn either side of it.
Most of the species which occur on both sides of the Strait grow in coastal lowlands
and have presumably had access to suitable habitats for migration (Hoogland, 1972).
On the other hand there are very few rainforest species common to both sides of the

Origin and Evolution

Strait; sclerophyllous species occupy an intermediate position (Webb & Tracy, 1972).
This situation is consistent with the time periods during which their respective habi-—
tats have been isolated from exchange. In the main, then, the differences between the
Australian and New Guinean floras are probably the result of the long climatic sifting
of a single ancestral stock (Wace, 1972). Superimposed on this is the floristic effect of
the Indomalayan element (i.e. the tropical sub-element of the Intrusive element in the
Australian flora), which has become a major component of the New Guinean flora
but which for purely climatic and edaphic reasons has not achieved the same domin—
ance in the flora of northern Australia.

Tasmania — a living piece of Gondwana

The floristic history of Tasmania has been integrally bound with that of the rest of
Australia. Tasmania was still part of the Australian mainland at least until the Oligo—
cene or Miocene, when Bass Strait was first formed (Gill, 1962; Galloway & Kemp,
1981). The later Tertiary history is uncertain but it has been the tule, rather than the
exception, for Tasmania, mainland Australia and New Guinea to form one land mass
during the last million years. Bass Strait has been opened as a seaway at least eight
times, the most recent being 13 500-12 000 years BP (Galloway & Kemp, 1981). The
common floristic history is reflected by the analysis made by Burbidge (1960), which
showed that there are no families of seed plants endemic in Tasmania. About 100
families occur in Tasmania out of about 215 in the whole of Australia. Only 28 of
approximately 400 genera (7 per cent) and about 246 of 1 200 species (20 per cent)
are endemic. There is therefore a high level of similarity, even at the present day,
between the floras of Tasmania and the south-eastern mainland.

Because of its geographical position, its insularity and its relatively mountainous
topography, Tasmania has continuously retained an environment similar to that which
was widespread in Australia in early Tertiary times, and perhaps in Gondwanaland
prior to its fragmentation (Nelson, 1981). Its flora is characterised by Gondwanan
taxa such as Gunnera, Caltha, Coprosma, Orites, Lomatia and Nothofagus. The
alpine flora of Tasmania, particularly, reflects the long climatic stability, and many of
the endemic genera and species are found there. It also includes (in common with the
Australian Alps) many genera, such as Ranunculus, Epilobium, Euphrasia, Veronica,
Mentha and Carex, which have northern hemisphere affinities (Nelson, 1981) and
which have undergone their only southern radiations in alpine habitats. As suggested
above, these genera have reached Tasmania from the north along mountain migration
routes, in some cases aided by long-distance dispersal.

Endemism is much lower in the autochthonous component of the Tasmanian
flora. During the Quaternary there has been a broad, low, land connection between
Tasmania and the mainland at the times of glacial maxima and sea level minima. This
has allowed exchange between the lowland floras of the two regions.

The absence from Tasmania of so many families which occur elsewhere in south-
eastern Australia is probably due mainly to the small area of the island and its limited
habitat diversity; most of the families now absent probably never occurred there.
Some mainland groups, however, may have been eliminated from Tasmania during
the climatic fluctuations of the Pleistocene and may not have successfully recolon—
ised. Mistletoes (and mistletoe birds) are absent from Tasmania, probably having been
eliminated by cold conditions during glacial times and subsequently prevented from
returning by the Bass Strait sea barrier (Barlow, 1981a).

sti

ae a
ive ty
< i

i inl is

Figure 18 (above). Main structural vegetation types which might have occupied
northern Australia, New Guinea and the intervening land about 20 000 years BP. See

opposite for legend.

Figure 19 (below). Main structural vegetation types which might have occupied
northern Australia, New Guinea and the intervening land about 17 000 to 14 000
years BP. See opposite for legend.

ips
a

Shrubland

—-)- ~And veg

ore | sy Woodlng/ ;
WA - s \~ open forest |
a Low open woodland S. -Lthece temperate) *
io . ~ Nae ad +,
Pm ee Re Woodlans RCE (tropical)
——--- ne ment oe
ria Shrubland « 4 A
-- . ~ a
ce le peat Sh. vont}
ay Sp ne : =
Leite Ts or LIT ce 202
i Toe a And vegetation P< . \ ili
a e ° hs . \ Le £7
-- 124° 130 136 PSL ha20 Vt Lor

Figure 20 (above). Main structural vegetation types which might have occupied

northern Australia, New Guinea and the intervening land about 8 000 years BP.

Figure 21 (below). Main structural vegetation types which occupy northern Australia
and New Guinea at present.
Zenithal Equidistant Minimum Error Projection.

sranine Tropical/temperate junction ---------- Vegetation zone boundary
Estimated coastline = erveaeteeeeee Modern coastline
Closed forest. ° Observation station

(After Nix & Kalma, 1972; reprinted by permission from Bridge and Barrier 88, 89.
© Australian National University)

Origin and Evolution

The dominant Australians — Eucalyptus and Acacia

Two genera, Eucalyptus and Acacia, dominate much of Australia’s vegetation and
contribute greatly to its general character. The history of the Australian flora is in
large measure the history of these two genera.

Eucalyptus is not the largest Australian plant genus but it is certainly the most
significant, both economically and biologically. The number of species is currently
estimated at approximately 500 (Pryor & Johnson, 1981), almost all of which are
endemic to Australia. Six Australian species extend to southern New Guinea and a
seventh is endemic there. Only three species extend beyond Australia and the New
Guinean mainland. One, EF. alba, is widespread in northern Australia and southern
New Guinea and extends to the Lesser Sunda Islands. The other two, £. urophylla
and £. deglupta, are endemic to the Lesser Sunda Islands and New Britain-New
Guinea-Sulawesi-Mindanao respectively. It is noteworthy that the total natural distri—
bution of the genus Eucalyptus coincides approximately with the total extent of the
Australian plate in late Tertiary times as suggested by Audley-Charles et al. (1972).

For phytogeographical reasons alone there can be little doubt that Eucalyptus is
of ancient Australian origin, although the genus does not appear definitely in the fos—
sil record until the Oligocene (Gill, 1975; Martin, 1981). The eucalypts are not par—
ticularly closely related to the scleromorphic shrubby Australian Myrtaceae, nor to
arborescent groups such as Metrosideros (Pryor & Johnson, 1981), although they
apparently share a common ancestry. Detailed studies indicate that the eucalypts may
be a diverse group, with the floral operculum having been derived independently in
several ways and with significant variations in ovule and seed anatomy as well as in
inflorescence structure (Pryor, 1976; Pryor & Johnson, 1981). Because of other uni-
fying factors such as the presence of regularly arranged sterile ovules, it is thought
that the eucalypts may have had multiple origins from ancestral stocks which were
closely related. This theory has important taxonomic implications, since it may be
appropriate to reclassify the eucalypts into several distinct genera. Johnson (1976) has
recognised nine such ‘informal subgenera’ in Eucalyptus s. Jat., and Johnson and
Briggs (1981) have argued that these groups deserve generic status. Such an approach
is strongly supported by the distinct levels of crossability within and between these
groups. For largely practical reasons outlined by Pryor (1976) and Johnson (1976),
formal taxonomic delimitation of segregate genera has not been completed.

Eucalypts characteristically occur in open forest and woodland associations, and
only a few species have been successful in rainforest margins or alpine habitats. In the
arid zone they are relatively few and with rare exceptions confined to favourable sit—
uations such as stream lines and rocky outcrops. The genus is therefore often associ—
ated with the evolution of the scleromorphic autochthonous sub-element of the flora.
Pryor and Johnson (1981), however, considered that Eucalyptus did not move into
older scleromorphic communities until mid-Tertiary time.

The long history of the eucalypts is illustrated by a number of relict species of
very limited distribution, and by a striking evolutionary convergence between species
of different sections in eastern and western Australia, both in field appearance and in
ecological requirements (Pryor, 1976; Pryor & Johnson, 1981). Eucalypts also illust—
rate the long history of evolution of the Australian scleromorphic flora with fire; the
growth habit of these plants makes a major contribution to the flammability of the
vegetation. Eucalypts characteristically have narrow pendulous leaves which allow
light to penetrate to ground level, drying the copious leaf and bark litter which
accumulates. Depending on weather conditions, fires may be confined to the under—
storey layer or may rage through the crowns intensified by the volatile oils in the
leaves. Adaptations in eucalypts include woody capsules which release seeds after

Origin and Evolution

fire, thick insulating bark, numerous buds which allow sprouting of large limbs even
after intense scorching and, in most species, large woody rootstocks (lignotubers)
which are very resistant to aridity as well as to fire. Some of these attributes are
common to other genera of the Australian scleromorphic and arid vegetation. It has
been suggested that the flammability of the vegetation is an adaptation which pro—
motes rapid heat generation and rapid return to normal temperature, thus preventing
destruction of dormant buds (Recher & Christensen, 1981).

Much of the Australian flora may have been pre-adapted to fire by virtue of its
adaptations for aridity and nutrient deficiency (Specht, 1981b). Two adaptive strate—
gies are evident; some species are fire tolerant, with the array of protective features
mentioned above, while others are fire sensitive but produce large quantities of seed
which accumulate either in the soil or in woody fruit and germinate after fire (Recher
& Christensen, 1981). Eucalyptus and certain other genera (e.g. Banksia) have
species which fall into each class (Gill, 1975; George, 1976). Long-term successional
cycles in scleromorphic communities occur in response to fire (Recher & Christensen,
1981; Specht et al., 1958), with certain species in some cases reappearing in the com—
munity as a direct consequence of burning. Some eucalypts will not regenerate in the
absence of fire, which may therefore play an important role in maintaining the struc—
ture of eucalypt communities in Australia.

The other enormously successful genus in Australia is Acacia, which with c. 835
species (Maslin & Hopper, 1981) is the largest in Australia. Acacia is well represen—
ted in the floras of Africa and tropical America but one characteristic section, Phyl-—
lodinae, dominates the Australian representation. In this section the leaves, which, in
Acacia, are primitively bipinnately compound, are reduced in the adult state to
expanded petioles, often vertically flattened. This scleromorphic feature is usually
explained as an adaptation for aridity.

Acacia is known in the fossil record only since the beginning of the Miocene
(Martin, 1981), but it undoubtedly has had a longer Tertiary history in Australia.
Acacia species occur in nearly all plant formations, including closed forests, but they
tise to community dominance in the woody floras of arid and semi-arid regions. In
these situations Acacia tends to replace Eucalyptus as the dominant woodland genus
of open habitats, with Eucalyptus confined to more favourable sites.

While Acacia is ecologically dominant in the arid zone, only 118 of the 835
species (14 per cent) occur there, and endemism to that region is low (Maslin &
Hopper, 1981). In comparison, 336 species (40 per cent) occur in the South West
Botanical Province of Western Australia, indicating a remarkable diversification
within the scleromorphic ecosystems with mediterranean climate.

Acacia probably first radiated in Australia under the warm moist conditions of
the middle Tertiary, with some sections later evolving rapidly in southern areas in
response to aridity (Maslin & Hopper, 1981). At the present time the tropically de—
rived groups in the arid zone are phenologically in phase with environmental condi—
tions while the groups with southern connections are out of phase (Maconochie,

1979), and appear to be later arrivals. Ly

Origin of the Australian arid zone flora

The arid zone and the derivation of its flora

The arid or eremean zone in Australia is generally defined in terms of the
250 mm (10 in.) isohyet. Thus defined, it comprises more than one third of the Aust—
ralian land area. In addition, there are other floristic regions in Australia where sea—
sonal aridity is significant. In monsoonal northern Australia, for example, there is a

Origin and Evolution

prolonged winter dry season of up to nine months. Burbidge (1960) recognised three
large ‘interzones’ between the Eremean Zone and the other two floristic Zones, Tem—
perate and Tropical. The interzones were characterised by seasonal aridity, and in
some cases by heavy soils, and showed a significant representation of arid-adapted
plants. In the broad sense, then, more than half of the land area of Australia at the
present time is continuously or seasonally arid.

As a consequence, the relationships and evolution of the Australian arid zone
flora have received considerable attention. The first studies were purely phytogeo—
graphical and generally formed part of the more extensive analyses described earlier.
Tate (1888) coined the term ‘Eremia’, and distinguished two components, Endemic
and Exotic, in its flora. Diels (1906) redefined the arid zone under its current spelling
‘Eremea’ and recognised a Northern Element and an Autochthonous Element in its
flora; these correspond to the Exotic and Endemic Elements of Tate. The first of
these groups has palaeotropical relationships while the second is purely Australian.

Diels (1906), in what might have been a separate exercise, also classified the flora
of the ‘Eremean Province’ into components based on possible geographical deriva—
tions. These included a palaeotropical and cosmopolitan group, mainly in the north,
and an Australian group and a littoral group, mainly in the south. Diels also showed
an awareness of the overlap between temperate and arid floras in the south-west of
the continent. His phytogeographical classification of the arid zone flora seems to
have been taken up by Burbidge (1960) with little change. In her analysis she re—
corded 363 genera of seed plants in the eremean flora, of which 102 were endemic.
Of the remainder, 91 genera were also represented in temperate Australia and 81
genera in the adjacent lowland tropics. The cosmopolitan element was represented by
89 genera which were further distributed throughout all regions of Australia.

In terms of phytogeographical analyses, then, there has been little controversy in
explaining the derivation of the Australian arid zone flora. Most authors have conclu-
ded that it is a young flora, having arisen only after extensive arid conditions were
established in relatively recent geological time. It was therefore derived by selection
from the pre-existing, highly adapted, total Australian flora. Components of tropical
lowland affinity and derivation dominate in the northern part of the Eremea (Bur—
bidge, 1960) and components apparently derived from the autochthonous temperate
element dominate in the southern part. The main difficulty has been in the explan—
ation of the cosmopolitan component, including endemic genera in families such as
Poaceae, Chenopodiaceae, Brassicaceae, Aizoaceae and Asteraceae, which are among
the main constituents of the vegetation of all of the major world deserts. How did
these colonisers cross extensive areas of unsuitable and fully occupied territory to
become established in the young Australian arid zone?

The solution to the problem has generally been found in the fact that these cos—
mopolitan families and genera are also well represented in littoral habitats, where
salinity and soil type may impose physiological conditions similar to those of deserts.
Colonisation of the deserts by such groups may therefore have occurred from coastal
habitats, especially in places where the arid zone extends to the coast. Burbidge
(1960) placed great emphasis on this hypothesis and suggested that the progenitors of
the Australian arid zone vegetation existed on the coastlines from Cretaceous times
until the late Tertiary, when the first extensive arid areas were formed.

Age and climatic history

The arid flora is thus widely accepted as being a composite flora derived from ad—
jacent, older plant communities as arid conditions overtook the continent. The major
debates have centred on matters of detail. How recent is the arid zone flora? What

Origin and Evolution

types of genetic systems have operated in the selection of new biotypes from com—
munities which were already highly adapted? Is there any evidence that the arid zone
itself has been a major centre of species radiation. for those genera which have colon—
ised it?

Partial answers to these questions have emerged from a number of detailed stud—
ies, many of them very recent. The work which set the stage for many of these stud—
ies, however, was the celebrated paper by Crocker and Wood (1947). These authors
argued that the eremean flora was ultimately derived from a pan-Australian Oligo—
cene flora which existed under conditions of continental low relief, broad climatic
zones and high rainfall. From a study of dune formation they postulated cycles of
aridity alternating with pluvial phases. During the arid maxima there would have been
‘wholesale destruction of native flora’ coincident with both the formation of dunes
and sand sheets and the retreat of the vegetation cover into refuges, probably in the
inland mountain systems. As the climate again became more equable an arid zone
vegetation was re-established by migration from the refuges, but only by the adapt—
ively superior biotypes which remained. Migration routes would have been deter—
mined by soil type.

Crocker and Wood suggested that there might have been more than one such arid
maximum in Recent (post-glacial) times. However they suggested that the last arid
maximum, which they put at 10 000 years BP, was the major determinant of the
present arid zone flora.

As a result of Crocker and Wood’s work it was generally accepted that the arid
zone flora of Australia was very recent in origin, having differentiated mainly through
the sifting effects of cycles or aridity over the last 50 000 years. Other authors, not—
ably Burbidge (1960), argued from the available fossil and climatological evidence
that limited arid conditions may have arisen in the Pliocence (i.e. in the last few mil-
lion years), but that the extensive occurrence of arid conditions was post-glacial in
origin. This conclusion has only been questioned very recently. It should be noted,
however, that Crocker and Wood did postulate the existence of an earlier arid flora
before their ‘Great Arid Period’. Crocker (1957) later suggested that there probably
always was an arid zone in Australia, but that its size and position may have
changed.

The theory of plate tectonics has provided a simple means of estimating the age
of the Australian arid zone. If a steady northward drift of Australia from Antarctica
is assumed, then Australia would have entered the subtropical arid belt in Miocene
time. On this simplistic basis, the age of extensive aridity in Australia would be at
least 15 million years, and it would have impinged on the Australian continent from
the north (Beard, 1976).

Bowler (1981) has accepted the view that the present expression of aridity in the
Australian landscape dates from events which began in Miocene time. He has, how-
ever, questioned the concept that aridity was initiated from the north by Australia’s
drift into dry subtropical latitudes. He has suggested, from palaeoclimatological evi-
dence, that there has been a northerly displacement of weak sub-tropical anti- -cyclonic
pressure systems from winter latitudes near 50°S in the Miocene, with the present
climatic pattern over Australia being initiated about 2.5 m.y. BP and subsequently
intensifying. As a result, aridity would have overtaken the Australian continent from
the south rather than the north, and equable, moist, summer rainfall conditions would
have given way to seasonally dry conditons. With the continued northward
movement of the pressure systems the moisture budget would then have increased
again in southern Australia in the last 2.5 million years, leaving the interior with the
reduced moisture budget. According to Bowler the present arid zone landforms have

Origin and Evolution

a time-frame of 700 000 years but the major wet-dry oscillations of the last 100 000
years have been most significant in determining the landscape.

Recently available palaeobotanical data do indeed suggest that open and perhaps
arid plant communities have existed in Australia since the Miocene, whereas in the
preceding epochs moist conditions may have prevailed. As described above, the
pollen record for many widespread Eocene sites in Australia is consistent with the
presence of rainforest types such as Nothofagus, Podocarpus, Araucariaceae, Cupan—
ieae, Anacolosa and Santalum, together with an abundance of epiphytic fungi and a
great diversity of ferns (Kemp, 1978). The evidence for high humidity at all of the
known Eocene sites is very high. There is evidence of a general cooling during the
Oligocene, although data are sparse. Nothofagus and Dacrydium are well represented
but diversity in the pollen spectrum is much lower than that of the Eocene (Kemp,
1978), suggesting that cool temperate conditions prevailed. Warm conditions may
have prevailed slightly longer in western than in eastern Australia, as tropical
rainforest affiliates were present at least until the upper Eocene (Kemp, 1981; Hos,
1975).

As far back as the Eocene there is evidence of localised grassland formation. At
the Hale River deposits in central Australia, grass pollen comprises 7 per cent of the
total pollen count (Trusswell & Harris, 1981). In samples of Miocene age, grass
pollen counts at some sites are as high as 10 per cent and Casuarina pollen is some—
times abundant, although cool temperate conditions are generally indicated by the
frequent dominance of Nothofagus and Dacrydium. Lange (1978) recorded from
near Woomera an assemblage of fruits assignable to Eucalyptus, Leptospermum,
Calothamnus, Melaleuca—Callistemon and Angophora. The fossil record for the
Miocene, while not giving clear evidence of extensive deserts similar to those of
today, does indicate the expansion of open forest vegetation and, given the accepted
bias of the fossil record towards wet environments, it seems likely that arid conditions
were present in the Miocene and perhaps even earlier.

Critical evolutionary studies have led to similar conclusions about the ages of
plant groups now common in the arid zone. Carolin (1981), partly from his studies in
Caryophyllaceae, has suggested that there has been an arid region in Australia since
the break-up of Gondwanaland early in the Tertiary, about 55 m.y. BP. Smith-White
and co-workers (1970) have similarly suggested that the complex evolutionary history
of Brachycome in Australia also favours the existence of some arid conditions
throughout the Tertiary. Long evolutionary histories in the arid zone have likewise
been suggested for Triodia (Jacobs, 1981) and Calotis (Stace, 1981). Conversely, sig—
nificant differentiation has occurred in groups such as the swamp plants of the genus
Sowerbaea (Stewart & Barlow, 1976b), which have a disjunct circumcoastal distribu—
tion. This suggests that a considerable time has elapsed since a former Australia-wide
range was disrupted by aridity.

While parts of the eremean flora may therefore be older than formerly thought,
this may not be true for all components. Carolin (1981) has maintained that the trop—
ical lowland component may be a recent coloniser of the arid zone, Australia having
been in the correct climatic position for this development only since the Pliocene.
This view is consistent with the pattern for the onset of aridity in Australia suggested
by Bowler (1981).

Even though there is now reasonable evidence for the evolution of an eremean
flora in Australia over a period of at least 15 million years, and perhaps twice that
period of time, there is remarkably little evidence that the arid zone has functioned as
a major centre of species radiation. In an elegant analysis of relationships of Acacia,
Maslin and Hopper (1981) have indicated that the nearest relatives of adapted arid

Origin and Evolution

zone Acacia species are mostly to be found in adjacent temperate areas. Numerous
parallel lines of adaptation to aridity thus exist, rather than a single line leading to
the explosive radiation of a new arid species group. A similar situation almost cer—
tainly exists in Eremophila, Australian Euphorbieae (Hassall, 1981), Dodonaea
(West, 1981), Gnaphaliinae (Short, 1981), Calotis (Stace, 1981) and other plant
groups. It is also paralleled by similar evolutionary patterns in vertebrate and inverte—
brate animal groups (Baverstock, 1981; Greenslade, 1981). The arid zone thus
emerges as an area which has been colonised sucessfully by numerous biotypes
selected from adjacent populations growing under more favourable conditions, not as
a floristic zone in which internal evolutionary radiation has produced its own
characteristic flora.

The most conspicuous group for which this generalisation does not apply is the
Chenopodiaceae. Genera such as Sclerolaena and Maireana (previously known in
Australia as Bassia and Kochia repectively) have apparently radiated widely in arid
habitats. In Atriplex all the Australian species appear to be derived from a common
specialised immigrant ancestral type, except for one coastal species which may be a
separate introduction (Parr-Smith, 1981). Several species-clusters have evolved in arid
and semi-arid Australia from this ancestral type, all with a distinctive ovule orienta—
tion and all with the C, dicarboxylic acid metabolism and Kranz anatomy.

The importance of recent cycles of aridity is not completely negated by the
extension of the age of the arid zone into earlier Tertiary time. Even an adapted
desert flora would have been greatly disrupted by periods of extreme aridity, and the
present-day distribution of desert plants is clearly a result of climatic events of the
last few thousand years. Cycles of aridity were originally thought to be associated
with glacial cycles, such that glacial maxima were pluvial and interglacials were arid.
This view is now outmoded (Galloway & Kemp, 1981), and in fact aridity seems
often to be associated with lowered temperatures. The time of the last arid maximum
in south-eastern Australia is now put at 17 500-16 000 years BP (Bowler, 1978). It
may have been followed by a relatively pluvial phase culminating about 3 500
years BP (Gill, 1955), with conditions subsequently moving again towards aridity. In
the drier periods the arid flora, especially of stony soils, may have been reduced to
mountain refuges and peripheral habitats (Carolin, 1981), with subsequent recoloni—
sation very much dependent on the adaptive potential and competitive abilities of the
species involved.

Good evidence for episodic evolution in the arid zone is found in the work of
Randell (1970) on the genus Cassia. The arid zone species of Cassia have been de-
rived from tropical lowland ancestors and have undergone a significant radiation in
the Australian inland, coupled with extensive polyploidy at the highest level known
for this large pantropical genus. The known diploids occur in or near mountain
systems in central and southern Australia which could have been refugia. The most
recent range extensions on the arid plains have been by polyploid biotypes, and very
extensive hybridisation has occurred where these colonisers have come togetheg,
Similarly in the Eremophila glabra complex (Ey & Barlow, 1972) diploid biotypes
occur in mountain refugia and at the southern margins of the distribution of the
complex, while tetraploid and hexaploid biotypes are widespread in the interior.

Dune systems in Australia at the present time are generally stabilised. The last
period of widespread dune evolution probably coincided with the last glaciation
(Galloway & Kemp, 1981). It extended an edaphic feature which has probably existed
for 300 000 years and which has its own adapted plant associations, but it also
increased the disjunctions between other associations of the interior. Randell and

Origin and Evolution

Symon (1977), for example, have drawn attention to the disjunct distributions in
species of Cassia and Solanum, determined by the distribution of sand desert.

Mechanisms of evolution

The cytogenetic basis of biotype selection has been examined in a number of arid
zone genera. The most common cytoevolutionary syndrome is undoubtedly poly—
ploidy, which has been recorded in most of the genera in which broad surveys have
been undertaken. It has been reported in 19 out of 69 taxa in Eremophila (Barlow,
1971). In Cassia (Randell, 1970) polyploidy was found to be very frequent, with the
persistence of polyploid types with reduced sexual fertility achieved through an apo—
mictic system based on adventitious embryony. Polyploidy has also been reported in
Solanum (Randell & Symon, 1976), Ptilotus (Stewart & Barlow, 1976), Atriplex
(Parr-Smith, 1981), Brachycome (Carter, 1978b; Smith-White et al., 1970), Calotis
(Stace, 1978), Euphorbia (Hassall, 1977), Hibiscus (Menzel & Martin, 1980),
Goodenia (Peacock, 1963), Themeda (Hayman, 1960), Erodium (Carolin, 1958) and
Brunonia (Peacock & Smith-White, 1978). These genera show a variety of geograph—
ical patterns for the polyploid derivatives, and even in some cases the arid zone pop—
ulations are the residual diploid ones.

Barlow (1969, 1981b) has pointed out that much of the polyploidy in the arid
zone flora occurs at the infraspecific level and has thus occurred after the major
period of species differentiation in the eremean flora. Polyploidy may be generally
associated with the biotype selection which has accompanied the cycles of aridity in
Quaternary time, as has already been suggested above for Cassia and Eremophila.
Barlow (1971, 1981b) has also pointed out that in a number of cases the diploid races
are found in Western Australia, with polyploids extending eastwards into the interior,
suggesting that polyploids have replaced diploids in those areas where climatic fluc—
tuations or stresses may have been greatest.

The role of polyploidy is thought to be one of genetic conservation of new adap-
tive biotypes (Barlow, 1981b; James, 1981). This is achieved through restriction of
gene exchange between different ploidy levels and through its dampening effect on
phenotypic segregation. Polyploidy thus allows a new biotype to maximise its
production of genetically similar offspring.

Genomic changes other than polyploidy have been reported rarely for arid zone
plants. Widespread aneuploidy has been reported in Gnaphaliinae (Asteraceae) by
Short (cited by Barlow, 1981b) and in Calotis by Stace (1978), who pointed out that
aneuploid reduction without compensating change in chiasma frequency may be a
device which reduces genetic recombination to an acceptable level for biotypes which
have adopted an annual or ephemeral habit. In /sotoma, structural change involving
the accumulation of reciprocal translocations and a balanced lethal system has led to
permanent hybridity (James, 1965, 1970). James has argued that this genetic system
has been a response to inbreeding imposed by an increase in aridity in the species
range.

Studies in Brachycome by Smith-White and colleagues have revealed remarkable
cyogenetic adaptations. Extensive dysploidy, from n=2 to n=15, has occurred in
parallel series from a base number of x=9 (Smith-White et al., 1970). Infraspecific
genomic variation occurs in nucleolar organising regions, in timing of chromatin con—
densation and by interchange (Watanabe et al., 1975), and through supernumerary
chromosomes (Carter & Smith-White, 1972; Carter, 1978a). The most exceptional
work, however, has been in the B. /inearifolia species complex, where a strong cor—
relation has been discovered between change in genome constitution and altered eco—
logical tolerances towards aridity. A diploid race (2n =8) occupies coastal habitats on

Origin and Evolution

western Eyre Peninsula. Sympatric with it but extending further inland is a quasi-
diploid race with 2n=10 in which there are two different additional chromosomes
which are transmitted via the pollen (Carter et al., 1974). This race has a small zone
of overlap with a third race, having 22 =12, in which the additional chromosomes are
present in diploid dose (Kyhos et al., 1977). Finally, the race occurring furthest
inland is an apparent amphidiploid with 2n=16, in which the constituent genomes
have been derived by hybridisation of the third race just mentioned and a race of B.
dichromosomatica with 2n=4. The authors drew attention to a progressive increase
in growth vigour of these races and suggested that the successive addition of chromo—
somes is associated with an increasing tolerance of arid conditions.

The cytogenetic patterns described above clearly illustrate the responses in genetic
systems which are involved in adaptation to fluctuating environmental conditions, and
particularly to aridity. Their significance under conditions of rapid change, as has
occurred in the arid region of Australia in the Quaternary, may be especially great.
However it has been pointed out by Barlow (1981b) that gross alterations in the gen—
ome are not essential for the conservation of differentiating biotypes, and that the
incidence of such changes in the arid zone may be no greater than in other ecological
situations or in other periods of time.

Pollination and breeding systems

Adaptation for arid conditions has involved some predictable shifts in the fre—
quencies of the various pollination mechanisms. Keighery (1981) made a general
analysis of the eremean flora of Western Australia in comparison with that of adja—
cent temperate and tropical regions. He reported a general increase in wind- and bee-
pollination in the transition from temperate to eremean habitats. Bird-pollination
declined dramatically, and pollination by non-flying mammals disappeared com—
pletely, even though both of these pollination syndromes are important in the Aust—
ralian flora as a whole (Armstrong, 1979). In the latter case the shift is due to a
general absence of the pollinators, but this is not true of nectivorous birds. Among
entomophilous types there is a general decline in all pollinators except bees and bee
flies. Keighery pointed out that these pollinator shifts are consistent with a shift to
smaller flowers, which may be more economical with respect to nectar production
and water conservation.

Keighery (1981) also noted a shift towards self-compatibility in the eremean flora.
He suggested that the unpredictable environment of the arid zone has had a second
effect in addition to restricting the diversity of pollinators and pollination syndromes.
The second effect is a shift to self-compatibility as a ‘fail-safe’ reproductive system
countering pollinator unpredictability, even though the species involved are generally
adapted for outbreeding.

The Australian flora — a national heritage

The uniqueness of the Australian flora is clearly a matter of degree. As a whole, the
flora can be seen primarily as part of an extensive southern hemisphere flora in which
certain features are rather uniform. For example, its dominant temperate flowering
trees are evergreen, whereas those of the northern hemisphere are mostly deciduous.
This feature has been discussed by Axelrod (1966), who attributed the difference to
the palaeoclimatic conditions under which northern and southern temperate floras
evolved. The southern flora lacks the conifers which dominate cooler plant associa—
tions in the north. In respects such as this, the Australian flora is a typical sample of
southern hemisphere vegetation.

Origin and Evolution

A closer study reveals the unique characteristics of the flora, extending to vir—
tually all plant communities. Our arid zone is not matched in extent by any other
desert region south of the equator. It has a unique combination of cosmopolitan and
ancient Australian plants, many of which are susceptible to replacement by intro-
duced aliens better adapted phenologically, and many of which cannot withstand
intensive pastoral activity. It differs from other deserts in having very few succulent
xerophytes; most of its woody plants are drought resisters with a physiological capa—
city to endure dehydration; and it has a beautiful ephemeral flora which is rarely seen
and includes threatened species (Specht et al., 1974). The alpine habitat in Australia
is very limited in extent, and carries a rare combination of ancient southern plants
and adapted Australian ones distributed above a tree line which is remarkably low
because of the lack of conifers or frost-hardy angiosperms in Australia. Elsewhere in
eastern and south eastern Australia, and especially in south western Australia, the
scleromorphic floras of poor soils and seasonal habitats are bewildering in their diver—
sity; they are matched in diversity (but not in composition) only by the Cape flora of
South Africa (Johnson & Briggs, 1981). As mentioned above, endemism in these
floras is very high, so that numerous species are confined to very small areas.

Because of a growing community awareness of the special character of our plant
associations, a number of effective conservation measures have been taken. Up to
now, however, much of this action has been directed towards protection of selected
communities in selected locations, often associated with spectacular scenery or with
recreational sites. The conservation of whole floristic elements as a whole should be
considered as a matter of principle, especially where we recognise them to be relict
with a slender tenure on survival. This approach is already being made, for example,
in Western Australia (Anon., 1974). Further action must follow as our understanding
of the composition, history and relationships of the surviving natural plant communi—
ties continues to grow.

The need for this action can be illustrated by example. The temperate and sub-
tropical rainforests of eastern Australia survive today in a number of isolated pockets
scattered along the coast and ranges, and their total area has been considerably
reduced both by logging and by clearing for pastoral activity. According to our for—
mer view of Australian biogeography, these communities would have been seen as
modern invaders (in the sense of geological time) of the Australian flora—almost as
prehistoric aliens supplanting our truly Australian vegetation. We now see these rain—
forests as the remnants, in Australia, of the ancient Gondwanan flora which covered
the entire continent when it was still attached to Antarctica sixty million years ago.
They are the surviving residue of the primitive stocks from which the bulk of the
modern Australian flora has been derived. This residue comprises the taxa which
have undergone the least evolutionary change and includes some of the most primi-
tive genera of flowering plants still surviving in the world. These are the most ancient
Australians still surviving. Perhaps, with such an understanding of the history of these
forests and with awareness of their intrinsic beauty, we should consider, as a matter
of national pride, conserving all that remains of them.

The Australian flora, as we see it today, thus tells the story of a hundred million
years of history of Australia as a southern land mass. The alien plants which have
become naturalised so widely since European settlement are legitimately included in
the Australian flora. Their impact on the flora, however great, has nevertheless
occurred almost instantaneously in terms of the long history of colonisation of the
continent by plants.

Origin and Evolution

References

Andrews, E. C. (1916), The geological history of the Australian flowering plants,
Amer. J. Sci. 42: 171-232.

Anonymous (1974), Conservation Reserves in Western Australia, Report of the
Conservation Through Reserves Committee to the Environmental Protection
Authority (of Western Australia).

Armstrong, J. A. (1979), Biotic pollination mechanisms in the Australian flora—a
review, New Zealand J. Bot. 17: 467-508.

Audley-Charles, M. G., Carter, D. J. & Milsom, J. S. (1972), Tectonic development
of eastern Indonesia in relation to Gondwanaland dispersal, Nature Phys. Sci.
239: 35-39.

Axelrod, D. I. (1966), Origin of deciduous and evergreen habits in temperate forests,
Evolution 20: 1-15.

Baker, H. G. (1967), Support for Baker’s Law—as a rule, Evolution 21: 853-856.

Barlow, B. A. (1959), Chromosome numbers in the Casuarinaceae, Austral. J. Bot. 7:
230-237.

Barlow, B. A. (1963), Studies in Australian Loranthaceae, IV. Chromosome numbers
and their relationships, Proc. Linn. Soc. New South Wales 88: 151-160.

Barlow, B. A. (1969), Infraspecific polyploidy in Eremophila, Austral. J. Sci. 31:
431-432.

Barlow, B. A. (1971), Cytogeography of the genus Eremophila, Austral. J. Bot. 19:
295-310.

Barlow, B. A. (1972), The significance of Torres Strait in the distribution of
Australasian Loranthaceae, in D. Walker, Bridge and Barrier: the Natural and
Cultural History of Torres Strait, Publ. BG/3. Australian National University,
Canberra.

Barlow, B. A. (198la), The loranthaceous mistletoes in Australia, “in A. Keast,
Ecological Biogeography of Australia. W. Junk, The Hague.

Barlow, B. A. (1981b), Cytogenetic systems in Australian arid zone plants, in W. R.
Barker, P. J. M. Greenslade & P. R. Baverstock, Evolution of the Flora and
Fauna of Arid Australia, Symposium, Adelaide, May 1980. In press.

Barlow, B. A. & Wiens, D. (1971), The cytogeography of the loranthaceous mistle—
toes, Taxon 20: 291-312.

Baverstock, P. R. (1981), Adaptations and radiations of mammals in arid Australia,
in W. R. Barker, P. J. M. Greenslade & P. R. Baverstock, Evolution of the
Flora and Fauna of Arid Australia, Symposium Adelaide, May 1980. In press.

Beadle, N. C. W. (1954), Soil phosphate and the delimitation of plant communities”
in eastern Australia, Ecology 35: 370-375.

Beadle, N. C. W. (1966), Soil phosphate and its role in molding segments of the
Australian flora and vegetation, with special reference to xeromorphy and sclero—
phylly, Ecology 47: 992-1007.

Beadle, N. C. W. (1968), Some aspects of ecology and physiology of Australian
xeromorphic plants, Austral. J.Sci. 30: 348-355.

Beadle, N. C. W. (1981), Origins of the Australian angiosperm flora, in A. Keast,
Ecological Biogeography of Australia. W. Junk, The Hague.

Origin and Evolution

Beard, J. S. (1969), Endemism in the Western Australian flora at species level, J.
Roy. Soc. W. Austral. 52: 18-20.

Beard, J. S. (1976), The evolution of Australian desert plants, in D. W. Goodall,
Evolution of Desert Biota. University of Texas Press, Austin.

Bowler, J. M. (1978), Quaternary climate and tectonics in the evolution of the River—
ina plain, south-eastern Australia, in J. L. Davies & M. A. J. Williams,
Landform Evolution in Australia. Australian National University Press, Canberra.

Bowler, J. M. (1981), Age, origin and landform expression of aridity in Australia, in
W. R. Barker, P. J. M. Greenslade & P. R. Baverstock Evolution of the Flora
and Fauna of Arid Australia, Symposium. Adelaide, May 1980. In press.

Brenner, G. J. (1976), Middle Cretaceous floral provinces and early migrations of
angiosperms, in C. B. Beck, Origin and Early Evolution of Angiosperms.
Columbia University Press, New York.

Briggs, B. G. (1963), Chromosome numbers in Lepyrodia and Restio in Australia,
Contrib. New South Wales Nat. Herb. 3: 129-150.

Burbidge, N. T. (1960), The phytogeography of the Australian region, Austral. J. Bot.
8: 75-212.

Cain, S. A. (1944), Foundations of Plant Geography. Harper & Row, New York.

Camp, W. H. (1947), Distribution patterns in modern plants and the problems of
ancient dispersals, Ecol. Monogr. 17: 159-183.

Camp, W. H. (1952), Phytophyletic patterns on lands bordering the south Atlantic
basin, Bull. Amer. Mus. Nat. Hist. 99: 205-212.

Carolin, R. C. (1958), The species of the genus Erodium L’Her. endemic in Aust-—
ralia, Proc. Linn. Soc. New South Wales 83: 92-100.

Carolin, R. C. (1981), The development of the biogeography of arid Australia, in
W. R. Barker, P. J. M. Greenslade & P. R. Baverstock, Evolution of the Flora
and Fauna of Arid Australia, Symposium, Adelaide, May 1980. In press.

Carlquist, S. (1966), The biota of long-distance dispersal. I. Principles of dispersal and
evolution, Quart. Rev. Biol. 41: 247-270.

Carter, C. R. (1978a), The cytology of Brachycome. 8. The inheritance, frequency
and distribution of B chromosomes in B. dichromosomatica(n=2), formerly
included in B. /ineariloba, Chromosoma (Berl.) 67: 109-121.

Carter, C. R. (1978b), The cytology of Brachycome. LU. The subgenus Meta-
brachycome: a general survey, Austral. J. Bot. 26: 699-706.

Carter, C. R. & Smith-White, S. (1972), The cytology of Brachycome lineariloba.
3. Accessory chromosomes, Chromosoma (Berl.) 39: 361-379.

Carter, C. R., Smith-White, S. & Kyhos, D. W. (1974), The cytology of Brachycome
lineariloba. 4. The 10-chromosome quasi-diploid, Chromosoma (Berl.) 44: 439-
456.

Clifford, H. T. & Simon, B. K. (1981), The biogeography of Australian grasses, in
A. Keast, Ecological Biogeography of Australia. W.. Junk, The Hague.

Coleman, P. J. (1980), Plate tectonics background to biogeographic development in
the southwest pacific over the last 100 million years, Palaeogeography, Palaeo—
climatology, Palaeoecology 31: 105-121.

Origin and Evolution

Crocker, R. L. (1957), Past climatic fluctuations and their influence upon Australian
vegetation, in A. Keast, Biogeography and Ecology of Australia. W. Junk, The
Hague.

Crocker, R. L. & Wood, J. G. (1947), Some historical influences on the development
of South Australian vegetation communities and their bearing on concepts and
classification in ecology, Trans. Roy. Soc. S. Austral. 71: 91-136.

Croizat, L. (1952), Manual of Phytogeography; or an Account of Plant-dispersal
throughout the World. W. Junk, The Hague.

Cronquist, A. (1968), The Evolution and Classification of Flowering Plants. Nelson,
London.

Crook, K. A. W. (1981), The break-up of the Australian-Antarctic segment of
Gondwanaland, in A. Keast, Ecological Biogeography of Australia. W. Junk, The
Hague.

Dettmann, M. E. (1981), The Cretaceous flora, in A. Keast, Ecological Biogeo-
graphy of Australia. W. Junk, The Hague.

Diels, L. (1906), Die Pflanzenwelt von West Australien. Englemann, Leipzig.

Doutch, H. F. (1972), The paleogeography of northern Australia and New Guinea
and its relevance to the Torres Strait area, in D. Walker, Bridge and Barrier: the
Natural and Cultural History of Torres Strait, Publ. BG/3. Australian National
University, Canberra.

Erickson, R. (1958), Triggerplants. Brokensha, Perth.

Ey, T. M. & Barlow, B. A. (1972), Distribution of chromosome races in the Ere-
mophila glabra complex, Search 3: 337-338.

Farrell, P. G. & James, S. H. (1979), Stylidium ecorne (F. Muell. ex Erickson and
Willis) comb. et stat. nov. (Stylidiaceae), Austral. J. Bot. 27: 39-45.

Fosberg, F. R. (1948), Derivation of the flora of the Hawaiian Islands, in E. C.
Zimmerman, /nsects of Hawaii. University of Hawaii Press, Honolulu.

Galloway, R. W. & Kemp, E. M. (1981), Late Cainozoic environments in Australia.
in A. Keast, Ecological Biogeography of Australia. W. Junk, The Hague.

Galloway, R. W. & Loffler, E. (1972), Aspects of geomorphology and soils in the
Torres Strait region, in D. Walker, Bridge and Barrier: the Natural and Cultural
History of Torres Strait, Publ. BG/3. Australian National University, Canberra.

Gardner, C. A. (1944), The vegetation of Western Australia, J. Roy. Soc. W. Austral.
28: xi-Ixxxvii.

George, A. S. (1976), Biogeography of Banksia (Proteaceae), 47th ANZAAS Con-
gress, Abstr. 179.

Gill, A. M. (1975), Fire and the Australian flora: a review, Austral. For. 39: 4-25. ~™
Gill, E. D. (1955), The Australian arid period, Austral. J. Sci. 17: 204-206.

Gill, E. D. (1962), Cainozoic, in A. Spry & M. R. Banks, The geology of Tasmania,
J. Geol. Soc. Austral. 9: 233-254.

Gill, E. D. (1975), Evolution of Australia’s unique flora and fauna in relation to the
plate tectonics theory, Proc. Roy. Soc. Victoria 87: 215-234.

Good, R. (1947) The Geography of the Flowering Plants. Longmans Green, London.

Origin and Evolution

Good, R. (1960), On the geographical relationships of the angiosperm flora of New
Guinea, Bull. Brit. Mus. (Nat. Hist.), Bot. 2: 205-226.

Good, R. (1963), On the biological and physical relationships between New Guinea
and Australia, in J. L. Gressit, Pacific Basin Biogeography. Bishop Museum
Press, Honolulu.

Grady, A. E. & Berry, R. F. (1977), Some Palaeozoic-Mesozoic stratigraphic-
structural relationships in east Timor and their significance in the tectonics of
Timor, J. Geol. Soc. Austral. 24: 203-214.

Greenslade, P. (1981), Origins of the Collembolan fauna of arid Australia, in W. R.
Barker, P. J. M. Greenslade & P. R. Baverstock, Evolution of the Flora and
Fauna of Arid Australia, Symposium. Adelaide, May 1980. In press.

Griffiths, J. R. & Varne, R. (1972), Evolution of the Tasman Sea, Macquarie Ridge,
and Alpine Fault, Nature Phys. Sct. 235: 83-86.

Hassall, D. C. (1977), The genus Euphorbia in Australia, Austral. J. Bot. 25:
429-453.

Hassall, D. C. (1981), Historical development in the Australian Euphorbieae
(Euphorbiaceae), in W. R. Barker, P. J. M. Greenslade, & P. R. Baverstock,
Evolution of the Flora and Fauna of Arid Australia, Symposium, Adelaide, May
1980. In press.

Hayman, D. L. (1960), The distribution and cytology of the chromosome races of
Themeda australis in southern Australia, Austral. J. Bot. 8: 58-68.

Herbert, D. A. (1932), The relationships of the Queensland flora, Proc. Roy. Soc.
Queensland 44: 2-22.

Herbert, D. A. (1935), The climatic sifting of Australian vegetation, ANZAAS Rep.
22: 349-370.

Herbert, D. A. (1950), Present day distribution and the geological past, Victorian
Naturalist 66: 227-232.

Herbert, D. A. (1960), Tropical and sub-tropical rainforest in Australia, Austral. J.
Sci. 22: 283-290.

Herbert, D. A. (1964), Differentiation of paleotropical floras, Advancing Frontiers PI.
Sci. 1: 51-59.

Herbert, D. A. (1967), Ecological segregation and Australian phytogeographic ele—
ments, Proc. Roy. Soc. Queensland 78: 101-111.

Hoogland, R. D. (1972), Plant distribution patterns across the Torres Strait, in
D. Walker, Bridge and Barrier: the Natural and Cultural History of Torres Strait,
Publ. BG/3. Australian National University, Canberra.

Hooker, J. D. (1860), Introductory Essay, Botany of the Antarctic Voyage of H.M.
Discovery ships ‘Erebus’ and ‘Terror’ in the years 1839-1843, Ill. Flora
Tasmaniae, Reeve, London.

Hopper, S. D. (1979), Biogeographical aspects of speciation in the southwest
Australian flora, Annual Rev. Ecol. Syst. 10: 399-422.

Hos, D. (1975), Preliminary investigation of the palynology of the Upper Eocene
Werillup Formation, Western Australia, J. Roy. Soc. W. Austral. 58: 1-14.

Jacobs, S. W. L. (1981), Relationships, distribution and evolution of Triodia and
Plectrachne (Gramineae), in W. R. Barker, P. J. M. Greenslade, & P. R.

Origin and Evolution

Baverstock, Evolution of the Flora and Fauna of Arid Australia, Symposium,
Adelaide, May 1980. In press.

James, S. H. (1963), Cytological studies in the Lobeliaceae, Ph.D. thesis, University
of Sydney, Sydney.

James, S. H. (1965), Complex hybridity in Jsotoma petraea. 1. The occurrence of
interchange heterozygosity, autogamy and a balanced lethal system, Heredity 20:
341-353.

James, S. H. (1970), Complex hybridity in /sotoma petraea. I]. Components and
operation of a possible evolutionary mechnism, Heredity 25: 53-78.

James, S. H. (1979), Chromosome numbers and genetic systems in the trigger-plants
of Western Australia (Stylidium; Stylidiaceae), Austral. J. Bot. 27: 17-25.

James, S. H. (1981), Cytoevolutionary patterns, genetic systems and the phytogeo-
graphy of Australia, in A. Keast, Ecological Biogeography of Australia. W. Junk,
The Hague.

Jardine, N. & McKenzie, D. (1972), Continental drift and the dispersal and evolution
of organisms, Nature 235: 20-24.

Jennings, J. N. (1972), Some attributes of Torres Strait, in D. Walker, Bridge and
Barrier: the Natural and Cultural History of Torres Strait, Publ. BG/3. Australian
National University, Canberra.

Johnson, L. A. S. (1976), Problems of genera and species in Eucalyptus (Myrtaceae),
Pl. Syst. Evol. 125: 155-167.

Johnson, L. A. S. & Briggs, B. G. (1975), On the Proteaceae—the evolution and
classification of a southern family, Bot. J. Linn. Soc. 70: 83-122.

Johnson, L. A. S. & Briggs, B. G. (1981), Three old southern families—Myrtaceae,
Proteaceae and Restionaceae, in A. Keast, Ecological Biogeography of Australia.
W. Junk, The Hague.

Keast, A. (1958), The influence of ecology on variation in the mistletoe-bird
(Dicaeum hirundinaceum), Emu 58: 195-206.

Keighery, G. J. (1981), Pollination syndromes and breeding systems of Western
Australian arid zone plants, in W. R. Barker, P. J. M. Greenslade, & P. R.
Baverstock, Evolution of the Flora and Fauna of Arid Australia, Symposium,
Adelaide, May 1980. In press.

Kemp, E. M. (1978), Tertiary climatic evolution and vegetation history in the
southeast Indian Ocean region, Palaeogeogr., Palaeoclimatol., Palaeoecol. 24:
169-208.

Kemp, E. M. (1981), Tertiary palaeogeography and the evolution of Australian
climate, in A. Keast, Ecological Biogeography of Australia. W. Junk, The Hague. |

Kemp, E. M. & Barrett, P. J. (1975), Antarctic glaciation and early Tertiary
vegetation, Nature 258: 507-508.

Krassilov, V. A. (1977), The origin of angiosperms, Bot. Rev. 43: 143-176.

Kyhos, D. W., Carter, C. R. & Smith-White, S. (1977), The cytology of Brachycome
lineariloba. 7. Meiosis in natural hybrids and race relationships, Chromosoma
(Berl.) 65: 81-101.

Lange, R. T. (1978), Carpological evidence for fossil Eucalyptus and other
Leptospermeae (subfamily Leptospermoideae of Myrtaceae) from a Tertiary
deposit in the South Australian arid zone, Austral. J. Bot. 26: 221-233.

Origin and Evolution

Loveless, A. R. (1961), A nutritional interpretation of sclerophylly based on dif-
ferences in the chemical composition of sclerophyllous and mesophytic leaves,
Ann. Bot. (London), n.s. 25: 168-184.

Maconochie, J. R. (1979), Phenology of Central Australian arid zone plants, Symp.
Biol. Native Austral. P/., Perth.

Marchant, N. G. (1973a), Species diversity in the south-western flora, J. Roy. Soc.
W. Austral. 56: 23-30.

Marchant, N. G. (1973b), Speciation in Drosera, Section Lamprolepis, ANZAAS
45th Congress, Sect. 12 Abstr.

Martin, H. A. (1981), The Tertiary flora, in A. Keast, Ecological Biogeography of
Australia. W. Junk, The Hague.

Maslin, B. R. & Hopper, S. D. (1981), Phytogeography of Acacia (Leguminosae:
Mimosoideae) in Central Australia, in W. R. Barker, P. J. M. Greenslade, &
P. R. Baverstock, Evolution of the Flora and Fauna of Arid Australia,
Symposium, Adelaide, May 1980. In press.

McKenna, M. C. (1972), Possible biological consequences of plate tectonics, Bio-
Science 22: 519-525.

Menzel, M. Y. & Martin, D. W. (1980), Evidence for the presence of an inter—
continental genome in the Australian hexaploid alliance of Aibiscus Sect. Fur-
caria, Austral. J. Bot. 28: 369-383.

Nelson, E. C. (1981), Phytogeography of southern Australia, in A. Keast, Ecological
Biogeography of Australia. W. Junk, The Hague.

Nix, H. A. (1981), Environmental determinants of biogeography and evolution in
arid Australia, in W. R. Barker, P. J. M. Greenslade, & P. R. Baverstock,
Evolution of the Flora and Fauna of Arid Australia, Symposium, Adelaide, May
1980. In press.

Nix, H. A. & Kalma, J. D. (1972), Climate as a dominant control in the
biogeography of northern Australia and New Guinea, in D. Walker, Bridge and
Barrier: the Natural and Cultural History of Torres Strait, Publ. BG/3, Australian
National University, Canberra.

Page, C. N. & Clifford, H. T. (1981), Ecological biogeography of Australian conifers
and ferns, in A. Keast, Ecological Biogeography of Australia. W. Junk, The
Hague.

Parr-Smith, G. A. (1981), Biogeography and evolution in the shrubby Australian
Atriplex (Chenopodiaceae), in W. R. Barker, P. J. M. Greenslade, & P. R.
Baverstock, Evolution of the Flora and Fauna of Arid Australia, Symposium,
Adelaide, May 1980. In press.

Peacock, W. J. (1963), Chromosome numbers and cytoevolution in the Goodeni-—
aceae, Proc. Linn. Soc. New South Wales 88: 8-27.

Peacock, W. J. & Smith-White, S. (1978), Cytogeography of Brunonia australis Sm.
ex R. Br., Brunonia 1: 31-43.

Powell, C. McA., Johnson, B. D. & Veevers, J. J. (1981), The Early Cretaceous
break-up of Eastern Gondwanaland, the separation of Australia and India, and
their interaction with Southeast Asia, in A. Keast, Ecological Biogeography of
Australia. W. Junk, The Hague.

Origin and Evolution

Preest, D. S. (1963), A note on the dispersal characteristics of the seed of the New
Zealand podocarps and beeches and their biogeographical significance, in J. L.
Gressitt, Pacific Basin Biogeography. Bishop Museum Press, Honolulu.

Pryor, L. D. (1976), The Biology of Eucalypts. Edward Arnold, London.

Pryor, L. D. & Johnson, L. A. S. (1981), Eucalyptus, the universal Australian, in
A. Keast, Ecological Biogeography of Australia. W. Junk, The Hague.

Ramsay, H. P. (1963), Chromosome numbers in the Proteaceae, Austral. J. Bot. 11:
1-20.

Randell, B. R. (1970), Adaptations in the genetic systems of Australian arid zone
Cassia species (Leguminosae, Caesalpinioideae), Austra/. J. Bot. 18: 77-97.

Randell, B. R. & Symon, D. E. (1976), Chromosome numbers in Australian Solanum
species, Austral. J. Bot. 24: 369-379.

Randell, B. R. & Symon, D. E. (1977), Distribution of Cassia and Solanum species
in arid Australia, Search 8: 206-207.

Raven, P. H. (1979), Plate tectonics and southern hemisphere biogeography, in
K. Larsen & L. B. Holm-Nielsen, Tropical Botany. Academic Press, London.

Raven, P. H. & Axelrod, D. I. (1972), Plate tectonics and Australasian biogeography,
Science 176: 1379-1386.

Raven, P. H. & Axelrod, D. I. (1974), Angiosperm biogeography and past contin—
ental movements, Ann. Missouri Bot. Gard. 61: 539-673.

Recher, H. F. & Christensen, P. E. (1981), Fire and the evolution of the Australian
biota, in A. Keast, Ecological Biogeography of Australia. W. Junk, The Hague.

Sands, V. E. (1975), The cytoevolution of the Australian Papilionaceae, Proc. Linn.
Soc. New South Wales 100: 118-155.

Schuster, R. M. (1976), Plate tectonics and its bearing on the geographical origin and
dispersal of angiosperms, in C. B. Beck, Origin and Early Evolution of
Angiosperms. Columbia Univ. Press, New York.

Schwarz, O. (1928), Analytische Studie iiber die Beziehungen der Phanerogamenflora
von Arnhemsland (Nordaustralien), Repert. Spec. Nov. Regn. Veg. Beth. 51:
59-113.

Short, P. S. (1981), Breeding systems and distribution patterns of some Australian
Gnaphaliinae (Compositae: Inuleae), in W. R. Barker, P. J. M. Greenslade, &
P. R. Baverstock, Evolution of the Flora and Fauna of Arid Australia,
Symposium, Adelaide, May 1980. In press.

Smith-White, S. (1948a), Cytological studies in the Myrtaceae II. Chromosome
numbers in the Leptospermoideae and Myrtoideae, Proc. Linn. Soc. New South
Wales 73: 16-36. +

Smith-White, S. (1948b), A survey of chromosome numbers in the Epacridaceae,
Proc. Linn. Soc. New South Wales 73: 37-56.

Smith-White, S. (1950), Cytological studies in the Myrtaceae HI. Cytology and
phylogeny of the Chamaelaucoideae, Proc. Linn. Soc. New South Wales 75:
99-121.

Smith-White, S. (1954a), Cytological studies in the Myrtaceae IV. The subtribe
Euchamaelaucinae, Proc. Linn. Soc. New South Wales 79: 21-28.

Origin and Evolution

Smith-White, S. (1954b), Chromosome numbers in the Boronieae (Rutaceae) and
their bearing on the evolutionary development of the tribe in the Australian flora,
Austral. J. Bot. 2: 287-303.

Smith-White, S. (1955), Chromosome numbers and pollen types in the Epacridaceae,
Austral. J. Bot. 3: 48-67.

Smith-White, S. (1959), Cytological evolution in the Australian flora, Cold Spring
Harbor Symp. Quant. Biol. 24: 273-289.

Smith-White, S., Carter, C. R. & Stace, H. M. (1970), The cytology of Brachycome.
1. The subgenus Eubrachycome: a general survey, Austral. J. Bot. 18: 99-125.
Specht, R. L. (1958), The geographical relationships of the flora of Arnhem Land, in
R. L. Specht & C. P. Mountford, Records of the American-Australian Scientific

Expedition to Arnhem Land. Melbourne University Press, Melbourne.

Specht, R. L. (1972), The Vegetation of South Australia. Government Printer,
Adelaide.

Specht, R. L. (1981a), Major vegetation formations in Australia, in A. Keast,
Ecological Biogeography of Australia. W. Junk, The Hague.

Specht, R. L. (1981b), Ecophysiological principles determining the biogeography of
major vegetation formations in Australia, in A. Keast, Ecological Biogeography of
Australia. W. Junk, The Hague.

Specht, R. L. (1981c), Evolution of the Australian flora: some generalizations, in
A. Keast, Ecological Biogeography of Australia. W. Junk, The Hague.

Specht, R. L., Rayson, P. & Jackman, M. (1958), Dark Island Heath (Ninety-Mile
Plain, South Australia). VI. Pyric succession; changes in composition, coverage,
dry wreight and mineral status, Austral. J. Bot. 6: 59-88.

Specht, R. L., Roe, E. M. & Boughton, V. H. (1974), Conservation of major plant
communities in Australia and Papua New Guinea, Austral. J. Bot. Suppl. Series
No. 7.

Stace, H. M. (1978), Cytoevolution in the genus Ca/otis R. Br. (Compositae:
Astereae), Austral. J. Bot. 26: 287-307.

Stace, H. M. (1981), Ca/otis R. Br. (Compositae), an old arid zone genus?, in
W. R. Barker, P. J. M. Greenslade, & P. R. Baverstock, Evolution of the Flora
and Fauna of Arid Australia, Symposium, Adelaide, May 1980. In press.

Stebbins, G. L. & Hoogland, R. D. (1976), Species diversity, ecology and evolution
in a primitive angiosperm genus: Hybbertia (Dilleniaceae), Pl Syst. Evol. 125:
139-154.

Steenis, C. G. G. J. van (1934a), On the origin of the Malaysian mountain flora. 1.
Facts and statement of the problem, Bul/. Jard. Bot. Buitenzorg 13: 139-262.

Steenis, C. G. G. J. van (1934b), On the origin of the Malaysian mountain flora. 2.
Altitudinal zones, general considerations and renewed statement of the problem,
Bull. Jard. Bot. Buitenzorg 13: 289-417.

Steenis, C. G. G. J. van (1936), On the origin of the Malaysian mountain flora. 3.
Analysis of floristic relationships. Pt. i. The Sumatran track, Bull. Jard. Bot.
Buitenzorg 14: 56-72.

Steenis, C. G. G. J. van (1950), The delimitation of Malaysia and its main plant
geographical divisions, in C. G. G. J. van Steenis (ed.), Flora Malesiana, Series
1, Spermatophyta Vol. 1: 1xx-lxxv. Noordhoff, Djakarta.

Origin and Evolution

Steenis, C. G. G. J. van (1963), Transpacific floristic affinities, particularly in the
tropical zone, in J. L. Gressitt, Pacific Basin Biogeography. Bishop Museum
Press, Honolulu.

Steenis, C. G. G. J. van (1971), Nothofagus, key genus of plant geography, in time
and space, living and fossil, ecology and phylogeny, Blumea 19: 65-98.

Steenis, C. G. G. J. van (1979), Plant-geography of east Malesia, Bot. J. Linn. Soc.
79: 97-178.

Stewart, D. A. & Barlow, B. A. (1976a), Infraspecific polyploidy and gynodioecism
in Ptilotus obovatus (Amaranthaceae), Austral. J. Bot. 24: 237-248.

Stewart, D. A. & Barlow, B. A. (1976b), Genomic differentiation and polyploidy in
Sowerbaea (Liliaceae), Austral. J. Bot. 24: 349-367.

Takhtajan, A. (1969), Flowering Plants, Origin and Dispersal. Oliver, Edinburgh.
Tate, R. (1888), Presidential address, Austral. Assoc. Adv. Sci., Report 1: 317-319.

Thomson, M. R. A. & Burn, R. W. (1977), Angiosperm fossils from latitude 70° S,
Nature 269: 139-141.

Trusswell, E. M. & Harris, W. K. (1981), The Cainozoic palaeobotanical record in
arid Australia: fossil evidence for the origins of an arid-adapted flora, in W. R.
Barker, P. J. M. Greenslade, & P. R. Baverstock, Evolution of the Flora and
Fauna of Arid Australia, Symposium, Adelaide, May 1980. In press.

Turner, B. L. (1966), Chromosome numbers in Stackhousia (Stackhousiaceae),
Austral. J. Bot. 14: 165-166.

Wace, N. M. (1972), Discussion on the plant geography around Torres Strait, in
D. Walker, Bridge and Barrier: the Natural and Cultural History of Torres Strait,
Publ. BG/3. Australian National University, Canberra.

Watanabe, K., Carter, C. R. & Smith-White, S. (1975), The cytology of Brachycome
lineariloba. 6. Asynchronous chromosome condensation and meiotic behaviour in
B. lineariloba A (n=2) X B. campylocarpa A (n=4), Chromosoma (Berl.) 57:
319-331.

Webb, L. J. & Tracey, J. G. (1972), An ecological comparison of vegetation
communities on each side of Torres Strait in D. Walker, Bridge and Barrier: the
Natural and Cultural History of Torres Strait, Publ. BG/3. Australian National
University, Canberra.

Webster, P. J. & Streten, N. A. (1972), Aspects of late Quaternary climate in
tropical Australasia, in D. Walker, Bridge and Barrier: the Natural and Cultural
History of Torres Strait, Publ. BG/3. Australian National University, Canberra.

Weissel, J. K. & Hayes, D. E. (1974), The Australian-Antarctic discordance, new
results and implications, J. Geophys. Res. 79: 2579-2587.

West, J. G. (1980), A taxonomic revision of Dodonaea Miller (Sapindaceae) in
Australia, Ph.D. thesis, University of Adelaide.

West, J. G. (1981), Radiation and adaptations of Dodonaea Miller (Sapindaceae) in
arid Australia, “mn W. R. Barker, P. J. M. Greenslade, & P. R. Baverstock,
Evolution of the Flora and Fauna of Arid Australia, Symposium, Adelaide, May
1980. In press.

Wopfner, H., Callen, R. & Harris, W. K. (1974), The lower Tertiary Eyre Formation
of the southwestern Great Artesian Basin, J. Geol. Soc. Austral. 21: 17-52.

AN INTRODUCTION TO THE
SYSTEM OF CLASSIFICATION USED IN THE
FLORA OF AUSTRALIA

A. Kanis

Floras and the classification of plants

Floras are works of reference about plants, arranged in systematic categories (‘taxa’),
of defined geographical areas. Because they vary in the amount of detail included as
well as the size and complexity of the area covered, they can differ considerably in
size and format. In handbooks and more comprehensive floras particular attention is
given to the principal means of plant identification, viz. keys and comparable descrip—
tions of taxa, largely based on morphological characters. The taxon most commonly
recognised, and therefore emphasised in Floras, is the species (‘kind’ or ‘sort’). In
works of a critical nature, almost equivalent attention may be given to such infra-
specific categories as subspecies and varietas (‘variety’). No doubt this is for the
practical reason that the information most frequently required is about species and
subordinate taxa.

In accordance with general principles of classification, the basic taxonomic cate—
gories are grouped into larger units: from many rather concretely defined ones to
fewer more generalised and therefore more abstract ones. The arrangement of indi—
vidual plants and populations into larger categories, on the basis of degrees of simi—
larity and of discontinuity in variation, results in a hierarchical system. The informa—
tion presented in floras is arranged in accordance with such a system, because it
facilitates comparisons if similar taxa are treated in close proximity.

Not all taxa that may be distinguished above the rank of species are of equal
interest. Certain ranks are traditionally given greater prominence than others in floras,
sometimes to the complete exclusion of intermediate ones. The next category of
practical importance above species is that of genus. Although essentially more
theoretical in concept, genera are often more readily recognised than their composite
taxa. A generic name (always treated as a Latin singular noun though frequently of
Greek or other derivation) forms the first part of a binary name which is given to
every species. The second part is the so-called ‘specific epithet’, which is usually an
adjective. To denote a subspecies or a variety a third element, usually a second
adjective, is added to the name of the relevant species. As a result the very nomen—
clature of plants reflects a systematic arrangement, at least from the generic level
downwards.

The present concepts of genus, species and variety can be traced back to the
writings of the Swedish botanist Carl von Linné (1707-1778) better known as™
Linnaeus, although they were adapted and defined, rather than invented, by him.
Many of the genera and subordinate taxa recognised by Linnaeus have since been
widened or, more often, narrowed in their circumscription, but the great majority of
these have survived to form the core of all subsequent systems of classification. For
ranks above that of genus, Linnaeus deliberately used an artificial system of orders
and classes based on a minimum of arbitrarily chosen floral characters such as the
number of stamens and pistils (‘sexual system’). He regarded this as the most prac—
tical solution for classifying the avalanche of new plants reaching scientists in his day
from remote, newly explored parts of the world.

System of classification

The influence of the Linnaean system was so great that it largely discouraged the
development and use of alternatives for over half a century. As knowledge of the
world’s flora increased, however, botanists became better equipped to design so-called
‘natural systems’. These have been based on similarities and differences in as many
characters as possible, both vegetative and reproductive. The recognition of ‘natural
orders’ was strongly promoted in the latter part of the 18th Century by some French
botanists, of whom Antoine Laurent de Jussieu (1748-1836) was the most influential.
One of the very first floras in which genera were arranged by natural orders was also
the first concerned with the Australian region, viz. Robert Brown’s Prodromus Florae
Novae Hollandiae et Insulae Van-Diemen (1810). During the 19th Century it became
customary to replace the term ‘natural order’ by the alternative familia (‘family’), first
promoted by another Frenchman, Michel Adanson (1727-1806). Some families such
as Apiaceae (Umbelliferae), Brassicaceae (Cruciferae) and Poaceae (Gramineae)
were already recognised as natural groups by some of Linnaeus’ predecessors and are
therefore older than the formal category itself. Family names are of practical use
because they can be remembered more easily, being rather fewer in number than
their included genera. This advantage, however, is somewhat eroded by the trend to
divide large ‘traditional’ families into more homogeneous but smaller ones. Attempts
to place all genera in appropriate families have not been completely successful, but
such problems as still exist will probably be solved eventually by modern methods of
research.

For the last hundred years or so, the term ordo (‘order’) has been used for the
rank above family in the hierarchical classification. Traditionally, orders have been
given scant attention in floras. In other taxonomic literature, however, there has been
an upsurge of interest in the arrangement of families and higher ranks within the
Flowering Plants. Among the systems proposed more recently, there is an increasing
similarity in the concepts of these taxa. As a result, orders may eventually take over
the role of memory pegs from families.

The next major taxonomic category above order is that of classis (‘class’). The
question which group of taxa constitutes a class could be expected to be a subject of
much controversy. In the Flowering Plants, however, there is a remarkable and long-
standing agreement among botanists to recognise only two classes, sometimes
regarded as subclasses, viz. Liliopsida (= Monocotyledoneae) and Magnoliopsida
(= Dicotyledoneae). Flowering Plants as a whole, previously also known as Angio-
spermae, or Anthophyta s. str., are ranked sometimes as a subdivisio (Ehrendorfer,
1971), but more usually as a divisio (‘division’), for which the modern name Magno/-
fophyta has been introduced (Cronquist et al., 1966). This taxon in turn may be placed
in subregnum Embryobionta (Cronquist et al., 1966), the next higher category, which is
perhaps more widely known under the older name Cormophyta. Finally, the ultimate
rank of regnum (‘kingdom’) traditionally accommodates all plants (Vegetabilia or
Plantae s. lat.) as opposed to animals (Animalia).

The primary division of all organisms into plants and animals, as reflected in the
traditional partitioning of biology into botany and zoology, is no longer regarded as
satisfactory from a theoretical point of view. There appears to be a more fundamental
difference between those organisms that lack a distinct cellular nucleus (Prokaryota)
and those that do possess such an organelle (Eukaryota). The former group includes
only the Schizophyta or Bacteria and Blue-Green Algae (=kingdom Monera, Raven
et al., 1981). Modern authors prefer to divide the eukaryote organisms into a number
of kingdoms or subkingdoms, some accommodating those traditionally regarded as
plants. The Protista s. lat. (=Protobionta or Thallophyta) may include the auto-
trophic Algae (= Phycophyta) as well as the heterotrophic Fungi (= Mycophyta). On
the other hand, both Protista s. str. and (higher) Fungi may be treated as equivalent

System of classification

taxa (kingdoms, Raven et al., 1981), possibly of the same rank as the Embryobionta,
or plants in the narrow sense. Apart from the Magnoliophyta, the Embryobionta
accommodates the following divisions (after Cronquist et al., 1966): Bryophyta
(Mosses and Liverworts), Psilophyta (Whisk Ferns), Lycopodiophyta (=Lycophyta
or Clubmosses), Equisetophyta (=Sphenophyta or Horsetails), Polypodiophyta
(=Pterophyta or Ferns) and Pinophytina (= Gymnospermae). Traditionally, Mag—
noliophyta and Pinophyta have been treated together as Spermatophyta (= Phan—
erogamae or Seed Plants), whereas Embryobionta, excluding Bryophyta but inclu-
ding Pteridophyta (Ferns and Fern Allies), have been grouped together as Tracheo-
phyta (Vascular Plants). In many floras the treatment is restricted to the Magnolio—
phyta or Spermatophyta. The Pteridophyta are often included in smaller floras of
temperate regions, but otherwise are usually treated, like Bryophyta and Protobionta,
in independent and specialised works. It is intended that the Flora of Australia will
ultimately cover all plants known to grow naturally in the region except the Bacteria.

To illustrate what has been discussed in the preceding paragraphs, the hierarchy
of taxonomic terms is presented in Table 3 with appropriate names at each rank for
Acacia pycnantha Benth. From the family level downwards it is customary to pro—
vide the name of the original author(s) (‘authority’), often in an abbreviated form,
after the taxonomic name. These are often useful, particularly as different authors
have sometimes used the same name inadvertently for different taxa at the same
level, either as independently coined names (‘homonyms’) or as a result of misinter—
pretation (‘misapplied names’). A name in brackets indicates an earlier author who
may have used the same taxonomic name at a different rank in the hierarchy. In the
case of an infra-generic name, the author may have used the second or third element
of that name originally in combination with the name of another genus or species
respectively.

The background of phylogenetic classification

When de Jussieu proposed a natural system for the classification of plants in his
Genera Plantarum (1789), he probably did so as a true representative of the so-called
‘idealistic morphologists’. It is unlikely that he considered the distinguishing charac—
ters of the respective groups of plants to be the result of an evolutionary process, as
such hypotheses hardly entered scientific thought until the end of the 18th Century.
Contemporary biologists saw it as their task to recognise the essential (or ‘arche—
typal’) characters of taxa, thought to be obscured in Nature by a multitude of vari—
ants. In their opinion a natural system of classification of all creatures, should reflect
the ‘Grand Design’ (in a theological or philosophical sense) fundamental to Nature.
The first theory to challenge the idea of immutability of species with some success
was proposed by the Parisian professor Jean Monnet de Lamarck in his Philosophie
Zoologique (1809). It was Charles Darwin’s On the Origin of Species by Means of
Natural Selection (1859), however, that profoundly changed biological and philoso—,
phical thinking. Natural systems acquired a new dimension through evolutionary
theories, and were increasingly regarded as models reflecting degrees of actual rela—
tionship through common descent. Species within a single genus were considered to
have diverged from each other later and/or more slowly (and therefore to a lesser
degree) than genera within a family. The same principle was believed to apply to
other taxonomic ranks. A stepped hierarchical system cannot, however, adequately
reflect all stages of gradual diversification at any one time. Therefore a decision to
recognise a particular group as a distinct taxon at a particular rank will always be
somewhat arbitrary. In certain groups, taxa at the specific level may be clearly iso—
lated from each other by discontinuities in character variation, whereas relevant taxa

Table 3. Hierarchy of taxonomic categories: major ones in capitals, the most com—
monly used intermediate ones in lower case. The example shows the classification of
the Golden Wattle. Names from subregnum down to divisio after Cronquist et al.
(1966), from classis to familia after Cronquist (1981). The name for the subseries was
not validly published as Bentham did not assign it to a particular rank at any time.

REGNUM (kingdom) Eukaryota (Organisms of nucleate cells)
Subregnum Embryobionta (Stem Plants)
DIVISIO (division) Magnoliophyta (Flowering Plants)
Subdivisio
CLASSIS (class) Magnoliopsida (Dicotyledons)
Subclassis Rosidae
ORDO (order) Fabales (Leguminous Plants)
Subordo
FAMILIA (family) Mimosaceae R.Br. (1814)
Subfamilia
Tribus (tribe) Acacieae (Reichb.) Endl. (1841)
Subtribus
GENUS Acacia Miller (1754)
Subgenus Acacia subg. Heterophyllum Vassal (1972)
Sectio (section) Acacia sect. Phyllodineae DC. (1825)
Series Acacia ser. Uninerves Benth. (1864)
Subseries [Acacia ‘Racemosae’ Benth. (1842, 1864)]
SPECIES (kind) Acacia pycnantha Benth. (1842)
Subspecies
VARIETAS (variety) Acacia pycnantha Benth. var. pycnantha

(1864)

System of classification

of higher rank may be difficult to segregate and circumscribe. On the other hand cer-
tain genera may be easy to define and agree upon, but their subdivision into species
may be difficult because relevant natural populations show overlapping ranges of
variation in a number of characters. Such difficulties may well appear in floras
through keys to identification that do not always give satisfactory results.

Darwin’s ideas undoubtedly had an impact on the natural system of plant
classification developed by George Bentham and Joseph Hooker. Published in their
Genera Plantarum (1862-1883), this system was most influential until the beginning
of the 20th Century. It is interesting to note that the only comprehensive flora yet
completed for the Australian region as a whole, Bentham’s Flora Australiensis (1863—
1878), was one of the first great floras written in that period.

From the beginning of the 20th Century onwards, genetic research has provided a
deeper insight into the nature of morphologically-based taxa, particularly at generic
and subordinate levels. It has become clear that it is of limited use to recognise for—
mal categories, such as subvarieties, forms and even subforms, as was fashionable in
some ‘schools’ until quite recently. On the other hand, varieties and higher taxa,
originally only recognised because of apparent similarities of of the constituent indi—
viduals (‘phenotypes’), were usually shown to have a common genetic potential (‘gene
pool’). Encouraged by these results, botanists have attempted to provide definitions
for the lower taxa, in particular the species, by using more objective criteria, e.g. the
degree of fertility between individuals or populations. They have, however, failed to
find any criteria that are suitable for universal application and it seems as yet
impossible to remove subjectivity from taxonomic practice.

Theories on the evolution of life, as well as developments in other biological dis—
ciplines, have certainly influenced the thinking of taxonomists. Most plant taxa, how—
ever, are still recognised and defined primarily by gross morphological characters
(‘alpha taxonomy’). It is possible nowadays to test similarities and discontinuities by
using additional criteria derived from such disciplines as anatomy, palynology,
embryology, cytology, phytochemistry and genetics (‘omega taxonomy’). Taxonomists
usually take into account significant results from these areas of research when cir—
cumscribing taxa and designing systems of classification. If all taxonomic studies were
made on such a comprehensive scale, however, it would slow down a more balanced
accumulation of taxonomic knowledge over the widest possible front. A com—
prehensive system of classification even in a rather preliminary stage, is of more
immediate use for urgently needed floras.

Natural and phylogenetic systems of classification

The question remains whether ‘natural systems’ can ever be improved to the point
where they reflect adequately the course of the evolution of organisms (‘phylogeny’).
The following factors act counter to any attempts to achieve this aim:

(1) Inadequacy of the fossil plant record A\though the fossil record is relatively good”
for some categories of organisms—mostly animal groups such as molluscs and verte-—
brates—it is rather poor for others, particularly many plant groups. Consequently,
direct evidence for the pathways of evolution is largely lacking in a group like the
Flowering Plants and may never become available. Assumptions about past develop—
ment must therefore be based mainly on evidence derived from living representatives.
Unfortunately, some botanists have been tempted to present ‘genealogical trees’ in
which all the key positions of the branching system are occupied by recent taxa. Such
systems should be regarded as pseudo-phylogenetic. If one adopts the model of a
phylogenetic tree, it is only justifiable to regard it as buried by the sands of time, with
the living species just visible as extremities of the finest twigs (Fig. 22).

System of classification

(2) Convergent evolution If evolution were a process of continuing divergence only,
one could expect to approach the phylogenetic ideal gradually by simply improving
the traditional systems based on degrees of similarity. It is evident, however, that
widely different groups can become more similar through convergent evolution, at
least in a number of characters which may be conspicuous. To return to the imagery
used above: it is probable that adjacent branch tips are more recent offshoots of a
single larger branch than of those that are further apart. This assumption may not be
confirmed, however, once the sand is removed, since twigs of different branches may
have grown towards each other and may have become closer than twigs of any single
branch developing either divergently or in parallel. Convergent developments have
certainly caused misinterpretations in the past: e.g. the Magnoliopsida (Dicotyledons)
with fused corolla lobes were formerly united as the subclass Sympetalae but are now
regarded as a rather artificial group of families and orders of disparate origins. In
other words, certain taxa have reached a similar stage in their evolution with regard
to a few correlated characters, although they need not be considered by other criteria
as closely related. To overcome the problem of classifying such artificial, often poly—
phyletic taxa (‘grades’), numerical methods have been developed that enable us to
assess as many similarities and dissimilarities as possible. When making such assess—
ments, it is important to determine as far as possible which characters are ‘primitive’
and which are ‘advanced’, as only the latter can give positive indications of relative
distances of relationships. The (re-)evaluation of taxa on this wider basis results in
groups with a high probability of being monophyletic (‘clades’). This approach
appears to affect traditional systems more drastically at the higher levels where a
greater degree of uncertainty has always existed.

In conclusion, it appears that the most improved ‘natural system’ of classification
also provides the most probable model of actual evolution that can be deduced. One
cannot clearly distinguish between ‘natural’ and ‘phylogenetic’ systems. A schematic
presentation of a modern phylogenetic system of classification of the Magnoliophyta
by the Swedish taxonomist Rolf Dahlgren (1980) is reproduced in Figure 22. In this
diagram, the ‘tips of the branches’ have been grouped into larger units (orders and
superorders) by cladistic methods. Their relative proximity is an expression of simi-—
larity or dissimilarity in a range of characters.

The system used in the Flora of Australia

As explained above, the nomenclature of plants itself imposes on Floras a systematic
grouping from the generic level down, but a particular system is usually adopted for
the placement of genera into families. The choice of a system does not necessarily
determine the sequence of genera and families, since these may be arranged alpha-—
betically or according to assumed relationships at any or all of these levels. A se—
quence according to degrees of similarity appears preferable, particularly in works
which deal with many representatives of any one taxon. Taxonomic relationships
would be best expressed in a multi-dimensional scheme, whereas the treatment in a
book necessarily follows a more arbitrary linear sequence. In practice this does not
appear to be a major disadvantage, while it could also be argued that any systematic
arrangement of taxa in a Flora is primarily an expediency, theoretical considerations
being of little interest to most users. Nevertheless, it would appear undesirable to
choose a system that is clearly out of date.

The Editorial Committee for the Flora of Australia decided in 1979 that a se-
quential system should be adopted, so that the families could be assigned to particular
volumes from the beginning. For the Flowering Plants their choice fell on the latest
version of Arthur Cronquist’s system then being prepared for publication (Cronquist,

System of classification

1981), since it was thought that it would be the most modern published by the time
the first volumes of the Flora were to appear. Cronquist’s system, as relevant to
Australia, is given on the front endpapers of this introductory volume, together with a
schedule for the Flora. A systematic arrangement of taxa other than Magnoliophyta
will be decided at a later date.

Current systems of Magnoliophyta

For readers interested in the latest developments in this field, a comparison is pre—
sented here of the most recent systems of classification designed to accommodate the
whole of the subdivision Magnoliophyta. Such a discussion must be limited in scope
in this introductory chapter. It is not warranted to compare systems that are of his—
torical interest only and that have been discussed at length in other publications. As a
starting point, the latest edition of Volume 2 of A. Engler’s Syllabus der Pflanzen-
familien (Melchior, 1964) has been chosen. This work surveyed the more important
systems from 1940 onwards, down to the level of order, and provided a compre-
hensive bibliography of relevant literature.

A comparison of modern classification systems of Magnoliophyta was published
more recently in tabular form by Kenneth M. Becker (1973). Choosing Arthur Cron-
quist’s systematic sequence (1968) as a basis he made a concordance down to family
level of the systems of Armen Takhtajan (1966, 1968), Robert Thorne (1968), Hans
Melchior (1964) and John Hutchinson (1959, 1969) together with the historically
interesting one by George Bentham and Joseph D. Hooker (1862-1883). He also
accounted for the additional families accepted by H. K. Airy Shaw (1966). A slightly
modified version of Hutchinson’s system has since been published posthumously
(1973), while Takhtajan (1980) has also brought out a revised version. Both Cronquist
and Thorne have prepared updated editions of their systems, and Dahlgren recently
proposed a new system that has already appeared in two editions (1975, 1980).

The families of Flowering Plants after H. K. Airy Shaw

From its seventh edition onwards, H. K. Airy Shaw has revised J. C. Willis’s A
Dictionary of the Flowering Plants and Ferns (7th edn, 1966; 8th edn, 1973). He as—
signed most genera of the relevant taxa (including Gymnosperms!) to a family. Airy
Shaw listed and described a relatively high number of segregate families and usually
indicated relationships at that level as understood by him. He did not present an
original system, however, as the families were consistently correlated with the higher
categories of the now rather obsolete system of Adolf Engler in Sy/labus der Pflan-
zentamilien (7th edn, 1912).

Airy Shaw recognised 247 families of Flowering Plants that are known to be rep-
resented in Australia by indigenous species. Of these, 26 families (10.5%) were not
recognised as such by Melchior (1964), Hutchinson (1973) or Cronquist (1981),
including Bambusaceae and Ternstroemiaceae, which he regarded as of uncertain
status. A further 24 families (9.7%) have been accepted by only one other of these
authors and 16 (6.5%) by two of them. All 66 ‘controversial’ families are listed in the
first column of Table 4, adjusted to the left-hand margin. Their taxonomic positions—
as far as their Australian representatives are concerned—according to the other three
authors are listed in parallel columns, with alternative positions indicated by indented
names.

Compared with the systems of Dahlgren (1980), Takhtajan (1980) and Thorne
(1981) (Table 8), 18 of the 26 families (7.3% of the total) were still recognised only
by Airy Shaw. The other eight families were accepted by those three as follows:
Limoniaceae, Sambucaceae, Tetracarpaeaceae, Thunbergiaceae (by Dahlgren),

dRoplorsul|quigq —oroovsieddey
aevoordie.0aR|q
dvoplolo1yy—oraoeulsel0g
deal YyWeuy—orooeuonsay
orooriueydskq
aeaploneuog—orooriplfAys

dRodBIUOSPIARG
aead0powAD—ovaoe[ayouez
dRaploNIsNnNy—orooeRjNajOauod
avaplolsoj—oeRdde1qISUIZ

araoRruodsojys05
deIploOWos|j—orddRIeddey

aeaoeuryeqoshiyD
avd ploylURO|YD—oORIdRUIGIO A
dRodRUIWIWIOD
aevaplolurd|esaey—orsouruin say
deoployy—ovooripironuy

DRIPlOIONeG—ORIVTRAJIXES
deaploruoyouer]g—oedoepiyiAda]
ovoplosnquieg —orourwielyH
dROPlOlUUdIIAW—oRd.BUIgII A
avoployeUuLodsosayi y—ovdaov1uUojy)
aroplolueinby—oroorarjawfy |
avoiseisody—orooepiysO
dBILYeBUYy—oRooRUOlsay
orooepr| ABU
avaploywwsaasoay—orooeuissA JA
aeddIeIS—oraoRUIsRquIN] g

(F961 A01suy,) ONPI “H

(jJavaoeescjog
avaoedivoo0oR|y
aeooRUlse10g
SBIIBUOIISI Y
(j)9vaoe1podousyy
aeaoRneuog

dBoRIUOSPIARG
aeoovaD0poWAD
aeooRInosna
ae0R1soD
(j)ovoorx1g
avoonieddey
deooRuRRqosAiyD
DBIIRUIGIO A
DROIBUT[IUIWOD
dRaoriuldjesor)
(g)ova0epuldes
(avayjoyosig )—orsoniqioydny
(j)avaoe1uounD
aeooRpiyyAso7
avaoRog
dRddRUAGIOA,
DROORILIUOJY
avoovarjauAy |
dRa.ePIYIIO
aRaoRUONsay
(javaoety
aeooRulssA|y
oeaoRulsEquin| |

(1861) isinbuosy *y

aeaorieddey
(jjavsoetry,

“Ry, deodRNOIYy
aeaoRuorsay

aevaoriueydsiq

deoorneuog
(avadeyluROlYyD 9as)
(j)oeaoe1uounD
oRooR[syouez

aeaoRinosna
avaoRIOqISUIZ

avaoRUllodsojys05

“URIOH, dRadRWOID
(j)avsoRsoy

"YON svIdRYyIURO|YD

dRdoR BUIDUOTIRD

“Ig “y avooriuidjesara

dRooRIpieoRuy
aeooriqioydng

oroonioneg

arooRuo sue
avasnquieg—orooRog
aRadRUDQGIOA,
ROORILUIUOJY

‘Ig “y ovooRruepinby

aun} g seaoeIseisody
aRaoRUONSoYy

aeaoepl|AreWy

aun] g sBddR BIDIISOV
(40} pajunodoe 0u)

(€L61) wosuiyoynyy “f¢

weys Ally (xeg) ovaoeisurquiq

‘Dd ses0RdRD09R|F

Ad|pury oeooenaiyy

MBYS Ally 2 JO[1IND aeIdea]OD018poq

xeq seoorrurydsiq

[Bisoq oRadRNRUuog

‘Boyt “wou * deadEpi{Aysessiq,

asueg ovooriuospiarq

1ojAe] "Ni dRadRa90poulKD

‘wouNG seIdeINIsND

IBYBN 9RadRISOD

uoyour[g deadeuiadsojyooa

meys Ally (xeg) avaoRrwioa]D

Ig “Yy oRaoRuRjeqoshiyD
(,aea0epl]Alsesoig , 99s)

uoYdIg deadBBWUIIUOLIeD
avoploluldjesoey—ovsouunsoq

Meys Airy aroorAieooseydaig

meys Alny (31y pony) avaoeyoyosig

Ag|pury deaoeioneg

tydjopny ovaoruoueg

(qnp ‘1ejs) wyeN oeooesnquirg

"|puq ovooriuuddIAy

ig “y deooejeuadsosayly
dvoplouRinby—orsovarjawAy |

Aapury aeooviseisody

MRYS Ally w2 JoyIND seoovYyUeUy

HH YS “f oeooepr| Arey
avooeulssAW

*ZOUI] OBDORpIRIdoy

(€L61) MBYS Aary “yH

(i) parysrysry

owos ‘(Z) pationb ouos ‘soueu pajuspul Aq uMoYs ose soIwey d]edo1Z9s JO suOIIsod d1WOUOXeR] dANeUIOITY “INOJ [Je Aq JOUNSIP se
poepsesoi Jou jnq ‘sioyIne inoj Aq pastusoda1 se eIRSNY Ul SNOUdSIPUI exe} OATEIUDSIdOI YIM S]JUR[g BULOMO]] JO Sole] “p IIqQUT,

aesonquies—ovooriojiude
aBopisso]sidjes—oraoeurjos
aedu0]9TOWUIe]Og —ORIIBUOJOTOWILIOg
oeo]0udllg—orooepiioRdy
ovo1je]0g —ovoovlues07]
dBIIUOPISOg—oBddeUO]ISOWIRIOg
oeoploselinzny—orooerl|l']
DBIULATY—oORaIBINR[OIAY
deoploselinzny—oeooell]
dvaplooo|diiag—aerooepeidaposy
avoopiodig
oeapiodA N—oewyeg
dRoplouoguinja N—ovaoeoeyduid Ny
aeajoneN—orooriqny
aeaoRUlsn|jOW
dvoOplosowly—orsourwingoy]
avIPIO] ADIWI9 JAY —ORIORILUIOISLIIJAY
avoploljaqo]—oraoejnueduiey
anaoielg—oroorulsequin|
dvdplO}BYOUWI-] —oRa0RWOING
ae20R800]
aeoploryoXuoseg—oevaoel|AydoAsed
oeaonyluRrosjeaD
aeoorprxoddy
avaplooiodAY—orsayninyo
aeapioj A1os01pAY—orsaj1/OQuUI)
dean} | —ovaoepidajoiuag
oeooroieso0ddipy
dvIp1oO10g9][9 H—oRd9R|NOUNURY
({)oBd9 RIE] 99e] J
ovapiodivs01AQ—oevooRIpuBuloy
deoplolouUNnH—ovaoEseRIO[e HY
DROplOIsJOpUl]-jJ —ovdIeINY
deaploge.j—orsoullunsa]
IBIPLOIUO]|BISyY—OBvddIVSRIJIXRS
avaplouASOUIdIA—ovadeSRIJIXES

avoouojludey
avaoRuRlosg
avaoriddny
avoorpuoedy
aRooRIULSOT
aeaoRIUOpIsog
DBIIBIR|IWS
aeaodvooROlAydg
dBddBIR|IWIG
(,)o8ooepeidaposy
avaoviodig
aRooRI01y
aeodRUOquIN[aN,
oeooRiqny
DBIOBUISN|JOJ
OBddRSOUIIA)
2B99R] RWIOISEIOA)
oraoRinueduiry
aeooRUuIsequin|
aRooRIeYySOUUIT
28998997]
aeoor|Aydodiey
aevaoeuiodsoip]
(j)avsorlry
aeaorisn|[D
aeaoridy
(9261) uurWeyY seodRT[I1epAY
aeaovajeo0ddipyy
deodRjnounuey
oeoovuRnsuepy
ded9RIPURUIOY
aeooRsouuNnhH
({)aesoRIny
avooRrqe.f
(j)avaoRLIR[NSsOIH
DBIOBTRIJIXES

aeooRojlided
“"yoInyy sed RpIssoysidjes
“yoiny seaoriddny
‘yoINy eR20R1OUOLIg
aeaoele}0g
aevaoRIUOpIsog
oeoorisaiyd
ypsesy sRo0BLIOATIOg
“yoIN}Y ova BIUURUIDIOg

avaoRoo|diuag
oeaorviodig
avounueydalajAyg—oaroonoo1y
oroorarydwid Ny
aeooriqny

“yoInY seIDeUIENJOY]
“Ig “y dRadRsSOWI
DBdIBIRWUIOISE]IJA]
“Ig “Y aRoRI]OqG07]
ovooRulsequin|d
oeooRwoIng
(j)avaoetA
“Ig “yy 9899k19999]|]
aeooRuadsoipy
aeooeprxodAy
“ssnp ovaoroodAY
ovooridy
aeooepidajonusd
aeaovaiesooddiyy
JeS1IO7J] BR29810Q9]|9H
RIOBLIL|[ISE] J
aeddRIPURUIOH
oeoor(pr)se10j;ey
aeotedsng—orooriny
Aa|pury sevooeqe.y
Ag “y dBadRIUOT|eOSy
oroovuAsOuloiq

yUIT oeaodvonquies
avapissolsidjeg—oeaoeurljos

yoiny seaoriddny
ded10U0LIg—ovaoepiioedy

“URI 9eO9RI|R10g

Asj07] avaRIUOpIsOg

‘ouInG oRsoRIsalIyd
SRIULATY—oRadRINR|OIAUg
DBIOBISI|IY

“IYyoS seaovoo|dusg

“ISHIOA\ IROORIWIOIOdag

neely seooedAN

“OUNG sBIdRUOqQUINJaN

WeYUIOA, IBOORO[ONeN,
deoUIsN][OWW—ovooRvoz1y
aBIPlOSOW A] —OrsoulUINnsaT

“DC aeade[ADowWayy
aeoploljaqoJ—oeaoejnuedwe)

*ZOUI] BBIDBIUOWI]

WYARL WIR WeYOOUWIT

‘Wound 28998227
aevoploiysX{uoieg —ovaoe|Aydodied

DAPIG “L'S evaovwadsoipy]

“Ig ‘y oeooepixoddAy
aesajiiny

Japur[A} oeadR[A10D01pAHY
avaoepidajoius5D
dv9dBI1SE]ID
98910q9|[9H —ovaoR[nounuey

Meys Ally ovooeuendueyy

‘owng araordirs01hp

JOUSSIDJY ARODRIDUUNH

meus Airy (49]8uq) aeaovissopuly4
deoplouolideg—orsouruin3o]

“WOUING] BeddRIUO]|BISy

WyyBL seaovuAsowaiq

avd9R19]SO7Z—ORIDBUOIISOWILIOg
ovaAydoyjuex—ovaorescjog
avaplogsi A—ovddRYIULIOT
dBoplolulgoe A—oRvodROLA
deoploigsoquny | —ovoonyjuroy
DROIWISTY | —oRooRIUUBULIN g
aeooues1ad | —oRdoRoseG
dvoploluosesya | —ovoonoz1y
devaplooedse9Rsya | —ovaoesBljIxes
DRIPLOIWIIOIISUID | —IBIdBOY |
aeoplourLing—orooeqnoseUs
aeaiseqo[Aig—{{)ovooRnuRyeqosAlyD
avouyoh11GS—oroov1uRs0o 7]
aevoyiurl|Ayg—ovrooriqioydny
onoljasidg—orooriues07]
({)avaoetjoyinby

araorajaouayds
avaplooR|iug—oraorli]
avaplojuopouoydig—aradrisejaD
oraploineinegs—orooriplundy

(F961 Ae1suq,) JON PIN “H

2B99R191SO7
avon Aydoyluex
DBIIBISIA,
oRaoROUy
deooryluRoy
aRooRIUURULINg
aRaoRosiyed
aeaoRoziy
DRIIRTRIPIXES
aeaoRoy
SBIDBURLING
(j)ovoovurling
aeooRluRso7]
dvooviqioydny
aRooRluRdo7]
(,)ovooerjojinby
araorajs0uayds
DBOOBIRIIUS
arooRssejaD
avooRIpiuloy

(1861) sinbuosD *y

2B99R191S07
aeooryesh]Og
aeooeyqUuRl07]
ARI) 9RadRIUIONR A
deaoeylUBOy
ypiedy ‘fp aeooerwsiy
aRooRosned
aRaoRoZzly
(j)avooetuoljeosy
aeooroy
dBIIeQNOILUNS
(j)avs0Rsoy
aeaoeuysAg
avooriqioydngy
aevaoriodids
(j)ovooRtusWL |
(j)orooeninueduey
DBIOBORIIWS
aeooRjuopouoydiS
ypiesy ‘f deoorineines

(€L61) UOsuIyoINyy “¢

“Mound se99e191so7

‘dousen ovaanyAydouiurx

janbiyy aeaoRrasi A

avaoyyneg—aroorog

waysaly oraoridioquny |

aedIuISIy | —orooRluURWNg
Meys Airy (qiray) seoorjouea |

1eYBN ovaoRIUOTRIIO]
TRYBN dBoovoRdsedR IIL

Canp 11s) JaqiiA, seadRIWIO0IISUID |

‘uly oRadRURBLINS
ypiesy ‘f ovooriseqoAis
yury oeaoenuyohs
ypiesdy orooeulsejns
“ye deooRyasids

Meys Airy a uskoy “g oeadBuOWIasoUdydS

‘Oq aeadRa;D0uNydS
UDA BBIIBOR|IWIS

noipiey dvaoeJUOpouoYdiS
oRoInRINeS—ovooRIpIUNoy

(€L61) MtvYS Aaly “MH

(1u09) p 21981

System of classification

Ecdeiocoleaceae, Stylobasiaceae (by Takhtajan), Emblingiaceae (by Dahlgren and
Takhtajan) and Sphenostemonaceae (by Dahlgren, Takhtajan and Thorne). Of the
families not accepted by any of the other six authors discussed here, the following
were originally proposed by Airy Shaw: Anarthriaceae, Bischofiaceae, Blepharocary—
aceae, Flindersiaceae and Tetramelaceae.

Five of Airy Shaw’s ‘controversial’ families were described by him and his collab—
orators as new taxa, whereas another five were raised by him to this rank for the first
time. The remaining 56 families had been proposed before, some early in the 19th
Century, but generally have not been accepted at that level. However, it is clear from
the list of alternative taxa accepted by Melchior (Table 4) that most of these have
been treated at some time as subfamilies or tribes. In the eighth edition of Willis’
Dictionary, Airy Shaw included for the first time four families recently described,
viz. Aegialitidaceae, Idiospermaceae, Limoniaceae and Sphenostemonaceae, whereas
Petermanniaceae, accepted in the seventh edition, was relegated to Philesiaceae.

Table 4 is of wider interest because all four systems compared therein are rela—
tively well-known through handbooks. Hutchinson is the only one who agreed with
Airy Shaw in accepting the following eight families: Barringtoniaceae, Cartonemat—
aceae, Chloanthaceae (‘Dicrastylidaceae’), Cleomaceae, Periplocaceae, Potaliaceae,
Spigeliaceae and Strychnaceae. Of the others accepted by Airy Shaw, Xanthophyll-
aceae has been supported as a distinct family only by Cronquist, /diospermaceae by
Hutchinson and Cronquist, Dysphaniaceae by Melchior and Hutchinson, and
Sphenocleaceae by Melchior and Cronquist. Other families in the Table such as
Hanguanaceae, that would appear to fall into any of these categories, were in fact
supported by Dahlgren, Takhtajan and/or Thorne. On the other hand, Airy Shaw did
not accept two families recognised by Melchior, Hutchinson and Cronquist, viz.
Hippocrateaceae (which he referred to Celastraceae, as did Dahlgren, Thorne and
Takhtajan) and Molluginaceae referred by him to Alzoaceae, (supported only by
Thorne). Finally, it is noteworthy that Airy Shaw agreed with Melchior (as well as
Thorne and Takhtajan) in maintaining Fabaceae s. lat. (= Leguminosae) as a single
family, whereas Hutchinson and Cronquist (as well as Dahlgren) recognised Caesa/—
piniaceae and Mimosaceae next to Fabaceae s. str. as families in their own right.

J. Hutchinson’s system

The first edition of John Hutchinson’s The Families of Flowering Plants arranged
according to a new system based on their probable phylogeny (1926, 1934) was un—
orthodox in many respects. The ultimate format of his system was reached in the
second edition (1959), being only slightly updated in the posthumous third edition
(1973). Although the author certainly considered contemporary developments in
phylogenetic literature, his system can no longer be regarded as ‘modern’ as he relied
largely on a personal, intuitive approach. His conclusions have not attracted many
followers, but there is no doubt that his publications have done much to. stimulate
others. a

Hutchinson ranked the Flowering Plants as a ‘phylum’, a term not acceptable
under the Jnternational Code of Botanical Nomenclature, normally regarded as syn—
onymous with Divisio. The Dicotyledones and Monocotyledones were classed as
‘subphyla’ and were subdivided into five ‘divisions’, the latter groups perhaps compar-—
able with the subclasses of other authors. Within the Monocotyledones he recog-
nised: (1) Calyciferae, with distinct whorls of sepaloid and petaloid tepals (many
aquatic plants), (2) Corolliferae, with petaloid tepals only, and (3) Glumiflorae, with-
out coloured tepals (‘grass-like’ plants). Most subsequent authors have regarded this
subdivision as too artificial, but Hutchinson’s ideas on the lower ranking taxa have

System of classification

usually been received more sympathetically. In some more recent systems (Dahlgren,
1980; Takhtajan, 1980) an even more radical treatment has been advocated for some
of the ‘corolliferous’ orders through recognition of more segregate families.

Hutchinson’s system has been criticised for the concepts of his ‘divisions’ in the
Dicotyledons, viz. (1) Lignosae, covering the predominantly woody families, and (2)
Herbaceae, containing the non-woody ones. Such a subdivision was promoted by
some of Linnaeus’ predecessors (e.g. Robert Morison, 1620-1683), but not again for
at least two centuries. Modern authors regard this grouping as highly artificial, resul—
ting in phylogenetically improbable ‘grades’ rather than scientifically desirable
‘clades’. Hutchinson’s approach resulted in wide separation of families and orders
such as Magnoliales and Ran(uncul)ales, which are usually considered closely rela—
ted. In some instances he split traditional orders, regarded as quite natural entities by
others, enabling him to allocate relevant families to his two ‘divisions’. Further exam—
ples of such pairs of woody versus non-woody taxa are: Capparales/ Brassicales,
Myrsinales/ Primulales, Cunontales/ Saxifragales, Myrtales/ Onagrales, Araliales/
Umbellales (Apiales, s. str.), Verbenales/ Boraginales and Rubiales/ Gentianales.
Nineteen other segregate orders are unique, as far as Australia is concerned, to his
system. Hutchinson also used more traditionally formed names for the following
orders: Graminales (= Poales), Guttiferales (= Clusiales), Leguminales (= Fabales),
Palmales (= Arecales), Personales (=Scrophulariales s. str.). Of his world-wide total
of 111 orders of Flowering Plants, 99 are represented in Australia by native taxa:
many more than have been recognised in the other systems discussed here (Table 4).

According to the latest version of Hutchinson’s system the number of families of
Flowering Plants with indigenous representatives in Australia is 230. Like Airy Shaw,
he accepted quite a number of mostly small, segregate families (Table 4), but between
his 44 ‘controversial’ ones (19.1% of his total) and Airy Shaw’s 66 there were only 26
in common. Of these only eight families have not been accepted by any of the other
five authors discussed above. Another eight families were recognised exclusively by
Hutchinson, viz. Aquilariaceae, Helleboraceae, Illecebraceae, Petiveriaceae, Prionot—
aceae, Salpiglossidaceae, Saurauiaceae and Vacciniaceae, while five families are sup—
ported only by Dahlgren, viz. Aegicerataceae, Hypericaceae, Lobeliaceae, Peter-
manniaceae and Thismiaceae. Of the five or six families proposed by himself, only
Ruppiaceae was supported by Airy Shaw as well as by Cronquist and Takhtajan,
whereas Molluginaceae was recognised by all except Airy Shaw and Thorne.

Five families, represented in Australia by segregates according to Airy Shaw’s
concepts, should themselves be listed as indigenous following Hutchinson’s system,
viz. Butomaceae (in lieu of Limnocharitaceae), Caprifoliaceae (in lieu of Sambuc—
aceae), Cornaceae (for Corokia), Datiscaceae (in lieu of Tetramelaceae) and The-
aceae (in lieu of Ternstroemiaceae). Six families have either been segregated since
the second edition of his Families or replace larger ones as far as Australia is concer—
ned: /diospermaceae (1973, in lieu of Calycanthaceae), Dysphaniaceae (1973, next
to Chenopodiaceae), Barringtoniaceae (1969, in lieu of Lecythidaceae), Cleomaceae
(1969, away from Capparidaceae), Prionotaceae (1969, between Epacridaceae and
Ericaceae) and Salpiglossidaceae (1969, near Solanaceae). Unfortunately, in 1973 he
accepted Airy Shaw’s replacement of the name Chloanthaceae by the illegitimate
Dicrastylidaceae.

Hutchinson remained unique among modern authors in not recognising Chryso-—
balanaceae (in Rosaceae), Davidsoniaceae (in Cunoniaceae) and Elaeocarpaceae (in
Tiliaceae), whereas he subsequently received support for including Leeaceae in Vit-
aceae (from Dahlgren and Thorne) and Sphenocleaceae in Campanulaceae (from
Dahlgren, Thorne, and recently Takhtajan). Remarkable placings were Sphenostemon

System of classification

in T7rimeniaceae, rather than the traditional Aguifoliaceae or the modern Spheno—
stemonaceae, and Tetracarpaea in Escalloniaceae (recently also by Takhtajan) rather
than Saxifragaceae (Melchior, Cronquist, Thorne) or Tetracarpaeaceae (Airy Shaw,
Dahlgren). The relatively recent Aegialitidaceae was not accounted for by Hutchin—
son, either directly or indirectly. Finally, Emb/ingiaceae was not mentioned in the
various editions of the Families, but was placed under Capparaceae in his The
Genera of Flowering Plants (Vol. 2, 1967) as well as, ambiguously, under Flacourt—
jaceae in his later Evolution and Phylogeny (1969).

A. Engler’s ‘Syllabus’

Adolf Engler’s Syllabus der Pflanzenfamilien first appeared in 1892, under a dif-
ferent title (Engler, 1892). The system presented in this work had probably succeeded
that by Bentham and Hooker as the most influential by the turn of the century.
Engler updated his ideas in nine subsequent editions up to 1924, after 1912 with the
assistance of Ernst Gilg. An eleventh edition, edited by Engler’s successor Ludwig
Diels, was published in 1936. The twelfth edition was thoroughly rewritten and
appeared in two volumes, the first edited by Hans Melchior and Erich Werdermann
(1954), the second only by Melchior (1964). This version was quite modern in that it
took into account many contemporary ideas on phylogeny. Furthermore, the system
presented was actually a team effort by several staff members of the Berlin herbarium
rather than one man’s synthesis. It may be regarded as conservative, however, rather
than radical, even for the time of its publication. The second volume dealt only with
the Flowering Plants (Angiospermae) which were ranked as a division (‘Abteilung’).
Of the two classes recognised, Dicotyledoneae and Monocotyledoneae, only the
former was subdivided into two subclasses, viz. Archichlamideae (incl. Apetalae &
Choripetalae) and Sympetalae (Metachlamydeae). These two subclasses have been
regarded by more recent authors as artificial, polyphyletic taxa (‘grades’).

The Englerian system has been most influential at order level. A total of 62
orders was recognised world-wide, and of these 52 have indigenous representatives in
Australia, a relatively low number (Table 5). Of the Australian orders 19 were further
divided into 53 suborders, making a total of 86 suborders and undivided orders,
which approaches Hutchinson’s number of 99 more closely. Apart from maintaining
relatively large concepts at the rank of order, Engler’s system also preserved some
traditional names discarded by subsequent authors, viz. Centrospermae (+ Caryophyll-
ales), Guttiferales (+ Dilleniales & Theales), Myrtiflorae (Myrtales s. lat., incl. Hal-
oragales, Lecythidales, Rhizophorales), Tubiflorae (+ Callitrichales, Lamiales,
Scrophulariales & Solanales), Umbelliflorae (+ Apiales, Araliales and Cornales),
Helobieae, Alismatales, Hydrocharitales & Najadales), Liltflorae (Liliales s. lat.),
Microspermae (Orchidales s. lat.), Principes (Arecales), Scitamineae (Zingiberales),
Spathiflorae (Arales). Two of these, Myrtiflorae and Liltiflorae, have been reintro—
duced more recently for taxa of a higher rank, viz. superorders (Thorne, 1968 etc.;
Dahlgren, 1980). Other large, heterogeneous orders in the Englerian system were
Geraniales, Rosales, Rutales and Commelinales, whereas Sarraceniales and Papaver—
ales have been replaced, as far as their Australian representatives are concerned, by
Nepenthales and Capparales according to most subsequent authors.

According to Melchior’s edition of the Sy//abus, the total number of families of
flowering plants indigenous in Australia was 200. Family concepts have been kept
relatively large, so that many of Airy Shaw’s and Hutchinson’s segregate families
have been recognised only as subfamilies or tribes. Of the 85 ‘controversial’ smaller
families in Table 4, Melchior accepted only 11 at that rank, and none of these could
be regarded as highly controversial at the time. Dysphaniaceae, Hippocrateaceae and
Sphenocleaceae were not recognised as distinct families by Dahlgren, Takhtajan or

System of classification

Thorne, Hypoxidaceae by Takhtajan or Thorne, and Leeaceae by Dahlgren or
Thorne. As can be seen from the Table, Cronquist also rejected two of these families,
as well as Amaryllidaceae (also by Thorne) and Cochlospermaceae (also by
Takhtajan).

If Melchior’s larger concepts are accepted, the following families should be regar—
ded as indigenous in Australia instead of the segregates accepted by Airy Shaw and
Hutchinson: Ca/ycanthaceae (in lieu of Idiospermaceae), Lecythidaceae (in lieu of
Barringtoniaceae) and Saxifragaceae (in lieu of Baueraceae, Eremosynaceae and
Escalloniaceae). Melchior agreed with Hutchinson in regarding the inclusive families
Butomaceae, Caprifoliaceae, Cornaceae, Datiscaceae and Theaceae as indigenous.

Of the seven systems discussed here, Melchior’s was unique in not recognising
either Petermanniaceae ot Philesiaceae (both in Liliaceae-Luzuriagoideae), as well as
Posidoniaceae and Zosteraceae (both as subfamilies in Potamogetonaceae). Melchior
has been supported only by Hutchinson in rejecting Costaceae (in Zingiberaceae),
Cymodoceaceae (in Zanichelliaceae), Gunneraceae (in Haloragaceae), Nelumbon-
aceae (in Nymphaeaceae) and Viscaceae (in Loranthaceae). The endemic genus
Stylobasium was placed, somewhat unusually, in Chrysobalanaceae (cf. Rosaceae
after Hutchinson) rather than the mono-generic Stylobasiaceae (Airy Shaw, Takh-
tajan), Surianaceae (Cronquist), or Sapindaceae (Dahlgren, Thorne).

Table 5. The number of families and higher taxa of Magnoliophyta with indigenous
representatives in Australia according to seven recent authors.

Thorne Melchior Cronquist Takhtajan Dahlgren Hutchinson AiryShaw
(1981) (1964) (1981) (1980) (1980) (1973) (1973)

Classes 1 2 2 2 1 2
(‘subphyla’)
Subclasses
(+ undivided
classes) 2 2 (1) 11 10 2 5
(‘divisions’)
Superorders 26 _ _— 27 30 —
Orders 51 52 69 74 84 99
Suborders
(+ undivided
orders) 53 (33) $3 (33) — 55 (50) — —

Families 190 200 215 219 234 230 247

System of classification

A. Cronquist’s system

The first version of Arthur Cronquist’s system (1957) was restricted to the
Dicotyledons, but an extended treatment later appeared as a book entitled The
Evolution and Classification of Flowering Plants (1968). As stated above, the 1981
edition of his system has been chosen as the framework for the Flora of Australia.
Although original in some respects, the system is mostly a synthesis and is somewhat
conservative in its treatment of controversial groups such as the Liliales s. lat. He
acknowledges both Engler’s Syllabus and the ideas of Walter Zimmermann (1892-
1980) and Armen Takhtajan as a basis for the development of his ideas.

Cronquist treats the Flowering Plants as Divisio Magnoliophyta, with two tradi—
tional classes under the modern names Magnoliopsida and Liliopsida. He has, how—
ever, abandoned the Englerian subclasses completely, adopting instead a break-down
into eleven subclasses not unlike that of Takhtajan’s system. In the Magnoliopsida he
recognises: (1) Magnoliidae, (2) Hamamelidae, (3) Caryophyllidae, (4) Dillentidae,
(5) Rosidae, (6) Asteridae (one less than Takhtajan). The Lilfopsida are subdivided
into: (1) Alismatidae, (2) Arecidae, (3) Commelinidae, (4) Zingiberidae and (5) Lil-
jidae (two more than Takhtajan, 1980). All these subclasses embrace so-called primi—
tive as well as advanced orders and are presented as probable phylogenetic alliances
(‘clades’). Unlike Takhtajan and other modern authors such as Dahlgren and Thorne,
Cronquist does not use the taxon ‘superorder’.

According to Cronquist’s latest system, the Flowering Plants are represented in
Australia by 69 indigenous orders, an average number compared with other systems
(Table 5). Three orders are recognised only by Cronquist, viz. Callitrichales, Lecy—
thidales and Linales, and seven others have been supported by only one other author
(Table 6). The traditional order Plantaginales has not been upheld by other modern
authors such as Dahlgren; Takhtajan and Thorne. Cronquist has a relatively narrow
concept of some orders, e.g. Gentianales (excl. Rubiales and Menyanthaceae), Ger-
aniales (excl. Linales and Zygophyllaceae s. lat.) and Commelinales (excl. Restion—
ales). Relatively large concepts are maintained for the Rosales (incl. Cunoniales,
Saxifragales and Pittosporales p.p.), Sapindales (incl. Rutales and Zygophyllaceae),
Scrophulariales (incl. Bignoniales and Oleales), Violales (incl. Cucurbitales,
Passiflorales, Tamaricales and Cochlospermaceae), Cyperales (incl. Poales), Liliales
(incl. Smilacales and several segregate orders of Hutchinson and Dahlgren), Najad-
ales (incl. Zosterales) and Orchidales (incl. Burmanniales). In the 1981 edition of his
system, he has replaced Araliales by Apiales and Polemoniales by Solanales,
whereas 5 new orders have been added: Callitrichales, Hydatellales, Laurales, Nep-
enthales and Rhizophorales.

The position of the following families according to Cronquist’s system is unusual:
Austrobaileyaceae (in Magnoliales rather than Laurales), Balanopaceae (in Fagales
rather than Balanopales), Balanophoraceae (in Santalales rather than Balanophor—
ales), Boraginaceae (in Lamiales rather than Boraginales) Dichapetalaceae (in 4
Celastrales rather than Euphorbiales), Droseraceae (in Nepenthales), Elaeagnaceae
(in Proteales rather than Rhamnales or Elaeagnales), Gyrostemonaceae (in Batales),
Nelumbonaceae (in Nymphaeales rather than Ne/umbonales), Thymelaeaceae (in
Myrtales rather than Thymelaeales) and Tremandraceae (in Polygalales, like Takh—
tajan, rather than Pittosporales).

The total number of Flowering Plant families indigenous in Australia is 215
according to Cronquist’s latest system, approximately an average number (Table 5).
Of the 85 ‘controversial’ families listed in Table 4 he accepts 27: 14 in agreement
with Airy Shaw, 5 with Hutchinson and 7 with both, whereas he adds only the very
recently described Hydatellaceae. Of these 27 families, Hippocrateaceae, Idiosperm-

Table 6. An approximate concordance of subclasses (Roman numerals) and
superorders (Arabic numerals) recognised in four current systems. Similarly named
taxa in the respective systems do not necessarily cover the same orders and families
and in some cases the discrepancies are considerable. Takhtajan’s Juglandanae are
represented in Australia by introduced species only. Dahlgren’s superorder
Loasiflorae does not occur in Australia and is not listed.

Cronquist (1981) Takhtajan (1980) Thorne (1981) Dahlgren (1980)
A. MAGNOLIOPSIDA A. MAGNOLIATAE I. Annonidae 1. Magnoliidae
I. Magnoliidae I. Magnoliidae
1. Magnolianae 1. Annoniflorae p.p. 1. Magnoliiflorae
2. Rafflesianae 3. Rafflesiiflorae
3. Nymphaeanae 2. Nymphaeiflorae 2. Nymphaeiflorae
Il. Ranunculidae
4. Ranunculanae 1. Annoniflorae p.p. 3. Ranunculiflorae
Il. Hamamelidae III. Hamamelidae
5. Hamamelidanae 12. Hamamelidiflorae
(6. Juglandanae) (10. Rutiflorae p.p.)
III. Caryophyllidae 1V. Caryophyllidae
7. Caryophyllanae 5. Chenopodiiflorae 4. Caryophylliflorae
5. Polygoniflorae
8. Plumbaginanae 4. Theiflorae p.p.
IV. Dilleniidae V. Dilleniidae
9. Dillenianae 4. Theiflorae p.p. 8. Theiflorae
8. Violiflorae 7. Violiflorae

(1976: Cistiflorae)
6. Malviflorae p.p.

10. Ericanae 4. Theiflorae p.p. 9. Primuliflorae
21. Corniflorae p.p.
11. Malvanae 9. Malviflorae p.p. 6. Malviflorae p.p.
V. Rosidae VI. Rosidae
12. Rosanae 13. Rosiflorae 10. Rosiflorae p.p.

11. Podostemiflorae
12. Fabiflorae

13. Myrtanae 14. Myrtiflorae 14. Myrtiflorae
14. Rutanae 10. Rutiflorae 15. Rutiflorae
6. Geraniiflorae 15. Rutiflorae
15. Aralianae 18. Corniflorae 18. Araliiflorae
21. Corniflorae p.p.
16. Celastranae 7. Santaliflorae 16. Santaliflorae
17, Balanophoriflorae
17. Proteanae 11. Proteiflorae 13. Proteiflorae
VI. Asteridae VII. Asteridae
18. Gentiananae 15. Gentianiflorae 22. Gentianiflorae
19. Lamianae 16. Lamiiflorae 23. Lamiiflorae
17. Solaniflorae 20. Solaniflorae

20. Asteranae 19. Asteriflorae 19. Asteriflorae

Table 6 (cont.)

Cronquist (1981) Takhtajan (1980) Thorne (1981) Dahlgren (1980)
B, LILIOPSIDA B. LILIATAE Il. Liliidae II. Liliidae
VIL. Alismatidae VIL. Alism(at)idae
21. Alismatanae 22. Alismatiflorae 24. Alismatiflorae
VIII. Arecidae X. Arecidae
27. Arecanae 23. Areciflorae 30. Areciflorae
28. Aranae 24. Ariflorae 26. Ariflorae
25. Typhiflorae 27. Liliiflorae p.p.
1X. Commelinidae IX. Liliidae
24. Juncanae 26. Commeliniflorae p.p. 29. Commeliniflorae
25. Commelinanae 26. Commeliniflorae p.p. 28. Zingiberiflorae
X. Zingiberidae
26. Zingiberanae 26. Commeliniflorae p.p. 28. Zingiberiflorae
XI. Liliidae
22. Triuridanae 21. Triuridiflorae 25. Triuridiflorae
23. Lilianae 20. Liliiflorae 27. Liliiflorae p.p.

aceae, Sphenocleaceae and Xanthophyllaceae were not upheld by Dahlgren, Takh—
tajan or Thorne; Donatiaceae, Leeaceae, Limnocharitaceae and Ruppiaceae were
supported only by Takhtajan; and Caesalpiniaceae, Fabaceae s. str. and Mimosaceae
in that rank only by Dahlgren.

According to Cronquist the following families are indigenous in Australia and
should not be replaced by segregates: Bixaceae (in lieu of Cochlospermaceae, sup-
ported by Takhtajan), Grossulariaceae (in lieu of Escalloniaceae), Lecythidaceae,
Saxifragaceae (both in agreement with Melchior), Caprifoliaceae, Datiscaceae and
Theaceae (all three in agreement with Melchior and Hutchinson). Compared with his
edition of 1968, Celastraceae now includes Siphonodontaceae, but several segregate
families are additional or replace others, viz. Cabombaceae (next to Nymphaeaceae),
Caesalpiniaceae, Fabaceae s. str. and Mimosaceae (in lieu of Leguminosae), Donat—
jaceae (next to Stylidiaceae), Gyrostemonaceae (away from Phytolaccaceae), Idio—
spermaceae (in lieu of Calycanthaceae), Viscaceae (next to Loranthaceae), Cymo-
doceaceae and Posidoniaceae (next to Zosteraceae), Hanguanaceae (away from
Flagellariaceae) and Hydatellaceae (away from Centrolepidaceae).

Cronquist’s system is remarkable for not recognising Amaryllidaceae and Hypoxi-
daceae (both in Liliaceae, supported by Thorne), Cochlospermaceae (in Bixaceae,
supported by Takhtajan) and Dysphaniaceae (in Chenopodiaceae, supported by
Dahlgren, Takhtajan and Thorne). Noteworthy also is his placing of Baueraceae in
Cunoniaceae (supported by Takhtajan), Blepharocaryaceae doubtfully in Sapindaceae~
(rather than Anacardiaceae after Takhtajan and Thorne), Emblingiaceae in Polygal-
aceae (rather than Capparaceae), Escalloniaceae in Grossulariaceae and Stylobasi-
aceae in Surtanaceae.

A. Takhtajan’s ‘Outline’

Since the early 1940s Armen Takhtajan has published some 20 contributions on
the evolution and palaeogeography of plants. The majority of these, written in
Russian, are not easily followed by most English readers, but a few major ones have
appeared in other European languages. The first to be translated into English (1953)
concerned a phylogenetic system for the higher ranks of the Cormophyta, in which

System of classification

the class Angiospermae was not subdivided beyond the subclasses Dicotyledones and
Monocotyledones.

Takhtajan’s first publication to have an impact outside the U.S.S.R. was Die
Evolution der Angiospermen (1959). In that book he proposed an original grouping
of orders into superorders (13 in the Dicotyledonae, 5 in the Monocotyledonae).
Takhtajan used traditional names that had been used at the lower rank of order in the
Englerian system. His ideas subsequently developed greatly and were presented in
English under the title Flowering Plants, Origin and Dispersal (1969). In this book he
treated Magnoliatae (Dicots) and Liliatae (Monocots) as classes, dividing the former
into 7 subclasses and 15 superorders and the latter into 4 subclasses and 5 super—
orders. Besides recognising additional taxa between the ranks of class and order, he
discarded all traditional names at these levels, choosing new ones based on generic
names with standardised suffixes. This format was not changed significantly in the
most recent Outline (1980), although the number of subclasses in the Lilfatae were
reduced by one (Commelinidae into Liliidae), and eight new superorders were added
(5 in Magnoliatae and 3 in Liliatae) (Table 6). Of the new total of 28 superorders
only the Juglandanae, a relatively small one, is not represented in Australia by native
species. Takhtajan’s subclasses were very similar to those of Cronquist, particularly in
their respective systems of 1969 and 1968, a circumstance no doubt reflecting con—
sultation between them. Takhtajan’s superorders, on the other hand, probably influ-
enced the development of the systems of Thorne and Dahlgren, who may well have
provided him with some ideas in return. Takhtajan alone of these four authors used
both ranks to indicate probable phylogenetic relationships (‘clades’).

Of the 74 indigenous orders recognised by Takhtajan, 15 segregates have not been
adopted by Cronquist. Of these 15, three were unique to his system, viz. Begoniales,
Connarales and Smilacales. On the other hand, 10 orders used in Cronquist’s system
were not recognised by Takhtajan (Table 7). In comparing Takhtajan’s latest system
with his previous version (1969), it appears that four orders were discontinued, viz.
Cucurbitales, Passiflorales (both in Violales); Hydrocharitales (in Alismatales) and
Iridales (now in Liliales and Burmanniales). Apart from some minor changes in the
sequence of orders, there were five additional orders, viz. Araliales, Balanophorales;
Burmanniales, Hydatellales and Smilacales.

The following families were remarkable for their placement in Takhtajan’s system:
Actinidiaceae (in Ericales rather than Theales), Boraginaceae (in Polemoniales
rather than Lamiales), Datiscaceae (in Begontiales rather than Violales), Dichapetal-
aceae (in Euphorbiales rather than Celastrales), Frankeniaceae (in Tamaricales
rather than Violales). Some families were notable for being transferred to other
orders between the editions of 1969 and 1980: Cardiopteridaceae (from Santalales to
Celastrales), Droseraceae (from Nepenthales to Saxifragales), Emblingiaceae (from
Capparales to Sapindales), Malpighiaceae (from Geraniales to Polygalales), Nitrari-
aceae and Zygophyllaceae (from Geraniales to Rutales), Stylobasiaceae (from Rut-
ales to Sapindales); Hanguanaceae (from Restionales to Liliales).

Takhtajan recognised 16 segregate families not recognised by Cronquist (Table 7)
and no longer accepted 9 of Cronquist’s families. Further, the following families have
been synonymised by Takhtajan since 1969: Brunoniaceae (in Goodentiaceae),
Cochlospermaceae (in Bixaceae), Gyrocarpaceae (in Hernandiaceae), Hippocrat-
eaceae (in Celastraceae), Hypericaceae (in Clusiaceae), Lobeliaceae (in Campanul-
aceae), Saurauriaceae (in Actinidiaceae), Sparganiaceae (in Typhaceae), Sphenocle—
aceae (in Campanulaceae), Tetracarpaeaceae (in Escalloniaceae), Tetragoniaceae (in
Aizoaceae). Finally, Takhtajan agreed with Cronquist in the recent acceptance of
Viscaceae as a family distict from Loranthaceae.

System of classification

R. F. Thorne’s ‘Synopsis’

Robert F. Thorne kindly allowed the use of the latest version of his system (1981) so
that it could be discussed in this introductory chapter. He has written a number of
earlier papers on relationships within certain groups of Flowering Plants as well as on
general evolutionary problems. Thorne has published two papers on a phylogenetic clas—
sification of the angiosperms: the first was a synopsis with a brief introduction (1968),
the second a much more elaborate treatment (1976). Thorne considers modern phyto—
chemical research to be an important addition to morphological knowledge. His system
is original in several respects, but there is a superficial resemblance to Melchior’s
‘conservative’ one, as it does not follow the general trend of fragmentation of orders and
families. He uses the ranks of suborder and subfamily to indicate distinction as well as
close relationships between taxa. Thorne admits that his ideas are subject to constant
change, which may explain why he has not yet published them more extensively.
Although his system has great merit, its very instability renders it less suitable as a basis
for a medium- to long-term project such as the Flora of Australia.

Thorne regards the Angiospermae (or ‘Annonopsida’) as a class, and conse-
quently he treats the Dicotyledoneae (‘Annonidae’) and Monocotyledoneae (¢Lil-
idae’) as subclasses, which are immediately subdivided into 19 and 7 superorders res—
pectively. The 26 superorders are comparable to those of Takhtajan and Dahlgren
(Table 5). In Thorne’s 1976 system the respective figures were 16 (without Nymph-
aeiflorae, Proteiflorae and Solaniflorae) and 5 (without Triuridiflorae and Typhi-
florae). His earlier Cistiflorae has been renamed Violiflorae in 1981. Superorders in
the various editions do not necessarily cover the same orders and families and some—
times there are considerable discrepancies. Changes have also been made in the linear
sequence, reflecting the development of Thorne’s ideas about probable phylogenetic
pathways and the relationships of subordinate taxa. The most recent sequence is
indicated by numbers in Table 6. Thorne has presented his system not only in a
linear sequence, but also in a two-dimensional diagram as a present-day cross-section
through an imaginary phylogenetic ‘tree’, showing the presumed relationships of taxa
down to the level of order.

Of the orders recognised by Thorne, 51 are represented in Australia by native
species. This is the lowest number for all seven authors discussed here and only about
half that of Hutchinson (Table 5). It is, however, only slightly less than that of
Melchior and, like the latter, Thorne emphasises the rank of suborder. He recognises
a total of 86 suborders and undivided orders indigenous in the region, comparable
with the numbers of orders in Dahlgren and Takhtajan. The following of Cronquist’s
orders are ranked by Thorne as suborders: Aristolochiales, Laurales, Piperales (in
Annonales), Dilleniales, Lecythidales, Nepenthales (in Theales), Fabales, Sapindales
(in Rutales), Haloragales, Rhizophorales (in Cornales), Linales, Polygalales (in Ger-
aniales), Plumbaginales (in Primulales); Eriocaulales, Juncales (in Commelinales),
and Orchidales (in Liliales). Some of Cronquist’s smaller orders are accepted by~
Thorne only at family level, viz. Batales (in Rutales), Callitrichales (in Lamiales),
Plantaginales (in Bignoniales), Podostemales (in Rosales), Rubiales (in Gentianales);
Cyperales, Restionales (in Commelinales), Hydatellales (familia incertae sedis) and
Hydrocharitales (in Alismatales). By contrast, seven orders are recognised by Thorne
(and others) but not by Cronquist (Table 7). Three of these have been recognised
recently, viz. Balanophorales, Boraginales and Nelumbonales, whereas Oleales has
been transferred from Santaliflorae to Gentianiflorae. Unusual names are Annonales
(for Magnoliales s. lat.), Berberidales (for Ranunculales), Bignoniales (for Scrophu-
Jariales s. lat.) and Chenopodiales (for Caryophyllales).

soyeuuenses
sajeipodousys =
sojereddey
sajejnuedues
soyetweq]
SOB] Busy
So[erty
sojeinddes
sa[eulselog
SO]RA[R IA)
Je] ’S soyeiuousig
JE] °S sajeplaqiog
SO|RIOLA
sayeiny
soyesoydourjeg
sojeiodsontg
so]Bioisy
SOpBIET
soyeuouuy
sopRooly
soyelesy
soyery
$9]B191S07
soyeurnuan
soyeleiy
(aeounjouseyy
*Joul) sojeuouuYy
Sopet[tT
Spee]
SO[BIBLUISTTY
Spe

(1861) ausoyy,

so]eulienses
aeuodsolusg =
sapeioardeg =
sayejnueduies>
se1Oyiqny
2e1Qo]9H
SPOUT]
sayeiearded
sesoyiqny
SO[BOLA
aeloyiqn y
so]ejnounuey
SO|PBIOLA
sojeleg
sojesoydourjeg
soyedoureg
soyeynurduey
SBION NLT
SOPBIYSO]OISUY
sodiouug =
dvIOY[IquiA =
avioyiyieds =
seolqo|aH
sopeuRlquan
oeBLOY [Aqui y)

sojeouseyy
SPLOT]
SeIOY NLT
2BIQO|SH
SRIOU UT]

(p961) 201A

sajeuliensed
saye[|AydoAsep
sajeieddea
sajejnuedues
sapeyouy[eD
SO[BIBUISITY
()s9]ep1yo19
sajeieddea
(j)sojeruey
SO|RIOLA,
sajetepnydoiog
soyejnounury
S2]RJOLA
soyeqeg
(j)sayeuRs
(j)sojesey
sojeiaisy
Soyetr]
SOTPIYDO/OSHY
sopRoo1y
sayeidy
sojely
sojepelen
sajeuRnuan
sojeidy

soyeljouseyy
Soyeity
So]PUT
so[eleUsiy
Soyer]

(1861) 3sinbuosy

saypulensea
saye||Aydodiea
sojereddea
sayejnueduies
soyeiwiey]
SoyeIeUIsI]
sojeluuewing
sojereddea
(j)soye1uowajog
SO|RIOLA
sajeleynydoisg
sayeynounuey
soyeuosog
sajepuides
saye1oydourjeg
sojedouryeg
soeldisy
SO[PNET
SO[BIYSOO SL
sajRoo1y
soyeleiy
soyeiy
sojepelen
sojeuRnusy
sayelely

soyerouseyy
Soyetl]
(j)sayeoryiws
sopeieusiyy
SOpRUT]

(0861) uvleyyyey

sojeulenses
sajet|Aydofea
sajeieddey
sayejnuedues;
sapere]
so]eleusiyy
sayeluuBUIng
sojeiedded
sayeulse10g
Sojealeyy
sayeuenydoiss
soyejnounuey
SO|P[OIA
(j)sojeseddea
sayeroydourjeg
sojedourjeg
sopelaisy
())sojesesedsy
SOPBIYIO/OISLY
sajRoo1y
soyerpery
soyely
sayeiueyooipAy
soyeurnuoy
sayelesy

soyeuouuy
()sa[eseiedsy
(j)soyedeiedsy

So[eieUusiTy
soyeseiedsy

(O861) Uas8[Yyeq

sayeurenses
saye||Aydofuea
sajereddesy
sajeueduies
so]BiseuO
soyewoing
soyeiuueuing
So] BOISSRIg
sayeulsel0g
sayexig
sayeiuousig
sayeploqiag
sayeiqinons
sajeipodousyD
soyelues
sajepisdourjeg
So]R1d1sy
SORT]
sayeryoojolsuy
soyewyeg =
soeleiy
sopely
sajeuojasouody
sojeuXsody
saeyoquil = (sajeidy)

soyeuouuy,
sojepy[Areury
soyeplowdo0s[y
so[eleUsipy
sojearsy

(£261) uosuryoynyy

(i) parysiyYysiy swWos ‘soueu poquopul Aq pareoiput 18 souo 1991]

(Ajjensn) ur siops0 oye8o18as 10) suonisod saneusoipy “eRAsNY UL siUe[g SUIMOL] JO siops0 [12 JO ysl] yeonaqeydye uy *z afquy,

sajeou |.
sojeuouuy
sojeluiey]
SOTBUI[OWILUOD
$9[B19]SOZ
SoyeET
soyRIBUIsITy
(qnp ‘1e1s)
aevaonljorepAY
sojeplpowewepy
soyeuloy
SOPeUET
so]BuloD
sojejnuedues
so[elurlay,
So[BUBT]UIH
sojese
soyRIny
soyeiqioydngy
So|PUI]OWLWOD
so|eouy
soypuUeYyy
sojeusqy
so|esoy
soyrorsdiq
SoyPq ET]
sajeou
SoPBUI[OWIWOD
sajesoy
SO|BJOLA,
soeusoy
soyeiny
Sa|RUI]OWIWOD
sayeou

Vel ’s soyeipodousyy

sayesysejap

aBI1OYLIA
sopelpouseyy
ae1OYIGn |,
soyeounr
aeIgo]aH
SBIOUULT
aeiqojaH

So] BUT[OWIUOD
sajesoy
aRIOYIIA
SBIO TT
av1OYUAA
soyeynuedwed
sopelurloy
sojeuenusy
sojesey
So]BsOY
sa[elursoyH
SO] BUI[OUILUOD
so|eoug
sajearjawAy |
sopeuogy
Sa|BIUIIVIIES
sojeoesdiq
SeIOU UT]
sapesajnyny
sajeiodA5
sajesoy
soyeuqinon5
aeRO [IQuiA,
Sa[esoy
sojeuljawmwod

We] °S sayesrayiny

aeuiiadsoiua5
sayesysejaD

sayepiyiAoa7]
soyeiney]
so[eluie’]
sojeounr
soyepele nN,
SORE
sayeiseysoipAy

sopeyjarepAH
SoTeploweWe py
soyeseiojey
SoPBttT
(j)sojese10je yy
soyejnuedues
soperurloy
soyeurnuay
sojesey
sojeqe.]
soyeiqioydngy
soyeyneooug
so[Boly
(j)sayeaolg
soyeusqy
(j)sayeyjuodan
sojeorsdiq
Coy |
So[BIusT td
sapesadAa
sayesoy
So]B[OlA
sopRuloy
sajepuides
SO]BUIJIUIWIOD
sayeoy
saye||Aydodsed
SA]BIISBIID,

sae Ay
so[einey]
So[eIWiey
sojeounr
sojepelen
So] Bt
So[RIBUISITYy

soye|jaepAy
sojeprowewmepy
(j)sayeuAW
soyerry
(j)soyesesjrxes
sojejnuedues
SoyRIuRlaD
soyeurnuay
saese.y
sajeqry
soyeiqioydny
sojeyneoouy
sojeouq
sopeusear|q
sopeuogy
SO]|RSCIJIXES
soyeoesdiq
SO[BIR[IWS
soyetusy [iq
sayeiadAD
SOpRSBIJIXES
S2|B]OLA,
sa[Bulod
sojpeseuuod
sojeurjaumwoy
sopeoy
sayey|Aydodres
SO]BIISE[ID

so[eoy |
so[einey
sopeiuey
sajeounr
$9|B191SOZ
Soper]
sojequeysoipAy

soqeyjarepAyH
So[eplowewe py
sajese1oje}
sa]eIOpOWae YY
soyerouuny
sae1uspooH
sojelueioy
soyeurnuay
sojesey
soyeqe
soyeiqioydny
sapeneoog
soyRouq
sojeuseoe|y
sojeusqy
sayel9soig
sa]BuloD
sajyeo10osoiq
Sopelusi [id
sayeiadA>
soje1uound
S2|BJO1A,
sopeulod
sojeputdes
SoPRUIJOUIWIOD
sojeay y
sayey|Aydodued
SO]BIISE]ID

sayeqAyy
sojeiney]
So]BIWIe]
sajeounr
sojeurseoune
s]@P it]

soyewoing

sojeoune
SOP OWeUe YY
so|e1seuO
sa]eIOpOWae
sojeiseuQ
sojeluspoonH
So|BIURIID
soyeurnuan
sojese4
saypeuruin3aq =
soyeiqioydngy
soye[neoouy
sayeouq
so]PuUeYy y
soyeuoqy
SO]BIUIIBIIES
Sopelely
$a] BO109SOIC]
So]Btuot Iq
sopesadAD
sayeruouny,
sayeuqinony
sopelesy
So]etusi (tq
So]BUIJSUIWWOD
sajesajyyINH = (sayeisn|D)
sayeipodouayD
SO[PIISE]ID

SO]RUI[SUIWIOD
sajeuoddjog
sajRiuRlon
sajeurjos
sajesoy
sajeulaWWwo0D
soye[Nulig
soyeluousig
soyerodsonig
sojRuouuy
So] BUL[IUILUOD
SOTBIOIA
sojeurpurg
Soper]
sopeAyy
S2|R910
sojpyeues
soyray yp,
sojronyduik yy
soyroy |
sayRuOquINjaN
sojepeley
sopeq Ay;
sayeynwiig
sojeiny
SORA

SO|RIUBIID,

soyeuouuy

sayeurnuay

soperuniay
SOpeL ET

(1861) ausoyy,

SION]
sojeuos jog
soyeiny
de10YIQn |
so]RUId]sopog
so[RUIWeID =
sajeulsequin|
sojeurselurld
Sa]Rsoy
saesodig
SUIOUUTL
BOTEIDT A
sojpuepueg
aeuUodsoldyy =
aR A
S2|2I1O
so]ejeques
sajeiayniny
sajepnounury
sajeiuadeiies
sajejnounuey
‘feu ‘dd oeiqojay=
aVIOYNIAW =
soypeynwiig
sojeiny
SO|RA[RIA

sojeiny

sape1ouseyy
sajeurnuan
sojriuBsan

SBsOyN I=

(P961) AOIYDPTW

SSEt ET
sapeuosA]og
sajeyesAjog
SOTBURIOS
sojeulaisopog
(j)soyesadd5
sa]eulsequin|
soyeulseiurid
sojesoy
saeiadig
SOE]
SO[RIOLA
sojpuepueg
SITBPIYIIO
sope1Ay
(j)soyeuejnydosag
sajepRyUuRS
soyeay y,
sajronydwkny
sayeyjuadany
soypanyduAn
sojepeleny
saye1Ay
soye[nwig
(j)sajepuides
SopBalRyy

sayejed jog
So[eOuseA

sojeuriuay
so|Pury
SOENNT

(1861) 3sinbuosD

SO]RNNT
sajeuoshjog
sayeyeskjog
so]BluoWa[og
sayeulalsopog
so[Bog
sojeursequin|g
sajeuejnydoiog
SOBSRAJIXES
sayeiadig
Solerity
S2]R[OLA
sojpurpueg
SoTBPIYIO
saye1Ay
S2|B210
sojeye]ues
sajeoy]
sajeonydud yy
sayeyiluodony
sayBuoquinjaN
sojepelen
sopelAyy
soyeynwig
soyeingy
SOTBATR|

sayeyesAjog
soyeljouse yy

sojeuenuay

So]PIURIIDH
SalBeiey

(O861) uefeyyEL

sajeapojuog
sajeuosdjog
sayeyesAjog
So]BUuR]OS
sajeuaisopog
s3]B0qg
sojeuisequin|g
sajeueynydoisg
sayesodsonig
sajeiodig
soyespt[Aud
Sope[OlA
sojeurpurg
SaTeplyr1O
soyeudyy
$9|22|9
soyepeiues
sayeoy
soyrovyduiAn
soyeoy
sa/BUOqUIN|ON
$9[B19]SO7
sopeAy
sayeynwuig
sajriny
SO|BARA

soyeyesAjog
soelouseyy

sajeuenusy

so[RIURIODH
SOpBtT]

(0861) Uoss[yeq

SORE
sajeuossjog
sajejesAjog
S2|BIUOWII]Og
sajeuaysopog
sojeulUeBIH =
sojeynuig
sojeuisejuelg
sayeiodsoig
sajeiodig
so|e1opouaey
SI RIOYISSEY
sajeurpueg
SOTBPIYIIO
sojeiseuQ
soyeiuedo7
Sa]RoRIO
sajRuyrQ,
sojeury
saRIyoo]Olsuy
sajeuey
sojepelen
soypewAyy
SO|BUISIAT
SOTPLSIN
SOBAIRIA
(sajeury ose
das) sapeisidjeyy
sojeouseyy
soyeiuedo7
sojersiyd|e yy
SOLENT

(€L61) wosuryoynyy

(quos) 2 a1qR 1

$9]B191SO7
so[Rsaqisulz
Sa] BUlJaWWOD
soeuloD
SO[BlOlA
So|PIWe]
soyeoniy
sayeydd |.
sajepinu yp
Sa[BA]RA
sayeiqioydngy
sayeou
So]B[OIA
so[kou
sa]BuRlOoS
po TET.
sayeiuousig =
sajesoy
sajesoy
sayeiny
sajepequrs
sajeiny
sopeuenusy
sa|esoy
sopRuloy
soeuUey y
So|BUIJOWIWOD
sajepuoqiog =
SI BISIJEY
Sa|BI01
sojejnwiud
$9|B19]S0Z

PRIGOISH.
aeoulwR og =
SO]BULJOUILIOD
sojpuey y
S2[BJOLA
aeOyiqny
soyeonin
sojeuepueg
soepunisy,
sopeayey
soyeorpawAy |
sojes9ynInyH =
S2|B[OLA,
sojeusqy
DeIOYIGN |
SORE]
‘eur ‘dd ses0yiqny =
sajesoy
SOPBIUDIBIIES
sojepuides
Saye|e1URS
soyeiny
so]BuUBNUdH
sajesoy
aB10y IA
sopRuMey y
S2]BUL]OLUILUOD
soye[nounuery
sopeipoojolsuy
S$9|BI101q
soye[Nwiig
aR1qojaH

sojepelen
sopesoqisulz”
SO}BUI[OWILUOD
sopBuWeYYy
SO|B]OLA,
SoyBIWUe]
soyeo1g
sopeydA
soyepuni
So[BAlR
(j)sopeAW
soyeou
SOTBIOLA
sojeusqy
so]BuRlOsS
SoPHUT
sojeuepnydos9g
sajesoy
sojeyluoda nN
sojepuides
soyeyeiurs
(j)sojepuides
SoTPIqny
sapesoy
sayeroydoziyy
so/BURYYy
sajeuonsoy
sajejnounury
Sa|PISAyJeY
sojeaoldg
saye[nuitg
soyepelen

sojepelen
so]e1oqisulz
So]BuljaUUo0D
sopeuweyy
So[BlOLA
soye1uey
soyeonin,
soyeydd |
sojepunis
SO|BAIRIA
sayeorowAy |
sajeay
sopeoueUwe |
sojeusqy
(j)sayeepnydoiog
SO]BORIIWS
soyelieynydosog
So] BSRIPIXES
SO|RTLIJIXES
sojepuides
sayejelues
sojeiny
sojeuRnuan
sajesoy
soe1Ay
soPuUeY Yy
So[Buolsay
sojejnounuey
So[BIso|JJey
$o]Bo101g
soyepnwig
sayepelen

$9]b191S07
Sd[BIIQISULZ
sayejneoouy
SOJPPIILA
SO|BJOLA
SOpPRIWIET]
soyeoni
sopeydA
soyepunu
SOpPRATe
sojearjawAy
soyeoy |,
SOPBOUBLUE |
(j)soyeuloy
Sa]BUR[OS
(j)sajeseredsy
sojeuiejnydososg
SO[PSELJIXES
saye1asolq
sajepuides
sayejeques
sayeiny
sayeurnuay
sayesoy
sojesoyudoziyuy
sayeuueyy
saeog
sayejnounuey
sajeisayyjey
Sa]eaqOlg
saye[nuwiuig
(j) S89] 8191807

sajeuojasouody
SO|PIOQISUITZ
sayepudy
sopBuUBYYy
S2[B[OlA
sajRuaqia A,
sajeo1y
sojeydA y
soyepuinisy
SOPBuEL
sopearjawAy
soyeou
sajeoieure |
sopra Als
SoBUuR|OS
Soe]
Sa}BUuOsI39g =
SI|VSBIJIXES
SO[BIUIIVIILS
soyepuides
soyejeqwues
sayeiny
sayeiqny
sajesoy
sayelAy
Sa|BULeY y
sojeoune
sajeuny
sajeIyoojoIsuy
$2|BI}01 4
sajeinwitig
sa,euojasowelog

System of classification

Of the taxa ranked as orders by Takhtajan, but not by Cronquist or Thorne, the
following are ranked as suborders by Thorne: Balanopales (newly in Pittosporales),
Begoniales (in Violales), Polemoniales (in Solanales), Saxifragales (in Rosales),
Tamaricales (newly in Violales); Poales (in Commelinales). Also, the following of
Takhtajan’s orders are recognised by Thorne only as families: Connara/les (newly in
Rutales, transferred from Rosales), Elaeagnales (in Rhamnales), Thymelaeales (in
Euphorbiales); Burmanniales (in Liliales) and Smilacales (as subfamily in Liliaceae).
Other changes at the level of order in Thorne’s system between 1976 and 1981 not
indicated above are the elevation of Araliales (from suborder in Cornales), Celast-—
rales (from suborder in Santalales), Typhales (from suborder in Ara/es, also as a dis—
tinct superorder), and the introduction of the new name Violales (for Cistales, Tam—
aricales and the introduced Salicales).

Thorne recognises only 190 families with indigenous species in Australia, which is
the lowest number for all systems discussed here (Table 5). As in the case of his
orders, he regards a further subdivision of his families as important. Twenty seven
families are accepted by Cronquist but not, or no longer, by Thorne (Table 8). On the
other hand, Thorne accepts three families not recognised by Cronquist, viz. Bauer—
aceae (next to Cunoniaceae, in 1981), Cochlospermaceae (next to Bixaceae, in
1981) and Sphenostemonaceae (new since 1976). Two other differences between the
systems of Thorne and Cronquist are Thorne’s placing of Blepharocaryaceae (in Ana-
cardiaceae since 1976, rather than in Sapindaceae) and Stylobasiaceae (in Sapind-
aceae since 1976, rather than Surianaceae). Changes in Thorne’s system at family
level, not mentioned above, are the relegation of Gyrocarpaceae to Hernandiaceae
(1976), the recognition of Nelumbonaceae (out of Nymphaeaceae, 1976); Costaceae
(next to Zingiberaceae, 1981), Cymodoceaceae (next to Zanichelliaceae), Hydatell-
aceae (new in 1981) and the use of the name Juncaginaceae in preference to
Scheuchzeriaceae (since 1976). Finally, Thorne agrees with Cronquist in relegating
Amaryllidaceae and Hypoxidaceae to Liliaceae.

R. M. T. Dahilgren’s system

Rolf Dahlgren’s system is the most recent of those discussed in this chapter and
in many ways the most modern. The first version appeared in 1975 followed by a
thoroughly revised one in 1980. Dahlgren’s approach is probably the most truly
‘cladistic’, since he has relied more on numerical methods and less on personal intui—
tion. He has aimed for a ‘radical’ solution, although he certainly has not entirely
broken with tradition. Groups that could be distinguished taxonomically were
ranked—probably for prominence—as orders or families rather than as subordinate
taxa, even though this often led to an otherwise regrettable inflation.

An interesting feature of Dahlgren’s system is its presentation in a two-dimen-—
sional diagram (Fig. 22), representing a contemporary cross-section through an imag-
inary phylogenetic ‘tree’. The superorders were shaped by the relative size of their
constituent orders, and relative distances were based on ratios of similarities and dis—
similarities in a number of characters. The principal diagrams of the successive edi-—
tions were also used as ‘base maps’ to demonstrate the distribution of various char—
acters throughout the Flowering Plants (e.g. sympetaly, as in Fig. 22).

Dahlgren treated Flowering Plants as a class (Magnoliopsida), divided primarily
into Dicots (Magnoltidae) and Monocots (Lil/lidae), which were ranked as subclasses
as in Thorne’s system. His next division was into 24 superorders within the Dicots
(only one, Loasiflorae, not represented in Australia) and 7 within the Monocots.
These are comparable with the equivalent numbers in Takhtajan’s and Thorne’s sys—
tems (Tables 5 and 6), although there are major differences between the circumscrip—

100

(soyjne dy} Jo uOIssttuIad Aq paonpoidai ! ‘uaI3[ ye q

Areulseull ue jo woyshs Surpouesq sy} yYsno1y} (Wuesoid 9Y}) UOT}DIS-ssoI9 rasigeeadies B se oe a clsaiiv) ou auauss0(ee
Ajasojo aq jou Aeur yoodsor sty} Ul IepIWIS exe] Jey} BuIMOYS ‘sse[o 19}}e] 9Y1 JO (JOo1oy} syed 10) ‘s10p10 ul sIOMoyy ean
JO 99U91IND90 dy} Sa]BdIPUI ZUIPeYS “WYSII oy] UO (SUOPs|AjOIIG) BpIsdolouseW pur ij9] 24] UO (suopa]4yooou0)) BpIsdolIT sasseo
ay} sojeiedas oul] UdxOIQ IY] ‘SsIopsOJodns jo siojsnjo se uMOYS ‘(s]UR[g BuOMO]4) BAYdOOUseP BY) JO SI9p10 UL ZZ at

sa tvuvddvo

S21VHIdAD

S31VNIDVHOS |
sa 1VIsuOHdNa |
\

sav
-NIDV8WNId

Sa1VINVT
9 S31VYOOVATVS

S31WHOds,

saqviuvd S3IVHSISY \ \
“NHdONIS S31VINWIud : | :
SITVNOLLS3Y.
saqvinvey a |
, . S31VONNi
noone sa1vInNvdWvo : | woNnr :
s31WN : S31VH3SIONI
S31VHOHAONVIVE : , Sa 1VNTaWWOD
S31VNYOO saqvolya 1) Sa1VIOIA | ‘Sa1VO3NV
‘ SIONS gayyatww ! f
‘}s3vNaea sa1VvolLun
Savinsovuuy' ne S31V83SOud auliie '
s31viwwoon3 saqwiuainonos ay s3qvinatia STIVHINVIDAD
S31VOINSWYWYH S32 1VYGNIGOHIONL salvinawous ,
S31VINOaVd a ee : 's3qviv3q3.nod
= SA S31VYOGOW3¥H
SIIVIVINYS PAP ENEEY smvizon3a Sra SS
SATVOILIA sa1v3HL satvunvy \ sava¥o09so1a

s31vsvo1

s3ziv
-DVHAIXYS

svi ‘@

SITVNOW31LSO00d

s71vinonoww
7 sxiwuv

S3IVIHD /
-OTO1SINV
ssqvion PIN) Yala /
$31VNO8WN13N /
S31Vvuadid /

S21VINNVI
SaIIVIVWSITV wun

S37V173LVOAH
szqvnn

s31vinu

NVILN3D

STWAVEAIOd

S31 VYOHdOZIHY

sa1vovd

TSyuOWH saTvolyans “NY19NF Sa71VINVH3D S31 INONANYH
Soo ay sa1vuaAvevd S31v3aVHaWAN Soe
saqvav4 STV Anta 's31v10avd0uL S31VLIUVHOOWOAH
SaIWNIWYSTv8 ESE
S31VLUAW ;
lou S3TWNODATOd :
ee S31VTIAHdOAYYD \ S31VGIHIYO

System of classification

tions of taxa by these three authors. In Dahlgren’s latest system, the names of the
superorders were given the suffix -florae (following Thorne, 1968, 1976) rather than
the more widely applicable -anae of his first edition (in accordance with Takhtajan,
1969, 1980). It also presented additional superorders, viz. Fabiflorae (out of Ros—
anae), Podostemoniflorae (out of Saxifraganae), Polygoniflorae (out of Plumbagin—
anae) and Triuridiflorae (out of Lilianae). Newly synonymised superorders were:
Campanulanae (in Asteriflorae), Dillenianae, Plumbaginanae p.p. and Thymelaeanae
(under the new name Malviflorae), Hamamelidanae and Saxifraganae p.p. (in Rosi-
florae), Rafflesianae (in Magnoliiflorae) and Typhanae (in Liliiflorae). The new
name Santaliflorae covered many of the subordinate taxa of the previous Ce/astranae.
Further alterations were proposed in the linear arrangement of the superorders, as
well as in the circumsciptions of several similarly named ones.

Of the 105 orders of Flowering Plants recognised by Dahlgren, 84 are represented
in Australia by native species: a relatively high number (Table 5). Some 25 of Dahl-—
gren’s indigenous orders are not recognised by Cronquist, whereas the latter recog—
nises 10 orders that were not (or no longer) adopted by Dahlgren (Table 7). Like
other authors, Dahlgren used the name Aral/iales for Cronquist’s Apia/es. Further, he
recognised eight orders for the first time in 1980, viz. Annonales, (in Magnoliiflorae),
Boraginales (in Solaniflorae), Rhizophorales (in Myrtiflorae), Vitidales (in
Santaliflorae); Hydatellales, Phylidrales, Pontederiales (all in Lilitflorae) and Zoster-
ales (in Alismatiflorae). Similarly, five orders were synonymised viz. Nepenthales (in
Theales); Centrolepidales (in Poales), Najadales (in Zosterales), Stemonales and
Taccales (both in Dioscoreales).

In the latest edition of his system (1980), Dahlgren recognised 234 families with
indigenous representatives in Australia, the second highest number of the six systems
discussed here, not far behind Airy Shaw’s total. He accepted segregate families when
there was doubt about the correct placement of the genera concerned, but changes in
the second edition make it clear that he was content to synonymise such families
once a more Satisfactory position had been found. Thirty three families were recog—
nised by Dahlgren but not by Cronquist (Table 8). Apart from the changes mentioned
above, the following families were newly recognised by Dahlgren in 1980: Coroki-
aceae (in Cornales), Sonneratiaceae (in Myrtales), Thunbergiaceae (in Scrophulari-
ales), Asteliaceae, Dasypogonaceae, Dianellaceae, Doryanthaceae nom. nud.,
Geitonoplesiaceae nom. nud., Hanguanaceae, Luzuriagaceae and Petermanniaceae
(all in Asparagales) and Hydatellaceae (in Hydatellales?). The following were
synonymised in 1980: Dysphaniaceae (in Chenopodiaceae), Gyrocarpaceae (in Her-
nandiaceae), Idiospermaceae (in Calycanthaceae), Leeaceae (in Vitaceae), Oro-
banchaceae (in Scrophulariaceae), Potaliaceae, Spigeliaceae and Strychnaceae (in
Loganiaceae), Siphonodontaceae (in Celastraceae), Sphenocleaceae (in Campanul-
aceae), Stylobasiaceae (in Sapindaceae), Xanthophyllaceae (in Commelinaceae),
Ecdeiocoleaceae (in Restionaceae) and Limnocharitaceae (in Alismataceae). Finally,
in 1980 Dahlgren introduced Hypericaceae for Clusiaceae as used in 1975.

Concluding remarks

After the preceding discussions of seven authors and six systems, the following
general remarks can be made:
1. The Flowering Plants still are subdivided primarily into Monocots and Dicots,
although modern authors appear to be increasingly dissatisfied with these two as
equivalent natural groups, the former taxon probably being regarded as the more
homogeneous (see e.g. Dahlgren, 1980).
2. The traditional further subdivisions above the level of order, based on one or a few

102

System of classification

related characters, have practically disappeared since Melchior’s (1964). An original
division into subclasses was developed by Cronquist and largely adopted by Takhtajan
(Table 6). Thorne and Dahlgren only recognise Monocots and Dicots at that rank.
Hutchinson’s comparable ‘Divisions’ have generally been rejected as being too arti-
ficial. A division into superorders has been pioneered and developed by Takhtajan,
whereas Thorne and Dahlgren have adopted similar approaches.

3. There is still a controversy between the ‘conservatives’ such as Thorne (and pre-
viously Melchior) and the ‘radicals’ such as Dahlgren (previously also Hutchinson
and Airy Shaw) about the assignment of taxa to certain ranks. The former prefers the
ranks of suborder and subfamily to indicate ‘lesser’ taxonomic differences, whereas
the latter gives greater exposure to any relevant distinctions at the major ranks of
order and family. Cronquist and Takhtajan occupy positions in the middle of this
spectrum, although the latter—in other ways slightly more ‘radical’—makes a more
consistent use of all ranks available for subdivision (Table 5).

4. Dahlgren (1975a, 1980) and Thorne (1976, 1981) have produced a superior type of
two-dimensional diagram, presented as a horizontal cross-section through an imag—
inary phylogenetic ‘tree’, to illustrate their systems of the recent Flowering Plants.
Diagrams of a traditional format, looking more or less like vertical ‘genealogical trees’
of exclusively recent taxa (e.g. Hutchinson 1973, Takhtajan 1969), are open to
misinterpretations of a pseudo-phylogenetic nature and should therefore be dis—
couraged. The latter type is only acceptable if all recent taxa are placed at the tips of
the branches, i.e. only allowing for a one-dimensional arrangement of these. It should
be remembered, however, that even a two-dimensional diagram is less than ideal as a
means to express relationships which are actually multi-dimensional in nature.
Although Dahlgren in particular has reached a new level of sophistication (Fig. 22), it
should be pointed out that some of his principles were previously applied by A. A.
Pulle (1952), whose diagram—with circles of various sizes representing orders and
some of their character-states—was reproduced by Melchior (1964).

5. A recent trend is the recognition by several authors of a greater or smaller number
of segregate families (and orders) in the Rosiflorae (and the transfer of some of these
taxa to Ara/iiflorae and Corniflorae by Dahlgren). Another tendency is the recog—
nition of an increasing number of orders and families in the Liliiflorae by Takhtajan
and particularly Dahlgren (as well as a large number of subfamilies by Thorne). Both
developments were strongly influenced by the studies of Huber (1963, 1969). Further
concepts subject to radical change are, e.g., those of Violiflorae/ Malviflorae and
Rutiflorae/ Geraniiflorae, whereas the placing of several individual orders and families
is equally not yet resolved to everyone’s satisfaction. Although there is certainly
much common ground between the four most recent authors discussed here, there are
also diverging developments in their ideas about a number of groups and a consensus,
even in general terms, is still some time off.

References

The following list provides not only more complete citation of references given in the
text, but also a selection of additional books and papers relevant to Flowering Plant
Taxonomy (asterisked *). Preference has been given to contributions of the last ten to
fifteen years, although some older but still relevant ones have been included. Pub-
lished proceedings of symposia have been listed under their general titles; some
papers have been listed individually under the relevant author.

Adanson, M. (1763), Familles des Plantes, 2 vols. Vincent, Paris. Repr. (1966), with
Introduction by F. A. Stafleu; Cramer, Lehre.

103

avaplosJopoWseY—oeaoelIq
({)avaploseunzny—oavaoeiyiq]
IVIPIOIUO]|POSY—ovaoeFeIXES
avoplouksowssq—ovaoeseljixes
({)—oeadereddea
devaplonsiyy—ovoovuisesog

avaIplOa|OIOIap9y—ovadeuONsay
aeaplouseovIG—oavaori[I]
avaploaesy—orooeliq
avaploneuog—ovooeIpl[AIS
(Qavaploaesy—oraoelry]

dea plosoysOYyUeK—aRo0EUIT
avaploinosny—orodRNAjOAuoD
avaplols1oj—orooRuURWLINg
IVIPIOIUO] [BOS —ovdoRTLIJIXES
({)avaploaequiin Ay\—orooeII]

deaoRWadsojys05

avoploluld|esaey—oroouqe.
avaploluounig—oradeluapooyH

aroonioneg

({)avaplouseoeIG—oraoelI]
aevaplojapoydsy—orooeiiq
avaploseiedsy—ovoorily
aevaplopeidajosy—oraoeukoody
avaploisejsod y—oaraoepiys1Q
devaploidy—oraorlely
()avaprojopoydsy—araoetyty
ovaploply|AeUy—oraoRII]
avaploArsy—arooei|I']
avaploulssA Ay —ovaoeulssAJAL

(1861) eus0YyL “Ay

aeddBIOPOWIR YY
DBIOBIETIIS
(j )avaoeuejnssoin
DBIOVSEIJIXES
(j)avaoRleshjog
aeaoBulselog

IVIIBUOIISAY
dRoORARSY
ovaovarsy

[B1soq sraseneuog
dBdNBIIT
aeaoRa0yOYURX
aeaoeinosng
dBIIBISIOD
DRIORSRIJIXES
aeo0RII]
avooexig
aeaoeluldjesarsy
‘Od seodR1uouNIg
aeooriuouns
aRaoRaRsy
DBIOEIIT
DBIOVI|I]
avoorpeidajosy
aeBddeplydIO,
aeooridy
aeoorI]
aeadR II]
aeooRaRsy
avaoeulsik yl

(1861) smbuosy -y

aeddeIOpOWae}y
dBddeISOIIY
JBIOBIUO] [LISA

aeaoeuAsowaiy
aBooRIsUI|qUIg

aRaoRUlse10g

meys Airy 2
JI]IND *q aeadea[OD01apIq

aeaovuaEoRrig
aeaoeylueklog
aevaoRIplAis
aeodoRIWIOYg
avaova0yOyURKX
aeaorinosng
aeadRIs10D
dvooRIUO]|eISy
aeaoRo1ysjoD
aeooRxig
avaonqey
dRaoRIUspooH
deooriuounD
deaoeuseoRIqg
aeaor[spoydsy
oeooRrdeiedsy
avaoepeidaposy
deBdDEpIyIO
aevooridy
({)aevs0R|apoydsy
deaoepr|Aewy
aeaovarsy
aeaoeulsiA

(0861) uvlexyyey “vy

‘Ig “Y aRade0powseyYy
pnu “wou deadeisa{douojiay
“WOUNG sRadRIUO]|e9Sq
WYBL sesdeuAsowssq

Meys Ally oeoorisuljquiq
Aa|pury aevooenaiyq

ava.euoNsay
*QsI|BS ovadRUaLoLIG
pnu ‘wou sea0eyiuRAI0g
aeaoeipyAis
“qsljes aeodR][ouLig
‘ound seadeuoso0dAseq
‘Wound seadeINdsND
“999g dBddRISIOD
‘plu “wou dRIIRtY¥OIOD
“Dd avsoroyajoD
uoyoue]g dvaoevwadsoyys0>5
“Ig “Y dvodeluidjesaea
aeooRIuapooH
Ad|pury desovioneg
“YOUNG seIDRIIISy
‘ssn¢ “yy aeaoejopoydsy
‘ssn “Ty ovoor8eiedsy
‘Ig ‘Yy ovaoepeidajosy
Aa|pury aeoouiseisody
Aajpury oevaovidy
ypiesy ‘¢ deoovoAYyUy
WHS “f eea9epr|Aiewy
‘|puq ovaovansy
dun] g aeIdRIBIDIITIV

(0861) wosstyeg “LAY
Gi) porysryysry

euros *(4) pationb owos ‘saweu poyuopul Aq poreorpur soyruey o3e80189s jo suomisod o1mouoxe) aaNRUIdITY “INoJ [Je Aq Jado] yey
JB JOUNSIP sB papsedai yOu Inq ‘sioYINe ino} Aq pastusooa1 se eIeLIsNy Ul snoOUdsIpUT exe} YA siULIg BULIDMO].] JO Sore] *g a[quy

deIplosoyOYyURK—oedIEII]
aeooe[es jog
deoploissoquny | —orooeyluROy
JBdPIOIWISIY |] —OvdodRIUURLUINg
aeaplosedsesela |] —ovaoeseljixes

SBIOBUBLING

avaploiseqo|Aig—oradepuides

deaoevuOWaysoudyds

dvaploajoousydS—oeaorinueduiey
ovoplolursiedg—orooevydA |,
dBoplonesauUOS—oRooRIYIAT]
aRaploae|IuS—oeadel [I]
aeaplojuopouoydis—oraoesseloD
avaploonquieg—oraourojyuded
aeo9RU0IISOUIRIOg
dRaploaesy—oerooel|I]
(g)2e8oplosernzny—orooell]
()oevoploseinzny—oerooell]
aeaploysueqoiQ—orooenejnydosog
deaplolidgQ—oradror|Q,
aRoplolesljyIN—ovsoe||Aydosh7
dBaploloJy—oea9dRI11I 7),
IRIPIOUIEN|JOWJ—ovddROZIV
aRaplosOWMJA,—orooRqe.y
avaploseunzn]—ovoorli]
aeaploljaqgo]J—orooejnuedue;
({)aeoplooneig—ovaoeulsequin|d
deaployeyoouu]—ovoorl ews y
IBIPIOII]—BdIEIIA
deoplouodsoip]—orooeyluesje;
aeaplopixodé #—oeaoer]

aeaoRisn|D
deap1oajeid0ddipy—oroonsysejaD
deaploaoysOYyIUeK—oeddBI|IT

deaoRa0yOYUeK
‘dausenp aesor|Aydoyjuex
aeooRyUuROy
avooRlUURWINg
DBIDVSLIJIXES
aeodRUuRLINS
(j)aesovuelng

()avsoeoyinby
‘Dq see0Ra[90usydSg
oeaonluRrdieds
avooRlelauUOS
DBIDBIETIWIS
aeaoRlIselaD
aeaoRojuded
avooviddny
opoovaRsy
deddRORTIWIS
DBIOBOL|IWIS
avaovyourqolO
aeooridoO
aeaoeAydosh7
DBIDVIOY

DBddBUISN [OY -

SBdORSOUIIJA
DBIORIE|IWIS
seaorinuedues
ovooeulsequinyg

aeodR]LIBYOUUIT]

9R998997]

DAPIG L'S Rooeuadsorpy
DBIORIIT

aevoorisn|D
“ssne “Jy seadeaqeisoddiyy
oeooeurnsuepy

aeooRo0yIOYURX
aevaorlesAjOg
aeaoryuROy
aeoorluURWIng
dBIORIUO]|ROST
aedoRqnoIeUIS

ypiesy “pf ovooeIseqgo[Ais

desoeuOWasousyds
aeaoejnuedues
aeaoeydA
JBIIENLIOUUOS
DBIOBIETIWS
“piey, deodejuopouoydis
({)ovaoR1ojlidea
yoIny seooriddny
avooRIWoUg
aevoorisaliud
aeooeisaiud
“JUIA BRIdBYIURQOIO
avaonridoQ
DBIOBUBIIIN,
aBd0R10W
aeaoRUISN||OW
oeaoRgey
aedoeISoIIUd
aeaorjnueduies
aeooeulsequinig
“WYYRL Ieooe WeYyoouWTT]
“young 98998907]
oeaoeyluRoAyea
aeooepixodAyY

aeaoeisniD
dBIddE1ISEIID.
aeooruensuepy

‘ound sevsdR20YIOYIUeX
aeooryedh]Og
woysal] seooeIsoquny |
ypiesy ‘f aeooriusiy |
TWYBN seodeoed1e9RIII |
‘uly oeaoRuRLINS
deaoepuides
Meys Airy 2 uskoy “g
aeaoeuOWasousyds
aeooR[nuedwues;
1ydjopny oeaoev1uesieds
SID 3 [suq aeaoenesouuog
‘WUdA DBIdIIRTIWIS
dBINEIISE[ID
YUIT deo9RONqUIeS
aesdRU0IsOWIOg
ypiesy if ovsoew0Yd
“OWN sBddRISOTIY
YON] 9vdORIUURLIOIOg
aeaoRuEyNnydol9s
uojajeA dedRTIdO
Aa|pury] aesoeuesiNn
Yur] ovadR10jy
YON seadeUIsN| OW
Ig “Yy oBaorsoulyy
eBisoq dvaoRselinzn 7
“Ig “y de99R1]9q07]
“ZOUI] OBIBIUOWIT
avdoUIBUISITY
de20R1 A,
aeooRyURoAyey
“Ig “y oeaoepixoddyy
(aevadRIsn[D “]5ut)
“ssnf “Ty avaorouadAyY
dBIdBIISEIID
Meys Ally oeadeuensuey

System of classification

*Beck, C. B. (ed.) (1976), Origin and Early Evolution of Angiosperms. Columbia
University Press, New York.

Becker, K. M. (1973), A comparison of angiosperm classification systems, Taxon 22:
19-50.

*Bendz, G. & Santesson, J. (1973), Chemistry in Botanical Classification, Nobel
Symposium 25. Academic Press, New York & London.

Bentham, G. (1863-1878), Flora Australiensis, 7 vols. Reeve, London. Repr. (1967);
Asher & Reeve, Amsterdam.

Bentham, G. & Hooker, J. D. (1862-1883), Genera Plantarum, 3 vols. Reeve,
London. Repr. (1965), with Introduction by W. T. Stearn; Cramer, Weinheim.
Brown, R. (1810-1830), Prodromus Florae Novae Hollandiae et Insulae Van-Diemen,
Vol. 1 & Suppl. 1. Taylor, London. Repr. (1960), with Introduction by W. T.

Stearn; Engelmann(Cramer), Weinheim.

*Clifford, H. T. (1963), Angiosperm hybrids in the Australian flora, Queensland
Naturalist 17: 32-34.

*Clifford, H. T. (1977), Quantitative studies of inter-relationships amongst the
Liliatae, in K. Kubitzki (ed.), Flowering plants: evolution and classification of
higher categories, P/. Syst. Evol. Suppl. 1: i-viii, 1-416.

*Clifford, H. T. & Stephenson, W. (1975), An Introduction to Numerical
Classification. Academic Press, New York.

*Corner, E. J. H. (1976), The Seeds of Dicotyledons, 2 vols. Cambridge University
Press, Cambridge.

Cronquist, A. J. (1957), Outline of a new system of families and orders of
dicotyledons, Bull. Jard. Bot. Etat 27: 13-40.

*Cronquist, A. J. (1960), The divisions and classes of plants, Bot. Rev. (Lancaster)
26: 426-482.

*Cronquist, A. J. (1965), The status of the general system of classification of
flowering plants, Ann. Missouri Bot. Gard. 52: 281-303.

Cronquist, A. J. (1968), The Evolution and Classification of Flowering Plants.
Mifflin, Boston, & Nelson, London.

*Cronquist, A. J. (1969), Broad features of the system of angiosperms, Taxon 18:
188-193.

*Cronquist, A. J. (1973), Chemical plant taxonomy: a generalist’s point of view on a
promising speciality, in G. Bendz & J. Santesson, Chemistry in Botanical
Classification, Nobel Symposium 25. Academic Press, New York & London.

*Cronquist, A. J. (1975), Some thoughts on angiosperm phylogeny and taxonomy, in
J. W. Walker, et al., The bases of angiosperm phylogeny, Ann. Missouri Bot.
Gard. 62: 515-834.

*Cronquist, A. J. (1977), On the taxonomic significance of secondary metabolites in
angiosperms, in K. Kubitzki (ed.), Flowering plants: evolution and classification
of higher categories, P/. Syst. Evol. Suppl. 1: i-viii, 1-416.

Cronquist, A. J. (1981), An Integrated System of Classification of Flowering Plants,
Columbia University Press, New York.

Cronquist, A. J., Takhtajan, A. & Zimmermann, W. (1966), On the higher taxa of
Embryobionta, Taxon 15: 129-134.

106

System of classification

Dahlgren, R. (M. T.) (1975a), A system of classification of the angiosperms to be
used to demonstrate the distribution of characters, Bot. Not. 128: 119-147.

*Dahlgren, R. (M. T.) (1975b), The distribution of characters within an angiosperm
system I: some embryological characters, Bot. Not. 128: 181-197.

*Dahlgren, R. (M. T.) (1977a), A commentary on a diagramatic presentation of the
angiosperms in relation to the distribution of character states, in K. Kubitzki
(ed.), Flowering plants: evolution and classification of higher categories, P/. Syst.
Evol. Suppl. 1: i-viii, 1-416.

*Dahlgren, R. (M. T.) (1977b), A note on the taxonomy of the ‘Sympetalae’ and
related groups, Pub/. Cairo Univ. Herb. 7/8: 83-102.

Dahlgren, R. M. T. (1980), A revised system of classification of the angiosperms,
Bot. J. Linn. Soc. 80: 91-124.

*Dahlgren, R. & Clifford, H. T. (in press), The Monocotyledons: a Comparative
Study. Academic Press, London.

Darwin, C. R. (1859), On the Origin of Species by Means of Natural Selection.
Murray, London. Repr. (1950), with Forword by C. D. Darlington; Watts,
London.

*Davis, G. L. (1966), Systematic Embryology of the Angiosperms. Wiley, New
York.

*Davis, P. H. & Heywood, V. H. (1963), Principles of Angiosperm Taxonomy.
Oliver & Boyd, Edinburgh.

*Eames, A. J. (1961), Morphology of the Angiosperms. McGraw-Hill, New York.

Ehrendorfer, F. (1971), in D. von Denffer et al., Lehrbuch der Botanik, 30th edn.

Fischer Verlag, Stuttgart. Transl. (1976), as Strassburger’s Textbook of Botany;
Longman, London.

*Ehrendorfer, F. (1977), New ideas about the early differentiation of angiosperms, in
K. Kubitzki (ed.), Flowering plants: evolution and classification of higher
categories, Pi. Syst. Evol. Suppl. 1: i-viii, 1-416.

*Ehrendorfer, F. (1978), in D. von Denffer et al., Lehrbuch der Botanik, 31st edn.
Fischer Verlag, Stuttgart.

Engler, (H. G.) A. (1892), Syllabus der Vorlesungen tiber Specielle und Medicinisch-
Pharmaceutische Botanik. Borntraeger, Berlin.

Engler, (H. G.) A., assisted by Gilg, E. (1912), Syllabus der Pflanzenfamilien, 7th
edn. Borntraeger, Berlin.

‘Engler, (H. G.) A. & Diels, L. (1936), Syllabus der Pflanzenfamilien, 1\th edn.
Borntraeger, Berlin. i

*Erdtman, G. (1966), Pollen Morphology and Plant Taxonomy, Vol. 1: Angiosperms.
Hafner, New York.

*Erdtman, G. (1969), Handbook of Palynology: Morphology, Taxonomy, Ecology.
Munksgaard, Copenhagen, & Hafner, New York.

*Gibbs, R. D. (1974), Chemotaxonomy of Flowering Plants, 4 vols. McGill-Queen’s
University Press, Montreal.

*Gornall, R. J.. Bohm, B. A. & Dahlgren R. (M. T.) (1979), The distribution of
flavenoids in the angiosperms, Bot. Not. 132: 1-30.

107

System of classification

*Green, J. R. (1909), A History of Botany 1860-1900: being a continuation of F.G.
von Sachs History of Botany, 1530-1860. Repr. (1967); Russell & Russell, New
York.

Hamann, U. (1976), ‘Hydatellaceae’ a new family of Monocotyledonae, New Zealand
J. Bot. 14: 193-196.

*Hedberg, I. (ed.) (1979), Parasites as plant taxonomists, proceedings of a symposium
held in Uppsala, 1978, Symb. Bot. Upsal. 22: 1-221.

*Hegnauer, R. (1962-1973), Chemotaxonomie der Pflanzen, 6 vols. Birkhauser
Verlag, Basel.

*Herout, V. (1973), A chemical compound as a taxonomic character, in G. Bendz &
J. Santesson, Chemistry in Botanical Classification, Nobel Symposium 25.
Academic Press, New York.

*Heywood, V. H. (ed.) (1968), Modern Methods of Plant Taxonomy, Report of a
Conference organised by the Botanical Society of the British Isles, 1967.
Academic Press, London.

*Heywood, V. H. (ed.) (1973), Taxonomy and Ecology, Proceedings of an
International Symposium held at Reading, 1972. Academic Press, London.

*Heywood, V. H. (1973b), Chemosystematics—an artificial discipline, in G. Bendz &
J. Santesson, Chemistry in Botanical Classification, Nobel Symposium 25.
Academic Press, New York & London.

*Huber, H. (1963), Die verwandtschaftsverhiltnisse der rosifloren, Mitt. Bot.
Staatssamml. Miinchen 5: 1-48.

Huber, H. (1969), Die samenmerkmale und verwandschaftsverhiltnisse der liliifloren,
Mitt. Bot. Staatssamml. Miinchen 8: 219-538.

*Huber, H. (1977), The treatment of the monocotyledons in an evolutionary system
of classification, in K. Kubitzki (ed.), Flowering plants: evolution and
classification of higher categories, P/. Syst. Evol. Suppl. 1: i-viii, 1-416.

Hutchinson, J. (1926-1934), The Families of Flowering Plants, 2 vols. Macmillan,
London.

Hutchinson, J. (1959), The Families of Flowering Plants, 2nd edn, 2 vols. Oxford
University Press, London.

Hutchinson, J. (1964-1967), The Genera of Flowering Plants (Angiospermae), 2 vols.
Oxford University Press, London.

Hutchinson, J. (1969), Evolution and Phylogeny of Flowering Plants. Academic
Press, London.

Hutchinson, J. (1973), The Families of Flowering Plants, 3rd edn. Oxford University
Press, London.

*Jeffrey, C. (1977), Botanical Nomenclature, 2nd edn. Arnold, London.

*Jensen, S. R., Nielsen, B. J. & Dahlgren, R. (M. T.) (1975), Iridoid compounds,
their occurrence and systematic importance in the angiosperms, Bot. Not. 128:
148-180.

Jussieu, A. L. de (1789), Genera Plantarum secundum Ordines Naturales Disposita.
Herissant, Paris. Repr. (1964), with Introduction by F. A. Stafleu; Cramer,
Weinheim.

108

System of classification

*Kubitzki, K. (ed.) (1977), Flowering plants: evolution and classification of higher
categories, symposium held in Hamburg, 1976, Pl. Syst. Evol. Suppl. 1: i-viii,
1-416.

Lamarck, J. B. A. P. Monnet de (1809), Philosophie Zoologique. Dentu, Paris.
Repr. (1960); Engelmann (Cramer), Weinheim.

Linnaeus, C. (1751), Philosophia Botanica. Kiesewetter, Stockholm. Repr. (1966);
Cramer, Lehre.

Linnaeus, C. (1753), Species Plantarum, 2 vols. Laurentii Salvii, Stockholm. Repr.
(1957-1959), Vol. 1 with an Introduction by W. T. Stearn; Vol. 2 with Appendix
by J. L. Heller & W. T. Stearn; Ray Society, London.

Linnaeus, C. (1754), Genera Plantarum, Sth edn. Holmiae Salvii, Stockholm. Repr.
(1960), with Notes by W. T. Stearn; Engelmann(Cramer), Weinheim.

*Mabry, T. J. (1973), The chemistry of disjunct taxa, in G. Bendz & J. Santesson,
Chemistry in Botanical Classification, Nobel Symposium 25. Academic Press,
New York & London.

*Mabry, T. J. & Behnke, H. -D. (eds) (1976), Evolution of Centrospermous families,
symposium held during the XII International Botanical Congress, Leningrad,
1975, Pl. Syst. Evol. 126: 1-106.

Mendel, G. (1866), Versuche iiber pflanzen-hybriden, Verh. Naturf. Vereins Briinn 4:
3-47. Transl. (1958), in E. W. Sinnot, L. G. Dunn & T. Dobzhansky, Principles
of Genetics, 5th edn. McGraw Hill, New York.

Melchior, H. (1964), A. Engler’s Syllabus der Pflanzenfamilien, 12th edn, Vol. 2:
Angiospermen. Borntraeger, Berlin.

Melchior, H. & Werdermann, E. (1954), A. Engler’s Syllabus der Pflanzenfamilien,
12th edn, Vol. 1: Bakterien-Gymnospermen. Borntraeger, Berlin.

*Metcalfe, C. R. (1960-1972), Anatomy of the Monocotyledons, 6 vols. Oxford
University Press, London.

*Metcalfe, C. R. & Chalk, L. (1950), Anatomy of the Dicotyledons, 2 vols. Oxford
University Press, London.

*Pankhurst, R. J. (ed.) (1975), Biological Identification with Computers, Proceedings
of a Meeting held at Cambridge, 1973. Academic Press, London.

Pulle, A. A. (1952), Compendium van de Terminologie Nomenclatuur en
Systematiek der Zaadplanten, 3rd edn. Oosthoek, Utrecht.

*Radford, A. E., Dickison, W. C., Massey, J. R & Bell, C. R. (1974), Vascular Plant
Systematics. Harper & Row, New York, Evanston.

Raven, P. H., Evart, R. F. & Curtis, H. (1981), Biology of Plants, 3rd edn. Worth
Publishers, New York.

*Sachs, (F. G. )J. von (1875), Geschichte der Botanik vom 16. Jahrhundert bis
1860. Transl. (1890), as History of Botany (1530-1860). Clarendon Press,
Oxford. Repr. (1967); Russell & Russell, New York.

Shaw, H. K. Airy (1966), A Dictionary of the Flowering Plants and Ferns by J. C.
Willis, 7th edn revised by H. K. Airy Shaw. Cambridge University Press, London.

Shaw, H. K. Airy (1973), A Dictionary of the Flowering Plants and Ferns by J. C.
Willis, 8th edn revised by H. K. Airy Shaw. Cambridge University Press, London.

109

System of classification

*Sneath, P. H. A. & Sokal, R. R. (1973), Numerical Taxonomy: the Principles and
Practice of Numerical Classification. Freeman, San Francisco.

*Solbrig, O. T. (1970), Principles and Methods of Plant Biosystematics.
Collier-Macmillan, Toronto.

*Sporne, K. R. (1976), Character correlations among angiosperms and the importance
of fossil evidence in assessing their significance, in C. B. Beck (ed.) Origin and
Early Evolution of Angiosperms. Columbia University Press, New York.

*Stafleu, F. A., et al. (eds) (1978), International Code of Botanical Nomenclature,
adopted by the XII International Botanical Congress, Leningrad, 1975. Bohn,
Scheltema & Holkema, Utrecht.

*Stearn, W. T. (1973), Botanical Latin: History, Grammar, Syntax, Terminology and
Vocabulary, 2nd edn. David & Charles, Newton Abbot.

*Stebbins, G. L. (1974), Flowering Plants: Evolution above the Species Level.
Harvard University Press, Cambridge, & Arnold, London.

*Stebbins, G. L. (1975), Deductions about transspecific evolution through
extrapolation from processes at the population and species level, in J. W. Walker
et al., The bases of angiosperm phylogeny, Ann. Missouri Bot. Gard. 62:
515-834.

*Stebbins, G. L. (1976), Seeds, seedlings and the origin of angiosperms, in C. B.Beck
(ed.) Origin and Early Evolution of Angiosperms. Columbia University Press,
New York.

*Steele, E. J. (1979), Somatic Selection and Adaptive Evolution: On the Inheritance
of Acquired Characters. Wallace, Toronto, & Croom Helm, London.

*Street, H. E. (ed.) (1978), Essays in Plant Taxonomy, dedicated to Emeritus Prof
T. G. Tutin. Academic Press, London.

*Swift, L. H. (1974), Botanical Classifications: a Comparison of Eight Systems of
Angiosperm Classification. The Shoe String Press, Hamden.

Takhtajan, A. (1953), Phylogenetic principles of the system of higher plants, Bot.
Rey. 19: 1-45; transl. from Russian in Bot. Zurn. (Leningrad) 35: 113-135(1950).

Takhtajan, A. (1959), Die Evolution der Angiospermen. Fischer Verlag, Jena.

Takhtajan, A. (1969), Flowering Plants: Origin and Dispersal. Oliver & Boyd,
Edinburgh.

*Takhtajan, A. (1973), The chemical approach to plant classification with special
reference to the higher taxa of Magnoliophyta, in G. Bendz & J. Santesson,
Chemistry in Botanical Classification, Nobel Symposium 25. Academic Press,
New York.

*Takhtajan, A. (1976), Neoteny and the origin of flowering plants, in C. B. Beck
(ed.) Origin and Early Evolution of Angiosperms. Columbia University Press,
New York.

Takhtajan, A. (1980), Outline of the classification of flowering plants (Magnol-
iophyta), Bot. Rev. 46: 225-359.

*Tétényi, P (1973), Homology and biosynthetic routes: the base in chemotaxonomy,
in G. Bendz & J. Santesson, Chemistry in Botanical Classification, Nobel
Symposium 25. Academic Press, New York.

Thorne, R. F. (1968), Synopsis of a putatively phylogenetic classification of flowering
plants, Aliso 6: 57-66.

110

System of classification

*Thorne, R. F. (1974a), A phylogenetic classification of the Annoniflorae, Aliso 8:
147-209.

*Thorne, R. F. (1974b), The ‘Amentiferae’ or Hammamelidae as an artificial group: a
summary statement, Brittonia 25: 395-405.

*Thorne, R. F. (1975), Angiosperm phylogeny and geography, in J. W. Walker
et al., The bases of angiosperm phylogeny, Ann. Missourt Bot. Gard. 62:
515-834.

Thorne, R. F. (1976), A phylogenetic classification of the Angiospermae, Evol. Byol.
9: 35-106.

*Thorne, R. F. (1977), Some realignments in the angiospermae, in K. Kubitzki (ed.),
Flowering plants: evolution and classification of higher categories, P/ Syst. Evol.
Suppl. 1: i-viii, 1-416.

Thorne, R. F. (1981), Phytochemistry and angiosperm phylogeny: a summary
statement, in D. Young & D. Seigler (eds), Phytochemistry and Angiosperm
Phylogeny. Praeger Scientific, New York.

*Valentine, D. H. (ed.) (1972), Taxonomy, Phytogeography and Evolution,
Conference held at Manchester, 1971. Academic Press, London.

*Vida, G. (ed.) (1972), Evolution in Plants, Symposium held at Tihany, Hungary,
1970. Akadémiai Kiad6, Budapest.

*Walker, J. W. (1976), Comparative pollen morphology and phylogeny of the
ranalean complex, in C. B. Beck (ed.), Origin and Early Evolution of
Angiosperms. Columbia University Press, New York.

*Walker, J. W., et al. (1975), The bases of angiosperm phylogeny, Symposium of the
American Institute of Biological Sciences, Ann. Missouri Bot. Gard. 62: 515-834.

*White, M. J. D. (1978), Modes of Speciation. Freeman, San Francisco.

*Zimmermann, W. (1959), Die Phylogenie der Pflanzen, 2nd edn. Fischer Verlag,
Stuttgart.

111

Opposite. Spring flora on a granitic slope of the Darling Scarp east of Perth, Western
Australia, with Eucalypt woodland on the skyline. Photograph — A. S. George

Overleaf. Open forest of Eucalyptus nitens (Deane & Maiden) Maiden, near Bendoc,
East Gippsland, Victoria. Photograph — R. D. Johnston

KEY TO FAMILIES OF FLOWERING PLANTS

Hi. T. Clifford

Embryo with 1 cotyledon; leaf venation usually
convergent; leaf base usually sheathing; perianth
3- (occasionally 2— or 4—) merous
(monocotyledons)

Embryo with 2 (rarely 1, 3 or more) cotyledons; leaf
venation usually reticulate; leaf base rarely
sheathing; perianth 4-5— (rarely 3— or more than
5-) merous (dicotyledons)

Dicotyledons

Flowers with at least one perianth whorl

Flowers lacking perianth

Either one or both perianth whorls fused into a cap

Perianth segments not fused into a cap

Leaves invested with peltate scales

Leaves glabrous or, if indumentum present, not of
peltate scales

Leaves gland-dotted

Leaves not gland-dotted

Leaf base sheathing

Leaf base not sheathing

Leaves exstipulate

Leaves stipulate

Tendrils present

Tendrils absent

Gynophore present; leaves usually alternate

Gynophore absent; leaves opposite

Perianth segments more than 6 (counting sepals and
petals if both present)

Perianth segments 6 or fewer (counting sepals and
petals if both present but not barks, scales or
plumes on fruit)

Corolla segments (or perianth segments) free

Corolla segments (or perianth segments) united

All or most flowers unisexual

Most flowers bisexual

Ovary superior

Ovary inferior

838

820

4
10

Himantandraceae

Myrtaceae
6

Epacridaceae
7

Eupomatiaceae
8

Vitaceae
9

Capparaceae
Eucryphiaceae

572

12
386

13
44

14
40

113

Key to families

14 Floating aquatics; leaves whorled, much divided

114

Land plants; leaves alternate, opposite, or absent
Gynoecium apocarpous

Gynoecium syncarpous or carpel 1

(1) Climbers; leaves opposite

(2) Climbers (or plants spreading over the ground);
leaves alternate

(3) Non-climbers, not spreading

Leaves gland-dotted

Leaves not gland-dotted

Leaves compound

Leaves simple or absent

Petals 4

Petals 5

Leaves gland-dotted

Leaves not gland-dotted

Stamens 3-5 in male flowers

Stamens usually 8 in male flowers

Stamens 5 in male flowers

Stamens more than 5 in male flowers

Stamens usually 8; style 1; stigma entire or lobed

Stamens 10; styles or stigmas more than 1

Ovary entire; stigmas glabrous

Ovary lobed; stigmas plumose

Leaves opposite

Leaves alternate, clustered, or absent

Flowers strictly unisexual; shrubs or trees

Flowers polygamous; trees usually with yellow sap

Climbers with tendrils

Tendrils absent

Twiners or lianes

Shrubs, trees or herbs, sometimes scrambling

Stipules absent; disc absent; petals smaller than
sepals, entire, sometimes absent

Stipules present; disc present; petals as long as or
longer than sepals, emarginate

Latex present

Latex absent

(1) Styles 3, distinct, simple or branched

(2) Style 1 with 2 or more stigmas

(3) Style and stigma 1 or stigma sessile

Ceratophyllaceae
15
16
18

Rutaceae

Menispermaceae
17

Rutaceae
Simaroubaceae
19

Rutaceae

21
Simaroubaceae
Anacardiaceae
Anacardiaceae
23
Sapindaceae
24
Anacardiaceae
Simaroubaceae
26

27
Euphorbiaceae
Clusiaceae
Passifloraceae
28

Menispermaceae

Dichapetalaceae
Euphorbiaceae
31
Euphorbiaceae
32

Male flowers with staminodes

Male flowers without staminodes

Ovary 1-locular

Ovary more than 1-locular

(1) Seeds endospermic; carpels dry, falling entire;
leaves not succulent though often thick

(2) Seeds endospermic; carpels dry, dehiscent; leaves
not succulent

(3) Seeds non-endospermic; fruit a succulent drupe;
leaves succulent

Calyx segments free

Calyx segments united or calyx minute

Ovary 1-locular

Ovary more than 1-locular

Ovary stipitate

Ovary sessile

Leaves stipulate

Leaves exstipulate

Seeds endospermic; leaves not succulent

Seeds non-endospermic; leaves succulent

(from 13)

Climber with tendrils

Non-climbers

Herbs or undershrubs

Trees

Petals 5

Petals 0, 2 or 4

Style 1

Styles two or more

(from 12)

Gynoecium apocarpous

Gynoecium syncarpous or carpel 1

Flowers perigynous

Flowers hypogynous

Leaves alternate or radical

Leaves opposite

Sepals 5; stamens indefinite

Sepals 4; stamens 4 or 8

Perianth segments indefinite; carpels indefinite

Sepals 4-5; petals 4-5; carpels 4

Stamens indefinite

Stamens 10 or fewer

Key to families

Tiliaceae
33

Flacourtiaceae
34

Malvaceae
Euphorbiaceae

Zygophyllaceae
Euphorbiaceae
36

Capparaceae

Malvaceae
Icacinaceae
Aquifoliaceae
Zygophyllaceae

Cucurbitaceae
41

Apiaceae
Haloragaceae
Hernandiaceae
Datiscaceae

719

Rosaceae
Crassulaceae
Idiospermaceae
Crassulaceae
50

115

Key to families

116

Leaves peltate
Leaves not peltate

Carpels embedded in receptacle

Carpels not embedded in receptacle

Style 1 with 3-5 stigmas

Styles (or stigmas when styles much reduced) as
many as carpels

Climbers

Non-climbers

(1) Perianth segments 10-14

(2) Sepals 3; petals 6

(3) Sepals 4-5; petals 3-5

(1) Perianth segments all petaloid; herbs

(2) Perianth segments all petaloid; shrubs or trees

(3) One or more whorls of perianth sepaloid

(1) Perianth spiral; leaves with peltate indumentum

(2) Perianth 3 + 3 + 3; indumentum, if present, not
peltate

(3) Sepals 5; petals 5; indumentum, if present, not
peltate

(1) Herbs; leaves usually much incised

(2) Trees, shrubs, or undershrubs; leaves entire to
distinctly incised

(3) Trees; leaves bipinnate

(from 49)

Style 1, stigmas 1 or more

Styles (or stigmas when styles much reduced) free
from one another, as many as there are carpels

Leaves peltate

Leaves not peltate

Leaves gland-dotted
Leaves not gland-dotted
Leaves alternate

Leaves opposite

Stigma simple

Stigmas 3 or more
Flowers 4—merous
Flowers 5—merous
Leaves compound
Leaves simple or absent
Leaves gland-dotted
Leaves not gland-dotted

51
52

Nelumbonaceae
Cabombaceae

Ochnaceae

54
55

Austrobaileyaceae
Annonaceae
Dilleniaceae

Ranunculaceae
Magnoliaceae
56

Himantandraceae
Annonaceae

Ranunculaceae

Dilleniaceae
Mimosaceae

64
Tropaeolaceae
60

Rutaceae

Ochnaceae
Simaroubaceae
Rutaceae
Malpighiaceae
65

Rutaceae
Simaroubaceae

714

715

716

719

Leaves opposite

Leaves alternate, radical, clustered, or absent

Sepals 4; petals 4
Sepals 5; petals 5

Petals sessile or with short claws; leaves fleshy

Petals with long claws; leaves not fleshy

(1) Flowers 3—merous (usually sepals 6, petals 6,

carpels 6 or 3)
(2) Flowers 4—merous
(3) Flowers 5—merous
Leaves fleshy; seeds lacking endosperm
Leaves not fleshy; seeds endospermic
Stamens united into one or more groups
Stamens free
Carpels 2
Carpels 3
Leaves not expanded at time of flowering
Leaves present at time of flowering
Leaves entire
Leaves lobed or much dissected
Carpels 5 or fewer
Carpels more than 5
Leaves fleshy
Leaves not fleshy
Carpels usually 2-3
Carpels 5
Leaves stipulate; petals white
Leaves exstipulate; petals yellow
(1) Petals 2
(2) Petals 3
(3) Petals 4
(4) Petals 5

(5) Petals more than 5, or whole perianth petaloid or

sepaloid, sometimes in 1 whorl
Leaves simple
Leaves compound
(1) Sepals 4, rarely 2-3
(2) Sepals 5
(3) Sepals 6
Ovary superior
Ovary inferior

Key to families

69
Crassulaceae
68
Crassulaceae
Malpighiaceae

Menispermaceae
70

71
Crassulaceae
Saxifragaceae
72

73
Dilleniaceae
Malpighiaceae
Anacardiaceae
74

715
Ranunculaceae
716
Ranunculaceae
Crassulaceae
17
Dilleniaceae
78
Simaroubaceae
Surianaceae
Polygalaceae
80

149

347
Polygalaceae
Caesalpiniaceae
82

141

145

126

117

Key to families

118

Leaves radical or alternate

Leaves opposite or verticillate

Style 1, with 1 or more stigmas, or stigma sessile
Styles more than 1, quite free from one another
(1) Stamens 2

(2) Stamens 3

(3) Stamens 4, alternating with petals
(4) Stamens 4, opposite petals

(5) Stamens 6

(6) Stamens 7 or 8

(7) Stamens 10 or more

Placentation basal or free-central
Placentation parietal

Leaves simple, entire or much divided
Leaves compound

Climbers with leaf-opposed tendrils
Plants without tendrils

Leaves simple or absent

Leaves compound

Herbs

Shrubs or trees

Leaves with short, pointed lobes
Leaves quite entire

(from 85)

Stamens tetradynamous; leaves simple

Stamens not tetradynamous; leaves usually compound

Stamens free

Stamens united

Leaves simple or absent
Leaves compound

Leaves entire or absent
Leaves dissected

Petals glabrous

Petals densely hairy inside
Leaves 3-foliolate or palmate
Leaves pinnate

(1) Ovules 1 in each loculus
(2) Ovules 2 in each loculus
(3) Ovules indefinite
Ovules 1 in each loculus
Ovules 2 in each loculus

104

85
Droseraceae
87
Caesalpiniaceae
88

100
Myrsinaceae
Brassicaceae
Brassicaceae
Caesalpiniaceae
Vitaceae

90
Capparaceae
Brassicaceae
91
Aquifoliaceae
Celastraceae

Brassicaceae
Capparaceae
94

Meliaceae

96
Sapindaceae
Tremandraceae
Olacaceae

99
Simaroubaceae
Burseraceae
Capparaceae’
Sapindaceae
Burseraceae

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

(from 85)

Flowers in heads or spikes; heads solitary or in
racemes

Flowers not in heads or spikes

Ovary borne on long stalk (gynophore)

Ovary sessile

Ovary 1-locular

Ovary more than 1-locular

Anthers opening by longitudinal slits

Anthers opening by terminal pores

(from 83)

Leaves large, palmately lobed

Leaves otherwise

(1) Stamens 2

(2) Stamens 4

(3) Stamens 5-8

(4) Stamens 10 or indefinite

Flowers in clusters, racemes, or panicles

Flowers solitary in leaf axils

Leaves gland-dotted

Leaves not gland-dotted

Style and stigma 1

Styles or stigmas 4

Stamens hypogynous

Stamens perigynous

Anthers opening by pores; anther-connective with
sickle-shaped appendages

Anthers opening longitudinally; connective without
appendages

Style 1

Styles 4

(from 105)

Leaves simple or absent

Leaves compound

Leaves entire, or with more than 2 lobes

Leaves 2-lobed

Leaves gland-dotted

Leaves not gland-dotted

Ovary half-inferior; margins of petals fringed with
long hairs

Ovary wholly superior; petals not fringed

Key to families

Mimosaceae
101
Capparaceae
102
Flacourtiaceae
103
Zygophyllaceae
Elaeocarpaceae

Aceraceae
105

106

107

112

123
Oleaceae
Lythraceae
108

109
Rutaceae
Cunoniaceae
111

110

Melastomataceae

Lythraceae
Celastraceae
Elatinaceae

“
113
121
114
Zygophyllaceae
Rutaceae
115

Rhizophoraceae
116

119

Key to families

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

120

Style and stigma 1

Styles or stigmas more than 1

Flowers hypogynous

Flowers perigynous

Leaves in whorls of 3-4

Leaves in pairs, opposite

Leaves with 2 or more conspicuous longitudinal veins
besides midrib

Midrib only conspicuous longitudinal vein

Leaves with revolute margins; style 1, with 3
branches

Leaf margins not revolute; styles 2 or 4

(from 112)

Stamens free

Stamens united

Leaves gland-dotted

Leaves not gland-dotted

(from 105)

Flowers hypogynous, polygamous

Flowers perigynous

Stipules absent

Stipules present

Style and stigma 1

Styles more than 1

(from 82)

Leaves gland-dotted

Leaves not gland-dotted

Stamens indefinite

Stamens 10 or fewer

Style and stigma 1

Style with 4 stigmas

Leaves alternate or radical

Leaves opposite or verticillate

Style 1, with 1 or more stigmas

Styles several, free

Aquatic herbs with alternate, rosetted floating leaves
and opposite submerged leaves

Trees, shrubs or herbs

(1) Stigma 1

(2) Stigmas 2

(3) Stigmas 4

117

120

118

119
Tremandraceae
Rutaceae

Melastomataceae
Lythraceae

Frankeniaceae
Cunoniaceae

122

Meliaceae
Rutaceae
Zygophyllaceae

124

125

Clusiaceae
Eucryphiaceae
Lythraceae
Cunoniaceae

Myrtaceae

127

128

129
Lecythidaceae
Grossulariaceae
130

135

131

134

Trapaceae
132

133
Alangiaceae
Onagraceae

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

Ovary 1-locular
Ovary 4-locular

Herbs; flowers very small

Shrubs or trees; flowers above 6 mm in diameter

Style 1, with 1 or more stigmas
Styles several, free

Petals fringed with long hairs
Petals not fringed

Stamens 4

Stamens more than 4, usually 8
Aquatic herbs

Shrubs

Leaves with 2 or more longitudinal veins besides

midrib
Midrib the only longitudinal vein
Ovary 1-locular
Ovary 4-locular
(from 81)
Ovary 1—2-locular
Ovary 3-5-locular
Ovary adnate to one side of calyx-tube
Ovary free
(1) Fruit a legume
(2) Fruit globose, indehiscent
(3) Fruit a capsule
(1) Ovary usually 3-locular
(2) Ovary 4-locular
(3) Ovary 5-locular
(from 81)
Ovary open at top, with sessile stigmas
Ovary not open at top
Herbs
Small shrubs
(from 79)
(1) Sepals 2
(2) Sepals 3
(3) Sepals 4

(4) Sepals 5 or more, or calyx cup-like with indistinct

lobes, or entire in bud

Flowers actinomorphic
Flowers zygomorphic

Key to families

Combretaceae
Onagraceae
Haloragaceae
Grossulariaceae
136
Haloragaceae
Rhizophoraceae
137

138

139

Trapaceae
Grossulariaceae

Melastomataceae
140
Melastomataceae
Onagraceae

142

144
Chrysobalanaceae
143

| Caesalpiniaceae
Xanthophyllaceae
Zygophyllaceae
Sapindaceae
Elaeocarpaceae
Meliaceae

Resedaceae
146
“

Lythraceae
Saxifragaceae

148
152
155

156

149
Caesalpiniaceae

121

Key to families

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

122

Twiners
Non-twiners

Herbs
Shrubs or trees

Stamens 5 or fewer; perianth often scarious

Stamens usually more than 5; perianth not scarious;

leaves (and often stems) fleshy
Leaves simple or absent
Leaves compound
Leaf venation palmate
Leaf venation not palmate
(1) Stamens 5
(2) Stamens 8
(3) Stamens indefinite
Stamens 8-10, free or united
Stamens indefinite, united
Ovary superior
Ovary inferior or semi-inferior
Style 1 with simple stigma, or stigma sessile
Styles or stigmas more than 1
Leaves opposite or verticillate
Leaves alternate, radical, or absent
Leaves gland-dotted
Leaves not gland-dotted
Leaves simple
Leaves compound
Flowers hypogynous
Flowers perigynous or epigynous
Leaves simple
Leaves compound

Leaves with 2 or more conspicuous longitudinal veins

besides midrib
Midrib only conspicuous longitudinal vein
Stamens 10 or fewer
Stamens indefinite
Flowers actinomorphic
Flowers zygomorphic
Flowers perigynous
Flowers not perigynous
(1) Stamens 3
(2) Stamens 5
(3) Stamens usually 10

Basellaceae
150

151
Lecythidaceae

Amaranthaceae

Portulacaceae
153
Caesalpiniaceae
Caesalpiniaceae
154
Hamamelidaceae
Polygalaceae
Lecythidaceae
Caesalpiniaceae
Lecythidaceae
157

316

158

251

159

178

160

162

161

Rutaceae
Rutaceae
Myrtaceae

163

175

Melastomataceae
164

165

173

166

171

Lythraceae

167
Hippocrateaceae
Celastraceae

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

Ovary quite superior

Ovary half-inferior

Petals with narrow, pointed lobes

Petals entire

Petals clawed; stamens unequal, usually united at
base

Petals sessile, shorter than sepals

Stamens 5, united; anthers connate round ovary

Stamens 10

Ovary 1-locular; ovules 2 or more

Ovary 2-3-locular; 1 ovule in each loculus

Flowers hypogynous

Flowers perigynous

Ovary 1-locular

Ovary 2- or more-locular

(from 162)

Stamens 5

Stamens more than 5

Stamens free

Stamens united

Ovary 1-locular

Ovary 2- or more-locular

(from 158)

(1) Stamen 1

(2) Stamens 2-4

(3) Stamens 5

(4) Stamens 6-9 (rarely 5—10)

(5) Stamens 10

(6) Stamens indefinite

Leaves deeply notched and palmately veined

Leaves quite entire and pinnately veined

Leaves simple

Leaves pinnate or bipinnate

Leaf venation well-marked and palmate

Leaf venation inconspicuous, or leaves absent

Stipules present; calyx oblique, of 5 segments; ovary

4—S-locular; fruit a capsule

Stipules absent; calyx not oblique, of 5 free sepals;
ovary 1-locular; fruit a legume

Leaves simple or absent

Leaves compound

Key to families

169
Rhizophoraceae

Rhizophoraceae
170

Malpighiaceae
Rhizophoraceae
Violaceae

172

Fabaceae
Malpighiaceae
174

Lythraceae
Mimosaceae
Elaeocarpaceae

Meliaceae

176

177

Fabaceae
Fabaceae
Zygophyllaceae

179

180

183

209

215

235
Caesalpiniaceae
Anacardiaceae

| “181
182
Caesalpiniaceae
Olacaceae

Melianthaceae

Caesalpiniaceae

184
202

123

Key to families

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

124

Leaves bifid; venation palmate
Leaves not bifid
(1) Herbs

(2) Shrubs, trees or woody climbers; flowers
actinomorphic or nearly so

(3) Small shrubs; flowers zygomorphic

(1) Twiners with milky sap

(2) Twiners; sap not milky

(3) Plants more or less erect, not twining

Flowers actinomorphic

Flowers zygomorphic

Climbers

Non-climbers, more or less erect

Twiners

Climbers with leaf-opposed tendrils

Stamens opposite petals

Stamens alternate with petals

Each stamen more or less enclosed by small
hood-shaped petal

Stamens not enclosed by petals

Leaves gland-dotted

Leaves not gland-dotted

Base of calyx covered by several imbricate sepaloid
bracteoles

Bracteoles absent or not covering base of calyx

Sepals free

Sepals united

(1) Ovary 1-2-locular

(2) Ovary 3—locular

(3) Ovary 5-locular

Ovules 1 per loculus

Ovules 2-several per loculus

Ovary 1—2-locular; ovules few to many per loculus

Ovary 1-locular; ovules 2

Ovules 1 per ovary

Ovules 2 or more per ovary

Anthers opposite petals

Anthers alternate with petals

Ovary 1-locular

Ovary 2- or more-locular

Ovary subtended by nectar-secreting disc

Ovary not subtended by nectar-secreting disc

Caesalpiniaceae
185

186

188

Violaceae
Cardiopteridaceae
Pittosporaceae
187

Byblidaceae
Violaceae

189

190

Pittosporaceae
Vitaceae

191

192

Rhamnaceae
Sterculiaceae

Rutaceae
193

Epacridaceae
194

195

198

196
Celastraceae
Grossulariaceae
Corynocarpaceae
197
Pittosporaceae
Icacinaceae

199

200

Opiliaceae
Icacinaceae
Icacinaceae

201
Celastraceae
Grossulariaceae

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

(from 183)

Climbers with leaf-opposed tendrils

Non-climbers or, if climbing, tendrils not
leaf-opposed or tendrils absent

Leaves gland-dotted

Leaves not gland-dotted

Stamens 5, staminodes 5

Stamens 5, staminodes absent

(1) Trees; leaves pinnate; ovary with 3 parietal
placentas; fruit a long 3-angled capsule

(2) Woody climbers; leaves imparipinnate; ovary with
2 collateral ovules; fruit 1-seeded

(3) Herbs; leaves 2-foliolate or pinnate; ovary with
axile placentas; fruit usually with 2 or more seeds

Stamens free

Stamens united

Ovary 1-locular; leaves bipinnate

Ovary 3-5 locular; leaves pinnate

Leaves pinnate

Leaves bi- or tripinnate

(from 178)

Stamens free

Stamens 9, united

Leaves simple

Leaves compound

Style arising from base of ovary

Style terminal

Fruit a legume

Fruit globose

Ovary 1-locular, usually with more than 2 ovules

Ovary 2— or more-locular, with | or 2 ovules per
loculus

Disc present; stamens inserted within disc

Disc absent

(from 178)

Flowers zygomorphic

Flowers actinomorphic or nearly so

Posterior petal enclosed by the remainder, or absent

Posterior petal enclosing the remainder in bud

Stamens united

Stamens free

Key to families

Vitaceae

203

Rutaceae
204

205
206

Moringaceae
Connaraceae

Zygophyllaceae
207
208

Mimosaceae
Meliaceae

Meliaceae
Vitaceae

210
Fabaceae

211
213

Rosaceae
212

Caesalpiniaceae
Xanthophyllaceae

Caesalpiniaceae

w214

Sapindaceae
Akaniaceae

216

217
Caesalpiniaceae
Fabaceae

218

222

125

Key to families

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

126

Climbers

Non-climbers

(1) Leaves simple

(2) Leaves pinnate

(3) Leaves bi- or tripinnate; ovary 5—locular

(4) Leaves bipinnate; ovary 1-locular

Staminal tube long and narrow, surrounding style
Staminal tube short, open

Ovary free; stipules persistent

Ovary adnate to one side of throat of calyx; stipules

caducous
Leaves simple or unifoliolate
Leaves compound
Leaves gland-dotted
Leaves not gland-dotted
Style inserted near base of ovary, hairy
Style terminal

Ovary and back of petals covered with scales; flowers

in heads or clusters at end of branchlets
Not as above

Flowers perigynous; ovary enclosed in hypanthium;
stamens borne on hypanthium, sometimes near

base

Not as above; flowers hypogynous

(1) Ovary usually stipitate; ovules several; sepals
united ‘

(2) Ovary sessile; ovule 1; sepals usually free

(3) Ovary sessile, 5-locular; ovules 1 per loculus;
sepals free

Leaves gland-dotted

Leaves not gland-dotted

Herbs

Shrubs or trees

(1) Leaves bipinnate

(2) Leaves pinnate; leaflets 2; venation palmate

(3) Leaves pinnate; leaflets more than 2 or, if 2,
venation pinnate

Ovary 1-locular

Ovary 2- or more-locular

(1) Stamens unequal; anthers dehiscing by pores

(2) Stamens equal; ovule |

(3) Stamens equal; ovules more than 1

Connaraceae
219

220
Meliaceae
Meliaceae

Mimosaceae

Meliaceae
221

Sterculiaceae

Chrysobalanaceae

223
228

Rutaceae
224

Simaroubaceae
225

Rutaceae
226

Lythraceae
227

Caesalpiniaceae
Anacardiaceae

Ochnaceae
Rutaceae

229
Zygophyllaceae
230
Mimosaceae
Caesalpiniaceae

231

232

233
Caesalpiniaceae
Anacardiaceae
Caesalpiniaceae

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

Ovary 1- or 3-locular, with 1 ovule (rarely 2) per
loculus

Ovary 4— or 5-locular, with 2 ovules per loculus

Trees or large shrubs; fruit not angular

Small shrubs; fruit prominently angular

(from 178)

Leaves gland-dotted

Leaves not gland-dotted

Flowers hypogynous

Flowers perigynous or epigynous

Leaves simple, reduced to phyllodes, or absent

Leaves compound

(1) Stamens free or only slightly united at base

(2) Stamens united into 5 or 10 groups

(3) Stamens united into a single group

Flowers small, in globular heads or obloid or
cylindrical spikes; stamens much exserted

Flowers not as above; stamens usually not exserted

Flowers hypogynous
Flowers perigynous
(1) Shrubs; leaves fleshy, entire

(2) Shrubs, trees or climbers; leaves not fleshy; leaf
margins entire, pinnately toothed or lobed

(3) Small trees; leaves palmately divided into 5 or 7
lobes

Calyx caducous

Calyx not caducous

Anthers dehiscing by terminal pores or slits

Anthers dehiscing longitudinally

Ovary 2— or more-locular

Ovary 1-locular

Petals yellow, large

Petals not yellow, small

Ovary adnate to one side of throat of calyx

Ovary free or completely adnate to calyx

Stamens inserted with petals at rim of hypanthium;
ovules 1 or 2 in the ovary

Stamens inserted on hypanthium below rim
(sometimes almost at base); ovules usually
numerous

Anthers 1—locular

Anthers 2-locular

Key to families

Sapindaceae
234

Burseraceae
Zygophyllaceae

236
237

Rutaceae
Myrtaceae

238
249

239
Tiliaceae
248

Mimosaceae
240

241
246

Zygophyllaceae
242

Bixaceae

Bixaceae
243

Elaeocarpaceae
244

Tiliaceae
245

Dilleniateae
Flacourtiaceae

Chrysobalanaceae
247

Rosaceae

Lythraceae

Malvaceae
Bombacaceae

127

Key to families

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

128

(from 237)

Leaves pinnate or bipinnate

Leaves palmate

Petals valvate

Petals imbricate

(from 157)

Leaves simple or absent

Leaves compound

Leaves opposite or verticillate
Leaves alternate, radical, or absent
Stamens 10 or fewer

Stamens indefinite

Styles or stigmas 5

Styles or stigmas less than 5

Leaves opposite

Leaves verticillate

Leaves gland-dotted

Leaves not gland-dotted

Floating aquatic plants without roots
Plants not aquatic

Styles 5, free

Style 1, with 5 stigmas

Ovary 1-locular

Ovary 2-5-locular

Ovary 1-locular

Ovary 3- or more-locular

Leaves palmately lobed

Leaves otherwise

Styles free

Styles united, stigmas 2 or more
Climbers or twiners

Non-climbers, non-twiners

Leaves gland-dotted

Leaves not gland-dotted

Mostly herbs; stems usually swollen at nodes
Shrubs or trees; nodes not swollen
Petals much more than 2 mm long, distinctly clawed
Petals scarcely 2 mm long, sessile or nearly so
Herbs, non-climbers, non-twiners
Shrubs, trees, climbers or twiners

250

Bixaceae
Mimosaceae
Caesalpiniaceae

252

307

253

274

254

272

255

261

256

257

Rutaceae

258

Droseraceae
Caryophyllaceae
259

260
Caryophyllaceae
Elatinaceae
Caryophyllaceae
Geraniaceae
Aceraceae

262

263

267
Malpighiaceae
264

Clusiaceae

265
Caryophyllaceae
266
Malpighiaceae
Cunoniaceae
Caryophyllaceae
268

268

269

270

271

272

273

274

275

276

277

278

279

280

281

(1) Stamens 3

(2) Stamens 5 or 6

(3) Stamens 10

Stamens opposite to and enclosed in petals

Stamens opposite sepals

Petals clawed, the claws cohering in an angular tube
Petals sessile or if clawed, the claws free

Petals sessile; stamens 5

Petals clawed; stamens usually more than 5

(from 253)

Leaves in whorls of six

Leaves opposite

Juice resinous; stipules absent

Juice not resinous; stipules present

(from 252)

Stamens united, often forming a conspicuous staminal
tube

Stamens free or arising from margin of a small disc

Styles 2 or more, free

Style 1, with 2 or more stigmas

Stamens 5, 10, or indefinite

Stamens 8

Climbers

Non-climbers

Leaves usually dentate or lobed, with stellate hairs
Leaves entire, glabrous

Stamens 10

Stamens 4-5

Petals attached to base of staminal tube; staminal
tube usually long; stamens usually indefinite
(rarely 10 or fewer); stigmas usually 5
(occasionally fewer or up to 10); herbs, shrubs, or
trees

Not as above
(1) Style branches (or stigmas) 2 or 3; stamens
indefinite

(2) Style branches (or stigmas) 2 or 3; stamens 10 or
fewer

(3) Style branches (or stigmas) 5

Key to families

Hippocrateaceae
269
Malpighiaceae
Rhamnaceae

270
Frankeniaceae
271

Celastraceae
Malpighiaceae

Cunoniaceae
273

Clusiaceae
Cistaceae

275
283

276
280

277
Aizoaceae

Linaceae

278
Sterculiaceae
279

Erythroxylaceae
Linaceae

a
Malvaceae
281

Theaceae

Linaceae
282

129

Key to families

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

130

(1) Stamens 5 usually with alternating staminodes;
herbs or shrubs; leaves often with stellate hairs

(2) Stamens 5; staminodes 5; glabrous herbs; leaves
entire

(3) Stamens 10, usually 3 or 4 without anthers

(4) Stamens 10 or indefinite; staminodes sometimes
present; leaves often with stellate hairs

(trom 274)

(1) Stamens 1-3

(2) Stamens 5

(3) Stamens 6-10

(4) Stamens indefinite; flowers hypogynous

(5) Stamens indefinite; flowers perigynous

Flowers hypogynous

Flowers epigynous

Climbers with axillary tendrils

Non-climbers, or climbers without axillary tendrils

Corona present within corolla

No corona present

Styles 2 or more, free

Style 1, with 2 or more stigmas

Stamens opposite petals

Stamens alternating with petals

Styles 5

Styles less than 5

(1) Leaves with conspicuous glandular hairs

(2) Leaves small, appressed to stem

(3) Not as in (1) or (2) above

Staminodes present; fruit a capsule

Staminodes absent; fruit a drupe

Leaves small, appressed to stem

Leaves not appressed to stem

Stamens opposite petals

Stamens alternating with petals

(1) Herbs; stamens 5; staminodes absent

(2) Herbs; stamens 5; staminodes 5

(3) Shrubs or trees

Fruit a schizocarp

Fruit a capsule

Flowers hypogynous

Flowers perigynous or epigynous

Sterculiaceae

Linaceae
Geraniaceae

Sterculiaceae

284

285

299

305

Rosaceae
Tiliaceae
Donatiaceae
286

287
Passifloraceae
Plumbaginaceae
288

292

289

290
Plumbaginaceae
Rhamnaceae
Droseraceae
Tamaricaceae
291

Linaceae
Dichapetalaceae
Tamaricaceae
293
Rhamnaceae
294

295
Geraniaceae
296
Stackhousiaceae
Saxifragaceae
297
Saxifragaceae

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

Ovary 1-locular

Ovary 2- or more-locular
Hypogynous disc present

Hypogynous disc absent

(from 283)

Leaves peltate

Leaves not peltate

Stamens 8, 6 of them attached to base of corolla
Stamens all hypogynous or perigynous
Stamens 10, all with anthers

Stamens 7-10; if 10, some without anthers
Style 1, with 2 or more stigmas

Styles several, free

Flowers hypogynous; sepals free
Flowers perigynous or epigynous; sepals united
Herbs

Shrubs or trees

(from 283)

Sepals valvate or united

Sepals imbricate

Petals deeply incised

Petals entire

(from 251)

Leaves alternate or radical

Leaves opposite

Styles or sessile stigmas, free

Style 1, with 2 or more stigmas

Herbs

Shrubs or trees

Stamens 5

Stamens 10

Styles 2; leaflets 2, occasionally one

Styles more than 2, or if 2 the leaflets more than 2

(1) Stamens 3; staminodes 2-5; style petaloid
(2) Stamens 5; staminodes absent

(3) Stamens 5, alternating with 5 usually scale-like

staminodes
(4) Stamens more than 5
(1) Stamens 6-9; stigmas not plumose
(2) Stamens 10; stigmas plumose
(3) Stamens indefinite

Key to families

Icacinaceae
298

Dichapetalaceae
Grossulariaceae

Tropaeolaceae
300

Polygalaceae
301

302
Geraniaceae

303
304

Geraniaceae
Saxifragaceae

Saxifragaceae
Anacardiaceae

306
Actinidiaceae

Elaeocarpaceae
Tiliaceae

308

314

309

312

310

311
Droseraceae
Oxalidaceae
Sapindaceae
Anacardiaceae
Caesalpiniaceae
Anacardiaceae

Geraniaceae
313
Sapindaceae
Simaroubaceae
Bombacaceae

131

Key to families

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

132

Leaves with 3 leaflets
Leaves with more than 3 leaflets
(1) Herbs; style simple with 1-5 sessile stigmas

(2) Herbs or small shrubs; style with 5 short stigmatic
branches

(3) Trees

(from 156)

Stamens 5

Stamens more than 5

Stamens opposite petals
Stamens alternating with petals
Parasitic shrubs (mistletoes)
Plants not parasitic

(1) Leaves gland-dotted

(2) Leaves not gland-dotted; stamens attached to
petals at their bases

(3) Leaves not gland-dotted; stamens free from petals

Leaves gland-dotted

Leaves not gland-dotted

Herbs, non-climbing, non-twining

Shrubs or trees, sometimes climbing or twining

Flowers in umbels or heads; styles or stigmas 2

Flowers not in umbels or heads; style and stigma 1

Flowers in umbels

Flowers not in umbels

Leaves compound

Leaves simple

Flowers in elongated spikes; indumentum stellate

Flowers racemose or subsolitary; hairs simple or
glandular

Fruit a schizocarp, separating into two flattened
mericarps when mature

Fruit a berry or drupe

(from 316)

Leaves gland-dotted

Leaves not gland-dotted

(1) Stamens indefinite

(2) Stamens 10, alternating with staminodes

(3) Stamens 10 or fewer; staminodes absent

Ovary 1-locular

Ovary 2- or more-locular

Cunoniaceae
315

Zygophyllaceae

Geraniaceae
Cunoniaceae

317
327

318
320

Loranthaceae
319

Myrtaceae

Alangiaceae
Rhamnaceae
Myrtaceae
321

322

323
Apiaceae
Onagraceae
326

324
Araliaceae
325

Hamamelidaceae

Grossulariaceae

Apiaceae
Araliaceae

328

330
Myrtaceae
Myrtaceae
329
Combretaceae
Myrtaceae

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

Leaves alternate, radical, or absent

Leaves opposite

Leaves simple

Leaves compound

Stamens 2 or 3 opposite each petal

Stamens indefinite, not regularly opposite petals

Style and stigma 1

Styles or stigmas more than 1

(1) Stamens 6, attached to petals

(2) Stamens 10

(3) Stamens indefinite

Stamens 10 or fewer

Stamens indefinite

Herbs

Shrubs (sometimes climbing) or trees

Ovary 1-locular

Ovary 2- or more-locular

Leaves simple or absent

Leaves compound

Leaves with several conspicuous longitudinal veins

Midrib the only conspicuous longitudinal vein

Stamens usually 10, rarely up to 13

Stamens indefinite

Style 1, stigmas 1 or 2

Styles 3

Leaves unequal, one of each pair much larger than
other; anthers with conspicuous appendages

Leaves of each pair equal; anthers without
appendages

Ovary 1-locular

Ovary 2- or more-locular

Trees of sea-shores or salt creeks

Plants not growing in salt water

Petals sessile or with very short claws

Petals with slender claws

Leaves petiolate

Leaves sessile

(from 79)

Flowers with one or more long spurs

Flowers without a spur

Key to families

331

338

333

332
Flacourtiaceae
Rosaceae

335

334
Alangiaceae
Anacardiaceae
Rosaceae

336

Rosaceae
Onagraceae
337
Combretaceae
Grossulariaceae
339

346
Melastomataceae
340

341
Punicaceae
342

345

Melastomataceae

343

Combretaceae
344

wa
Rhizophoraceae
Saxifragaceae
Saxifragaceae
Malpighiaceae
Cunoniaceae
Saxifragaceae

Ranunculaceae
348

133

Key to families

348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

363

364

365

134

(1) Sepals 2; style short or absent; stigmas usually
confluent

(2) Sepals 2; styles several, free, or style 1 with
several free stigmas; plants more or less fleshy

(3) Sepals more than 2, or whole perianth petaloid or
sepaloid

Ovary superior

Ovary inferior

Aquatic herbs with floating or submerged leaves

Herbs (not aquatic), shrubs, or trees

Leaves alternate

Leaves opposite or verticillate

Climbers

Non-climbers

Tendril climbers

Not tendril climbers

Branches spiny

Branches not spiny

One perfect stamen (much longer than the others)
and usually 4 or more imperfect stamens

Perfect stamens 5 or more

Leaves simple or absent

Leaves compound

Flowers hypogynous

Flowers perigynous

Stamens hypogynous or inserted low in hypanthium

Stamens inserted on rim of hypanthium

Herbs

Shrubs or trees

Ovary open at top, with sessile stigmas

Ovary closed; style present

Stamens 6-9

Stamens 10 or indefinite

Plants spiny

Plants without spines

Perianth segments 3 + 3 + 3; styles indefinite

Sepals 5 or more; styles or stigmas 5 or fewer

Bracteoles present, merging into sepals

Bracteoles absent or small

Stamens 6

Stamens 10

Papaveraceae
Portulacaceae

349

350

370
Nymphaeaceae
351

352

366

353

355
Passifloraceae
354

Cactaceae
Menispermaceae

Anacardiaceae
356

357

365

359

358
Lythraceae
Rosaceae

360

361
Resedaceae
Amaranthaceae
362

363
Berberidaceae
Flacourtiaceae
Magnoliaceae
364

Theaceae
Flacourtiaceae
Berberidaceae
Mimosaceae

366

367

368

369

370

371

372

373

374

375

376

377

378

379

380

381

(from 351)
Leaves simple

Leaves compound, with 3 leaflets (each pair looking

like a whorl of 6 leaves)
Ovary 3-6-locular
Ovary 10—-15-locular
Leaves with 5-7 conspicuous longitudinal veins
Midrib the only conspicuous longitudinal vein

Stamens inserted on the hypanthium; anthers opening

longitudinally

Stamens at base of hypanthium; anthers opening by

terminal pores
(from 349)
Aquatic herbs
Herbs (not aquatic), shrubs, or trees
(1) Leaves alternate or clustered
(2) Leaves opposite
(3) Leaves absent
Branches spiny
Branches without spines
Plants fleshy, leafless
Plants woody, with leaves
Plants parasitic (mistletoes)
Plants not parasitic
Leaves fleshy
Leaves not fleshy
Leaves simple
Leaves palmate
Stamens (+ staminodes if present) indefinite
Stamens less than 10
Style 1, stigma 1
Stigmas indefinite, sessile on flat surface of ovary
(1) Style 1, stigmas 2
(2) Styles or stigmas 3-5
(3) Stigma 1, sessile
(from 371)
Leaves fleshy; stigmas 5
Leaves not fleshy; stigmas 1 or 2
(1) Petals absent; leaves gland-dotted
(2) Petals absent; leaves not gland-dotted
(3) Petals present

Key to families

367

Cunoniaceae

368
Sonneratiaceae

Melastomataceae
369

Lythraceae

Melastomataceae

Nymphaeaceae
371

372

380

Cactaceae

373

374

Cactaceae
Punicaceae
Loranthaceae
375

Aizoaceae

376

377
Araliaceae
378

379
Punicaceae

; Eupomatiaceae
Alangiaceae
Flacourtiaceae
Combretaceae

Aizoaceae

381

Myrtaceae
Sonneratiaceae
382

135

Key to families

382

383

384

385

386

387

388

389

390

391

392

393

394

395

396

397

398

399

136

Leaves with 5-7 conspicuous longitudinal veins
Midrib the only conspicuous longitudinal vein
Sepals and petals each indefinite

Sepals and petals each less than 10

Stamens less than 20

Stamens 20 or more

Ovary 1-locular, with about 10 ovules

Ovary 2-5-locular, with 1-2 ovules per loculus
(from 11)

Flowers unisexual

Flowers mostly bisexual

Leaves opposite

Leaves alternate

Ovary superior

Ovary inferior

Gynoecium apocarpous

Gynoecium syncarpous or carpel 1

Fruit a berry

Fruit 1-4 nutlets

Perianth segments in 2 whorls

Perianth segments in 1 whorl

Ovary inferior

Ovary superior

Stamens 6 or more in regular series around a

disc-like axis; perianth shallow, cup-shaped, entire

to slightly lobed
Stamens l1—many, not arranged as above; sepals
evidently lobed
Sepals 4; petals 4
Sepals and petals each 5 or more
Climbers
Non-climbers
Ovary superior
Ovary inferior
Stamens 5 in male flowers
Stamens usually 10 in male flowers
Fruit a capsule
Fruit a nut or drupe
Placentation parietal
Placentation axile

Melastomataceae
383

Rhizophoraceae
384

385

Punicaceae

Combretaceae
Rhizophoraceae

387

400

388

391

389
Rubiaceae
Monimiaceae
390
Theaceae
Lamiaceae
394

392
Araliaceae
393

Gyrostemonaceae

Euphorbiaceae
395

396
Menispermaceae
Ebenaceae

397

399

398

Ebenaceae
Solanaceae
Olacaceae
Cucurbitaceae
Campanulaceae

400

401

402

403

404

405

406

407

408

409

410

411

412

413

414

415

416

(from 386)

Ovary superior

Ovary inferior or half-inferior

(1) Stamens 2

(2) Stamens 3

(3) Stamens 4

(4) Stamens 5

(5) Stamens more than 5

Ovary entire or slightly lobed

Ovary divided into (usually 4) free or nearly free
segments

Flowers actinomorphic

Flowers zygomorphic

Leaves simple or absent

Leaves compound

(1) Corolla-lobes 4

(2) Corolla-lobes 5

(3) Corolla-lobes more than 5

(1) Herbs

(2) Shrubs or undershrubs

(3) Climbers

Flowers in long terminal spikes

Flowers not in spikes

Style minutely notched at top

Style deeply divided into 2 branches

Bracteoles large, more or less covering calyx

Bracteoles absent or small

Calyx divided into 2 lobes or segments

Calyx divided into more than 2 lobes or segments

Leaves opposite

Leaves, if present, alternate or radical

Leaves radical or alternate

Leaves opposite

Ovary 1-locular; placentation parietal

Ovary 2-locular; placentation axile

Leaves with viscid hairs

Leaves glabrous or hairs, if present, not viscid

Ovary 1-locular

Ovary 2- or more-locular

Seeds endospermic

Seeds not endospermic

Key to families

401
544

402
Olacaceae
418
463
529

403

Lamiaceae

404
409

405
Oleaceae

Oleaceae
406
Oleaceae

Scrophulariaceae
407
Oleaceae

Verbenaceae
408

Oleaceae
Verbenaceae

Acanthaceae
410

411
412

Verbenaceae

_ Lentibulariaceae

413
414

Gesneriaceae
Solanaceae

Pedaliaceae
415

Gesneriaceae
416

Scrophulariaceae
417

137

Key to families

417

418

419

420

421

422

423

424

425

426

427

428

429

430

431

432

433

434

138

Fruit a capsule

Fruit a drupe or divided into nutlets

(from 401)
Ovary apocarpous

Ovary syncarpous or carpel 1
Flowers actinomorphic or nearly so
Flowers zygomorphic

(1) Leaves alternate, bipinnate
(2) Leaves alternate or absent in mature plant, not

bipinnate

(3) Leaves opposite or verticillate

(4) Leaves radical

Sepals 4, free; petals 4, united
Sepals 5, free; petals 5, united

(1) Corolla-lobes 3
(2) Corolla-lobes 4
(3) Corolla-lobes 5

Stamens alternating with corolla-lobes
Stamens opposite corolla-lobes

Twining plants
Prostrate annuals
Leaves absent
Leaves present

Ovary 1-locular with several ovules
Ovary 2-locular with 1 ovule per loculus

Leaves absent
Leaves present

Leaves with viscid hairs
Leaves glabrous or hairs, if present, not viscid

Seeds endospermic

Seeds non-endospermic

Anthers connivent around the style
Anthers not connivent

Fruit a drupe

Fruit a capsule or berry

(from 420)

Ovary divided into (usually 4) separate segments
Ovary entire or lobed

Style terminal

Style gynobasic, rarely terminal

Sepals 4

Sepals 5 or more, or calyx 2-lipped or truncate

Acanthaceae
Verbenaceae

Monimiaceae
419
420
445

Mimosaceae

422

432

421
Plantaginaceae
Acanthaceae
Polygalaceae
423

427

424

426

425
Boraginaceae
Cuscutaceae
Cardiopteridaceae
Myrsinaceae
Sapotaceae
Cuscutaceae
428

429

430
Solanaceae
Pedaliaceae
Solanaceae
431
Myoporaceae
Solanaceae

433

434
Verbenaceae
Lamiaceae
435

440

435

436

437

438

439

440

441

442

443

444

445

446

447

448

449

450

(1) Ovary 1-locular, with 2 parietal placentas

(2) Ovary 2-locular

(3) Ovary 4-locular

Herbs

Shrubs or trees

Leaves in whorls, usually of 3

Leaves opposite

Ovary quite superior

Ovary half-inferior

Capsule circumscissile

Capsule septicidal

Corolla 4—lobed

Corolla 5—lobed

Leaves simple or absent

Leaves compound

Bracteoles large, more or less enclosing calyx

Bracteoles absent or not enclosing calyx

Placentas axile

Placentas parietal

(1) Ovary 2-locular, with several ovules; herbs or
small shrubs

(2) Ovary 2-locular, with numerous ovules; trees

(3) Ovary 4-locular, with 1 ovule per loculus

(from 419)

(1) Leaves all simple or reduced to scales

(2) Leaves all compound

(3) Leaves variable

Leaves opposite, the upper ones sometimes becoming
alternate

Leaves mostly in whorls of 3

Upper leaves simple, lower leaves compound; ovary
2- or 4locular with 1-many ovules per loculus

Leaves very variable, simple or with 3-5 leaflets;
ovary 2-locular with 2 ovules per loculus

Leaves reduced to scales; plants without chlorophyll

Leaves not reduced to scales; plants green

(1) Leaves radical

(2) Upper leaves alternate, lower leaves opposite

(3) Leaves all alternate

(4) Leaves all opposite or verticillate

Ovary 2-locular

Ovary 4-locular

Key to families

Gentianaceae
436
Verbenaceae

437
Loganiaceae

Scrophulariaceae
438

439

Rubiaceae
Plantaginaceae
Loganiaceae

Verbenaceae
441

442
Bignoniaceae

Acanthaceae
443

444
Gesneriaceae

Scrophulariaceae
Bignoniaceae
Verbenaceae

448
460
446

447
Bignoniaceae

Pedaliaceae

Verbenaceae
Orobanchaceae
449
Scrophulariaceae
450

451

456
Scrophulariaceae
Pedaliaceae

139

Key to families

451

452

453

454

455

456

457

458

459

460

461

462

463

464

140

Calyx of 3 outer and 2 inner sepals, all free; petals 3,
united

Calyx of 5 free or united sepals in 1 whorl; petals 5,
united

Ovary 2-locular

Ovary 4-locular

Herbs (sometimes climbing)

Shrubs or small trees

Corolla actinomorphic or nearly so, usually spreading

Corolla 2-lipped

Stigmas 2; fruit a capsule or berry

Stigma 1; fruit a drupe

Ovary divided into 4 nearly separate segments at
maturity

Ovary simple or lobed

(1) Ovary 1-locular; ovules numerous

(2) Ovary 2-locular

(3) Ovary 4-locular with 1 ovule per loculus

(4) Ovary 8-locular with 1 ovule per loculus

Bracteoles conspicuous, often more or less covering
calyx

Bracteoles small or absent

(1) Undershrubs, shrubs or woody vines, rarely trees;
ovules 1 or 2 per loculus

(2) Herbs or small shrubs; ovules 2 or more per
loculus

(3) Small or large trees; ovules numerous

(from 445)

Climbers, usually woody

Shrubs or trees

(1) Leaves with 3 leaflets; fifth stamen represented by
a staminode

(2) Leaves with 3 leaflets; fifth stamen absent

(3) Leaves with more than 3 leaflets

Ovules 2 per loculus; fifth stamen absent

Ovules more than 2 per loculus; fifth stamen usually
represented by a staminode

(from 401)

Latex present

Latex absent

(1) Leaves alternate

(2) Leaves opposite or verticillate

(3) Leaves absent

Polygalaceae

452

453
Myoporaceae
454

455

Solanaceae
Scrophulariaceae
Solanaceae
Myoporaceae

Lamiaceae
457

Gesneriaceae
458
Verbenaceae
Pedaliaceae

Acanthaceae
459

Verbenaceae

Scrophulariaceae
Bignoniaceae

Bignoniaceae
461

Bignoniaceae
Verbenaceae
462

Verbenaceae

Bignoniaceae

464
471
465
470
Asclepiadaceae

465

466

467

468

469

470

471

472

473

474

475

476

477

478

479

480

481

Twiners

Non-twiners

Fruits winged

Fruits not winged

Flowers actinomorphic

Flowers zygomorphic

Anthers connivent around or above stigma

Anthers free

Stamens alternating with lobes or angles of corolla

Stamens opposite corolla-lobes

Stamens lacking a coronal appendage; pollen grains
single

Stamens mostly with a coronal appendage; pollen
grains cohering in tetrads or pollinia

Leafless parasites

Leafy plants

Gynoecium apocarpous or divided into 2 or more
free segments

Gynoecium syncarpous, the ovary entire or lobed, or

carpel 1
(1) Leaves alternate or radical
(2) Leaves opposite or verticillate
(3) Leaves absent
Inflorescence a monochasial cyme, uncoiling as the
flowers open
Inflorescence not as above
Plants slender, creeping perennials, rooting at nodes
Plants more or less erect
Perianth segments (calyx plus corolla) 10 or fewer
Perianth segments about 15
(1) Leaves verticillate
(2) Leaves opposite
(3) Leaves alternate, in alternate pairs, or clustered
Leaves compound
Leaves simple
Leaves stipulate
Leaves exstipulate
Shrubs or trees
Floating herbs
Flowers actinomorphic
Flowers zygomorphic

Key to families

466
467

Cardiopteridaceae
Convolvulaceae

468
Campanulaceae

Apocynaceae
469

Convolvulaceae
Sapotaceae

Apocynaceae

Asclepiadaceae

Cuscutaceae
472

473

477
474
476
Asclepiadaceae

Boraginaceae
475
Convolyulaceae
Boraginaceae
Apocynaceae
Monimiaceae
480

w 481

478

479

496
Mimosaceae
Leeaceae
Apocynaceae
Droseraceae
482

494

141

Key to families

482

483

484

485

486

487

488

489

490

491

492

493

494

495

496

497

498

142

Leaves simple

Leaves compound

(1) Style 1, with 1 or 2 stigmas

(2) Style 1, with 3 branches

(3) Style 1, with 4 branches

(4) Styles or style branches 5

(5) Style 1, apex divided into many minute stigmatic
branches

Inflorescence a monochasial cyme

Inflorescence not a monochasial cyme

Anthers cohering about style

Anthers quite free

Herbs

Shrubs

Leaves opposite

Leaves alternate

Stamens alternating with corolla-lobes

Stamens opposite corolla-lobes

Ovary 1-locular

Ovary 2- or 4-locular

Stipules small, scarious

Stipules absent

Plants (including the inflorescence) densely covered
with cottony or woolly hairs

Not as above

Leaves all opposite, usually stipulate

Leaves on non-flowering parts alternate, exstipulate

Stamens free from corolla

Stamens epipetalous

(from 481)

Leaves simple

Leaves compound

Ovary 4— or occasionally 2-locular

Ovary 1-locular; leaves with viscid hairs

(from 478)

Petals 3

Petals 4 or 5

Style with indusium

No indusium present

Corolla actinomorphic or nearly so

Corolla zygomorphic, usually split down one side

483
Bignoniaceae
484

493
Polemoniaceae
Plumbaginaceae

Nyctaginaceae
Boraginaceae
485

486

488
Caryophyllaceae
487
Apocynaceae
Solanaceae

489

Primulaceae

490

491
Caryophyllaceae
Gentianaceae

Verbenaceae
492
Loganiaceae
Solanaceae
Frankeniaceae
Polemoniaceae

495
Bignoniaceae

Verbenaceae
Pedaliaceae

Polygalaceae
497
498
499
Brunoniaceae
Goodeniaceae

499

500

501

502

503

504

505

506

507

508

509

510

511

512

513

Flowers zygomorphic
Flowers actinomorphic
(1) Stamens free from petals

(2) Stamens free from but usually detached with
petals

(3) Stamens distinctly epipetalous, though sometimes
attached near the base of corolla-tube

Stigmas 1 or 2

Stigmas 4 or 5

Stamens opposite corolla-lobes

Stamens alternating with corolla-lobes |

Nectar-secreting disc conspicuous, embedding base of
ovary

Nectar-secreting disc absent

Ovary 1-locular with several ovules

Ovary 2- or more-locular with 1 ovule per loculus

Herbs

Trees, shrubs, climbers, or twiners

Leaves with glandular hairs; corolla segments only
united in short ring at base

Leaves not as above; corolla segments cohering to
form a tube, but free right at the base

Calyx covered at base with usually numerous
imbricate sepaloid bracteoles

Bracteoles absent, or not covering base of calyx

Anthers versatile; ovules 1 or 2 in ovary

Anthers not versatile; ovules more than two in ovary

(from 500)

Inflorescence a monochasial cyme

Inflorescence not a monochasial cyme

Style 1, with 1 or more stigmas

Styles 2, free

Fruit a capsule or berry

Fruit a drupe or divided into nutlets

(1) Style 1, with 1 or 2 stigmas, or stigma sessile

(2) Style 1, with 3 stigmas

(3) Style 1, with 4 stigmas

(4) Style 1, with 5 stigmas

(5) Style 1, with 6-8 stigmas

(6) Styles 2, free

(7) Styles 5, free

Stamens opposite corolla-lobes

Stamens alternating with corolla-lobes

Key to families

Solanaceae
500

501
Pittosporaceae

509
502
Plumbaginaceae
503
505

Olacaceae
504
Myrsinaceae
Sapotaceae
506

507

Byblidaceae

Stackhousiaceae

Epacridaceae
508

Olacaceae
Pittosporaceae

510

512

511
Hydrophyllaceae
Solanaceae
Boraginaceae
513
Polemoniaceae
527
Plumbaginaceae
Convolyulaceae
528
Plumbaginaceae
514

516

143

Key to families

514

515

516

517

518

519

520

521

522

523

524

525

526

527

144

Herbs

Shrubs or trees

Ovary 1-locular, with central placenta

Ovary 2- or more-locular

Leaves simple or absent from mature plant

Leaves compound

Herbs, growing in marshes or in water

Herbs (not aquatic), shrubs or trees, sometimes
climbers

Base of calyx more or less covered by imbricate
bracts and bracteoles; bracteoles sometimes only 2

Bracteoles absent, or not covering base of calyx

Climbers, twiners, or prostrate plants

Plants more or less erect

Anthers connivent in cone around style, dehiscing by

pores or slits; ovary 2—locular, usually with many
ovules

Anthers not connivent; ovary 1—2-locular; ovules 2
or 4 per loculus

(1) Herbs (sometimes coarse), usually annual; ovules
2 or more per loculus

(2) Coarse annuals; ovules | per loculus

(3)Shrubs or small trees

(1) Ovary 1-locular

(2) Ovary 2-locular

(3) Ovary 3-locular

(4) Ovary 4-locular

(5) Ovary usually 5-locular

(1) Ovules 1 per loculus

(2) Ovules 2 per loculus

(3) Ovules more than 2 per loculus

Fruit a drupe or nut; ovules 1 per loculus

Fruit a berry or capsule; ovules usually more than 1
per loculus

Tendril climbers

Not tendril climbers but sometimes twiners

Leaves palmate

Leaves pinnate

(from 512)

Usually annuals, with slender creeping or trailing
stems; ovary 2-locular

Tall shrubs or trees; ovary 4-locular

Primulaceae
515

Myrsinaceae
Sapotaceae
517

525

Menyanthaceae

518

Epacridaceae
519

520
521

Solanaceae

Convolvulaceae

Solanaceae
Boraginaceae
522
Monimiaceae
523
Solanaceae
524
Epacridaceae
Myoporaceae
Boraginaceae
Solanaceae

Boraginaceae

Solanaceae
Polemoniaceae
526
Convolvulaceae
Solanaceae

Convolvulaceae
Boraginaceae

528

529

530

531

532

533

534

535

536

537

538

539

540

541

542

543

(from 512)

(1) Each of the 2 styles divided into 2 branches

(2) Each style simple; ovary 2-locular, with
numerous ovules

(3) Each style simple; ovary 2-locular, with 2 ovules
per loculus

(from 401)

Latex present

Latex absent

(1) Leaves simple or reduced to phyllodes

(2) Leaves pinnatisect

(3) Leaves compound

Gynoecium apocarpous

Gynoecium syncarpous or carpel 1

Style 1

Styles as many as carpels

Perfect stamens alternating with staminodes
(sometimes scale-like)

Stamens all perfect

Stamens 10 or fewer

Stamens indefinite

Style 1, the apex divided into many minute stigmatic
branches

Styles or stigmas 5 or fewer, apex not as above

Stamens free

Stamens united

Stamens free from corolla, hypogynous

Stamens epipetalous

Style and stigma 1

Styles or stigmas 2 or more

Ovary of 1 carpel, 1-locular; style and stigma 1

Ovary syncarpous, mostly 3—5-locular; styles or
stigmas 2 or more

Pedicel with a pair of bracts

Pedicel lacking bracts

(from 530)

Leaves bipinnate

Leaves pinnate or 3-foliolate

Gynoecium apocarpous

Gynoecium syncarpous or carpel 1

Style 1; ovary 1-locular

Styles 3-5; ovary 3—5-locular

Key to families

Convolyulaceae

Hydrophyllaceae

Convolyulaceae

Sapotaceae
530

531
Ranunculaceae
541

532
533

Rutaceae
Crassulaceae

Sapotaceae
534

535
539

Nyctaginaceae
536

537
Polygalaceae
Ericaceae
538
Solanaceae
Ebenaceae

Mimosaceae

“a

540

Theaceae
Actinidiaceae

Mimosaceae
542

Crassulaceae
543

Mimosaceae
Oxalidaceae

145

Key to families

544

545

546

547

548

549

550

551

552

553

554

555

556

557

558

559

560

146

(from 400)

Leaves opposite or verticillate
Leaves alternate, radical, or absent
(1) Petals 4

(2) Petals 5

(3) Petals more than 5
Leaves simple

Leaves compound

Stamens free from petals
Stamens epipetalous

Ovary 1-locular

Ovary 2-5-locular

(1) Stamen 1

(2) Stamens 4

(3) Stamens 5

Flowers in heads surrounded by involucre of bracts
Flowers not in heads
Herbs

Shrubs

Plants parasitic (mistletoes)
Plants not parasitic
Stamens epipetalous
Stamens free from petals
Style expanded into an indusium
Style without indusium
Flowers actinomorphic
Flowers zygomorphic
Leaves stipulate

Leaves exstipulate

(from 545)

Style 1, stigmas 1 or 2
Styles or stigmas 3 or 5
Plants parasitic (mistletoes)
Plants not parasitic

(from 544)

Plants parasitic (mistletoes)
Plants not parasitic

(1) Stamens 2; gynandrous
(2) Stamens 3

(3) Stamens 4

(4) Stamens 5

(5) Stamens more than 5

545

559

546

549

557

547
Caprifoliaceae
548

Rubiaceae
Grossulariaceae
Campanulaceae
Valerianaceae
550

552
Dipsacaceae
551
Gesneriaceae
Caprifoliaceae
Loranthaceae
553

555

554
Goodeniaceae
Campanulaceae
556
Caprifoliaceae
Rubiaceae
Caprifoliaceae

558
Rubiaceae
Loranthaceae
Rubiaceae

Loranthaceae
560
Stylidiaceae
Cucurbitaceae
Campanulaceae
561

569

561

562

563

564

565

566

567

568

569

570

571

572

573

574

575

576

577

Style expanded into an indusium
Style without indusium

Flowers actinomorphic

Flowers zygomorphic, corolla-tube usually split down

one side

Prostrate plants or climbers; tendrils large

Non-climbers; tendrils absent

Stamens alternating with corolla-lobes

Stamens opposite corolla-lobes

Ovary 1-locular

Ovary 2-— or more-locular

Stems more or less succulent, hollow; flowers in
dense spikes

Stems not succulent, solid; flowers racemose or
axillary

Fruit a capsule

Fruit a berry

(1) Herbs

(2) Trees or climbers; stigma 1

(3) Trees; stigmas 3

(1) Stamens 6

(2) Stamens 10

(3) Stamens indefinite

Leaves persistent

Leaves, if present, caducous

Leaves gland-dotted

Leaves not gland-dotted

(from 10)

Flowers unisexual

Flowers mostly bisexual

Leafless stem parasite embedded in host; only the

flowers emergent
Not an embedded parasite (though sometimes
leafless)
Leaves or scales in whorls of 3 or more
Leaves or scales alternate, opposite, or absent
Aquatic herbs
Shrubs or trees
Ovary inferior
Ovary superior
Latex present
Latex absent

Key to families

Goodeniaceae
562

563

Campanulaceae

Cucurbitaceae
564

565
568

Menyanthaceae
566

Sphenocleaceae

567
Campanulaceae
Epacridaceae

Primulaceae
Myrsinaceae
Alangiaceae

Alangiaceae
Ericaceae
570

571
Cactaceae

Myrtaceae
Symplocaceae

573
647

Rafflesiaceae

574

575
577

576
Casuarinaceae

Haloragaceae
Ceratophyllaceae
578

580

147

Key to families

578

579

580

581

582

583

584

585

586

587

588

589

590

591

592

593

594

148

Separate male and female flowers inside pear-shaped
receptacle which opens by narrow aperture at top

Not as above

Leaves stipulate; ovary 1-locular with 1 ovule

Leaves exstipulate; ovary 2— or more-locular

(1) Perianth segments 2

(2) Perianth segments 3

(3) Perianth segments 4

(4) Perianth segments 5 or more, or perianth
obscurely lobed or truncate

Ovary superior

Ovary inferior

Climbers

Non-climbers

Ovary 1-locular; styles 2

Ovary 2-3-locular; styles 2 or 3

Leaves stipulate

Leaves exstipulate

Flowers minute, in heads, surrounded by involucre of
bracts

Flowers not in heads

Ovary inferior

Ovary superior

Herbs

Parasitic shrubs (mistletoes)

Succulent root parasites without chlorophyll, 5-10
cm high with scale-like leaves

Herbs, shrubs, or trees, not parasitic

Style or stigma 1

Styles or style branches 2 or more

Stigma penicillate

Stigma not penicillate

Leaves simple

Leaves compound

Leaves with 7-20 primary veins on each side of
midrib

Midrib the only prominent vein, if any

Ovary 1-locular, with 1 ovule

Ovary 2-3-locular

Leaves stipulate

Leaves exstipulate

Moraceae

579

Moraceae
Euphorbiaceae
581

586

595

614

582

585
Menispermaceae
583

584
Euphorbiaceae

Urticaceae
Chenopodiaceae

Asteraceae
Gunneraceae
587

588
Gunneraceae
Viscaceae

Balanophoraceae
589

590
593
Urticaceae
591

592
Sapindaceae

Myristicaceae
Santalaceae
594
Euphorbiaceae
Polygonaceae
Amaranthaceae

595

596

597

598

599

600

601

602

603

604

605

606

607

608

609

610

(from 580)

(1) Leafless succulents, parasitic on roots

(2) Shrubs parasitic on stems (mistletoes)

(3) Plants not parasitic

Ovary or gynoecium superior

Ovary inferior

Gynoecium apocarpous

Gynoecium syncarpous or carpel 1

Styles free

Styles 4, connate

Leaves opposite

Leaves alternate

Leaves simple

Leaves compound

Leaf terminating in a tendril or pitcher provided with
a lid

Leaf not terminating in a tendril or pitcher, or leaves
absent

Styles or stigmas penicillate

Neither styles nor stigmas penicillate

(1) Style 1

(2) Styles 2

(3) Styles 3-6

Placentation axile

Placentation parietal

Leaves simple or absent

Leaves compound

(1) Leaves alternate, without stinging hairs, or leaves
absent

(2) Leaves alternate, with stinging hairs

(3) Leaves opposite

(1) Stamens 2 in male flowers

(2) Stamens usually 4 in male flowers

(3) Stamens 6 in male flowers

(4) Stamens 10 or indefinite in male flowers

Leaves not expanded at time of flowering; stigma
sessile

Leaves present at time of flowering

Leaves stipulate

Leaves exstipulate

Ovary glabrous

Ovary with hooked bristles

Key to families

Balanophoraceae
Viscaceae
596

597
612
598
601

599
Sterculiaceae

600
Phytolaccaceae

Monimiaceae
Ranunculaceae

Nepenthaceae

602
Urticaceae
603

605

Ulmaceae

604
Euphorbiaceae
Flacourtiaceae
606

611

607

Urticaceae
Urticaceae
Thymelaeaceae
608

Lauraceae

610

Santalaceae
609

Urticaceae
Phytolaccaceae

Flacourtiaceae
Phytolaccaceae

149

Key to families

611

612

613

614

615

616

617

618

619

620

621

622

623

624

625

626

627

150

Leaves stipulate

Leaves exstipulate

(from 596)

Herbs

Shrubs or trees

Fruit a nut

Fruit a capsule

(from 580)

Ovary or gynoecium superior
Ovary inferior

Gynoecium apocarpous
Gynoecium syncarpous or carpel 1
Leaves alternate

Leaves opposite

Perianth segments 5

Perianth segments 6

Leaves gland-dotted

Leaves not gland-dotted

Ovules 1 per carpel

Ovules 2 or more per carpel
Leaves alternate, radical, or absent
Leaves opposite

Climbers

Non-climbers

Styles 3, free

Styles connate or united, stigmas 3

Stamens 2-5 in male flowers; plants monoecious
Stamens about 8 in male flowers; plants usually

dioecious

Perianth segments 5, or perianth obscurely lobed or

truncate
Perianth segments 6
Leaves simple or absent
Leaves compound

Perianth shallow cup shaped, scarcely lobed; stamens

more or less sessile

Perianth more or less erect, clearly lobed; stamens

with filaments
(1) Style and stigma 1
(2) Styles or stigmas usually 2 or 3
(3) Styles or stigmas 8 or more

Rosaceae
Sapindaceae

Haloragaceae
613

Fagaceae
Datiscaceae

615
643

616
620

617
Monimiaceae

618
Menispermaceae

Rutaceae
619

Phytolaccaceae
Sterculiaceae

621
640

622
624

Amaranthaceae
623

Euphorbiaceae

Polygonaceae

625
637

626
635

Gyrostemonaceae

627

628
630
Phytolaccaceae

628

629

630

631

632

633

634

635

636

637

638

639

640

641

642

643

644

645

Ovary 1-locular

Ovary 3- or more-locular
Style terminal; ovule 1
Style gynobasic; ovules 2
Herbs

Shrubs or trees

Ovary 1-locular

Ovary 2- or more-locular
Ovary 1-locular with 1 ovule
Ovary 2-3-locular

Leaf base sheathing

Leaf base not sheathing
Leaves stipulate

Leaves exstipulate

Herbs

Shrubs or trees

Leaves 3-folioliate

Leaves pinnate

Slender creeping perennials
Shrubs or trees

Perianth in 2 whorls each of 3 united segments

Perianth segments usually all free

Perianth segments in 1 series; style 1, entire or

shortly lobed

Perianth segments usually in 2 series; styles usually 3,

simple or divided
(from 620)
Style 1, with 1 or 2 stigmas
Styles 2 or more
Woody climbers
Shrubs or trees
Stamens 2 in male flowers
Stamens more than 2
(from 614)
Leaves compound
Leaves simple
(1) Style and stigma 1, or stigma sessile
(2) Styles or stigmas 2
(3) Styles or stigmas 3-8
Fruit a cypsela
Fruit a schizocarp

Key to families

629
Sapindaceae

Euphorbiaceae
Surianaceae

631
632

Amaranthaceae
Euphorbiaceae
633
Euphorbiaceae

Polygonaceae
634

Ulmaceae
Chenopodiaceae

Rosaceae
636

Euphorbiaceae
Sapindaceae

Polygonaceae
638

Ebenaceae
639

Sapindaceae

Euphorbiaceae

641
Euphorbiaceae
Nyctaginaceae

642

“4
Oleaceae
Sapindaceae

Apiaceae

644
Combretaceae
645

646
Asteraceae
Apiaceae

151

Key to families

646

647

648

649

650

651

652

653

654

655

656

657

658

659

660

661

662

663

152

Fruit a nut

Fruit a capsule

(from 572)

Latex present

Latex absent

(1) Ovary 3-locular, superior

(2) Ovary 1-locular, inferior

(3) Ovary not as above

Perianth in 1 series of 4 or 5 segments
Perianth in 2 series; sepals 2; petals 4
Ovary superior

Ovary inferior

Stamens 4; trees

Stamens indefinite; mostly herbs
Ovary or gynoecium superior
Ovary inferior

Gynoecium apocarpous
Gynoecium syncarpous or carpel 1
(1) Perianth segments 2

(2) Perianth segments 4

(3) Perianth segments 5

(4) Perianth segments 6

Climbers

Non-climbers

Herbs

Shrubs or trees

Leaves radical

Leaves alternate

Perianth segments united

Perianth segments free

Leaves stipulate

Leaves exstipulate

Leaves gland-dotted

Leaves, if present, not gland-dotted

(1) Leaves all alternate, or absent

(2) Leaves radical, or radical and alternate

(3) Leaves opposite

(1) Leaves mostly radical
(2) Leaves all alternate
(3) Leaves opposite

Leaf pitchers present
Leaf pitchers absent

Fagaceae
Datiscaceae

648

652
Euphorbiaceae
Asteraceae
649

651

650
Papaveraceae
Rubiaceae
Moraceae
Papaveraceae
653

792

654

667
Winteraceae
655

660

662
Ranunculaceae
656

657

658
Ranunculaceae
Phytolaccaceae
Sterculiaceae
659
Magnoliaceae
Monimiaceae
Rutaceae

661
Phytolaccaceae
Ranunculaceae
Cunoniaceae
663

664
Monimiaceae
Cephalotaceae
Ranunculaceae

664

665

666

667

668

669

670

671

672

673

674

675

676

677

678

(1) Aquatic herbs with peltate leaves

(2) Woody climbers
(3) Shrubs or trees, non-climbers

Stamens 8
Stamens indefinite

Leaves distichous; receptacle short

Leaves not distichous; receptacle elongated

(from 653)

(1) Perianth segment 1

(2) Perianth segments 2

(3) Perianth segments 3

(4) Perianth segments 4

(5) Perianth segments 5

(6) Perianth segments 6
Stamens 5 or fewer

Stamens indefinite

Herbs or small shrubs

Trees

(1) Leaves alternate

(2) Leaves opposite or verticillate
(3) Leaves absent

Style 1

Styles 2 or 3

Tendrils present

Tendrils absent

Stigma 1

Stigmas 3

Leaves alternate, radical, or absent
Leaves opposite or verticillate
Style and stigma 1

Styles or stigmas more than 1
(1) Stamens 2

(2) Stamens 3

(3) Stamens 3, staminode 1
(4) Stamens 4

(5) Stamens 5

(6) Stamens 6

(7) Stamens more than 6
Fruit a berry

Fruit an achene

Leaves simple or absent
Leaves compound

Key to families

Cabombaceae
Menispermaceae
665
Phytolaccaceae
666

Annonaceae
Magnoliaceae

Caryophyllaceae
668

670

674

719

771
Chenopodiaceae
669
Papaveraceae
Winteraceae
671

673
Chenopodiaceae
672
Amaranthaceae
Vitaceae
Caryophyllaceae
Lythraceae
Elatinaceae

675

708

676

701

678

Rosaceae
Proteaceae

682

Rosaceae

677

695

Lauraceae
Rosaceae
679

681

153

Key to families

679

680

681

682

683

684

685

686

687

688

689

690

691

692

693

694

695

696

154

Leaves radical or absent

Leaves alternate

Herbs; perianth segments free

Shrubs; perianth segments united

Floating aquatics

Rooted land plants

Plants usually climbers with leaf-opposed tendrils

Plants without tendrils

Leaves compound

Leaves simple

Stamens epiphyllous

Stamens not epiphyllous

Fruit an achene

Fruit a legume

Leaves with stinging hairs

Leaves without stinging hairs

Stamens distinctly epiphyllous

Stamens adhering to base of perianth, or free from it

Stamens same number as and opposite perianth
segments and often sessile on them

Stamens same number as and alternate with perianth
segments, or twice as many

Flowers in axillary spikes

Flowers not in spikes

Leaves glabrous or with scattered hairs

Underside of leaves white with close-set hairs

Perianth segments united into 4-lobed floral tube

Perianth segments not united

Perianth petaloid

Perianth sepaloid

Stamens same number as and opposite perianth
segments

Stamens same number as and alternate with perianth
segments, or more numerous

Flowers ebracteate, in terminal racemes

Flowers bracteate, in clusters, cymes, or heads

(from 676)

Leaves simple

Leaves compound

Herbs

Shrubs or trees

Lentibulariaceae
680

Brassicaceae
Thymelaeaceae

Lentibulariaceae
Rosaceae

Vitaceae
683

684
686

Proteaceae
685

Rosaceae
Caesalpiniaceae

Urticaceae
687

688
689

Proteaceae

Elaeagnaceae

690
692

691
Urticaceae
Opiliaceae

Santalaceae

693
694

Proteaceae

Phytolaccaceae

Brassicaceae
Urticaceae

696
700
697
698

697

698

699

700

701

702

703

704

705

706

707

708

709

710

711

712

Sepals 2, valvate, completely enclosing bud; ovules
several in each loculus

Sepals not as above; ovule 1 in each loculus
Stamens 10 or fewer

Stamens indefinite

Leaves gland-dotted

Leaves not gland-dotted

Shrubs or trees

Herbs

(from 675)

(1) Stamens 4 or fewer

(2) Stamens 5-10

(3) Stamens indefinite

Herbs, either aquatic or growing in wet places; leaves

radical, floating or absent; sepals 2; petals united,
corolla 2-lipped

Plants not as above

Leaves with ochrea

Leaves without ochrea

Herbs or shrubs; leaves covered with mealy scales

Trees

Style 1, stigmas usually 2

Styles more than 1

Trees with irritant hairs; stipules reniform; fruit a
large drupe

Herbs without irritant hairs; stipules sheath-like; fruit
a small nut

Ovary 3- to 5-locular

Ovary 1-locular

(from 674)

Style and stigma 1

Styles or stigmas more than 1

(1) Stamens 2

(2) Stamens 3 or 5

(3) Stamens 4

(4) Stamens 8

Stamens free from perianth, united into a cup at base

Stamens adnate to perianth

Annual herbs, frequently in moist situations

Small shrubs

Leaves with stinging hairs

Leaves without stinging hairs

Key to families

Papaveraceae
Phytolaccaceae

Thymelaeaceae
699

Winteraceae
Tiliaceae

Caesalpiniaceae
Rosaceae

702
705
707

Lentibulariaceae
703

Polygonaceae
704

Chenopodiaceae
Ulmaceae

Sapindaceae
706

Davidsoniaceae

Polygonaceae

Nymphaeaceae
Papaveraceae

709

716

710
Lythraceae

712
Thymelaeaceae

“7

Amaranthaceae
711

Lythraceae
Thymelaeaceae

Urticaceae
713

155

Key to families

713

714

715

716

717

718

719

720

721

722

723

724

725

726

727

728

156

Stamens distinctly adnate to perianth

Stamens free from perianth or attached at the very
base of the perianth segments

Shrubs or trees

Herbs

Shrubs or trees

(from 708)

(1) Stamen 1

(2) Stamens 4 alternating with the perianth lobes

(3) Stamens 4, opposite the perianth lobes

(4) Stamens more than 4

Styles 2

Styles 4

Stamens indefinte

Stamens 8

(from 667)

Leaves alternate, radical, or absent

Leaves opposite or verticillate

Stamens 5 or fewer

Stamens more than 5

Style and stigma 1

Styles or stigmas more than 1

Climbers with leaf-opposed tendrils

Non-climbers, or climbers without leaf-opposed
tendrils

Leaves simple or absent

Leaves compound

Flowers in clusters of 2—4, surrounded by
conspicuous coloured bracts

Flowers not as above

(1) Stamens 2 or 3, with or without anthers, united at
base into a short cup

(2) Stamens 3; staminodes 5

(3) Stamens 5, all with anthers

Herbs or undershrubs

Shrubs or trees

Stamens alternate with perianth segments

Stamens opposite perianth segments

Ovary surrounded by nectar-secreting disc

Ovary not surrounded by nectar-secreting disc

714

715

Proteaceae
Lythraceae

Amaranthaceae
Santalaceae

Caryophyllaceae
Aizoaceae
Santalaceae

717

Cunoniaceae
718

Aizoaceae
Cunoniaceae

720
757
721
740

722
729

Vitaceae

723

724
Caesalpiniaceae

Nyctaginaceae
725

Amaranthaceae
Olacaceae

726
Amaranthaceae
727

728
Santalaceae
Rhamnaceae
Sterculiaceae

7129

730

731

732

733

734

735

736

737

738

739

740

741

742

743

744

745

(1) Tendril climbers

(2) Twiners, without tendrils

(3) Not climbers or twiners

Tendrils axillary

Tendrils terminating inflorescence

Perianth segments free; styles 3

Perianth segments united; style 1, with 2 short
stigmas

Herbs

Shrubs or trees

Ovary 1-locular, with 1-several ovules

Ovary 3—5-locular, with several ovules in each
loculus

Flowers hypogynous; calyx free, divided to base or
nearly so

Flowers perigynous; calyx entirely or partly adnate to

ovary, or free but with a distinct tube
Leaves with ochrea
Leaves without ochrea
Flowers with 1 bract and usually 1—2 bracteoles
Flowers without bracts or bracteoles
Stamens opposite perianth segments
Stamens alternating with perianth segments
Perianth segments free; tall shrubs or trees
Perianth segments united; shrubs, usually small
Stamens 5; staminodes 5; ovary 5—locular
Stamens 5; ovary 2- or 3-locular
(from 720)
Leaves simple or absent
Leaves compound
Style 1
Styles 2 or more, free
Stigma large, peltate
Stigma not peltate
Flowers in clusters of 3-5, surrounded by 3 large
coloured bracteoles
Flowers not surrounded by conspicuous bracteoles
(1) Climbers
(2) Herbs, non-climbers
(3) Shrubs or trees
Stamens 10 or fewer
Stamens indefinite

Key to families

730
731
732

Passifloraceae
Polygonaceae

Amaranthaceae

Rhamnaceae

733
737

735

734

Molluginaceae

Aizoaceae
Polygonaceae
736
Amaranthaceae
Chenopodiaceae
738

739

Ulmaceae
Chenopodiaceae

Sterculiaceae
Rhamnaceae

741
755

742
=f 752

Surianaceae
743

Nyctaginaceae
7144

Polygonaceae
745
747

746
Molluginaceae

157

Key to families

746 Flowers hypogynous
Flowers perigynous

747

748

749

750

751

752

753

754

755

756

757

758

759

760

761

762

158

Perianth segments united
Perianth segments free

Leaves absent; stems flat and green

Leaves present

Stamens 10 or fewer; stigmas 2 or 3

Stamens indefinite; stigma 1

Flowers small, in heads or spikes; stamens exserted
Flowers not in heads or spikes; stamens usually not

exserted

Seeds endospermic; stipules present, often caducous
Seeds non-endospermic; stipules absent

(1) Styles 2
(2) Styles 3
(3) Styles 5
(4) Styles about 8

Ovary 1-locular; ovule 1
Ovary 3-locular; ovules several in each loculus

Flowers hypogynous; calyx free, divided to base or

nearly so

Flowers perigynous; calyx entirely or partly adnate to
ovary, or free but with a distinct tube

(from 740)

(1) Leaves pinnate; stigma 1
(2) Leaves pinnate; stigmas 2
(3) Leaves bipinnate

Ovary 1-locular

Ovary 2— or more-locular

(from 719)

Style and stigma 1

Styles or style-branches more than |
Leaves gland-dotted

Leaves not gland-dotted

Stamens free from perianth

Stamens adnate to perianth
Perianth segments free

Perianth segments united

Opposite leaves unequal in size
Opposite leaves equal in size

Stamens 10

Stamens less than 10

Polygonaceae
Aizoaceae

748
750

Polygonaceae
749

Sapindaceae
Elaeocarpaceae

Mimosaceae

751

Flacourtiaceae
Lauraceae

Polygonaceae
753

Aizoaceae
Phytolaccaceae

Polygonaceae
754

Molluginaceae

Aizoaceae

756
Sapindaceae
Mimosaceae

Caesalpiniaceae
Sapindaceae

758

763

Myrtaceae

7159

760

761
Amaranthaceae
Nyctaginaceae
Aizoaceae

762
Thymelaeaceae
Lythraceae

7163

7164

765

766

7167

768

769

770

771

7712

773

774

715

776

7717

778

7719

780

(1) Stamen 1

(2) Stamens 2-5

(3) Stamens more than 5
Stamens free from perianth
Stamens adnate to perianth
Ovule 1

Ovules more than 1

Placentation free-central
Placentation axile

Perianth segments scarious
Perianth segments herbaceous

Flowers hypogynous

Flowers perigynous; stamens borne on calyx-tube

Herbs
Shrubs or trees

Ovary 1-locular; leaves opposite or verticillate

Ovary 3-5-locular; leaves alternate, often clustered in

axils so as to appear verticillate
(from 667)
Leaves alternate, radical, or absent
Leaves opposite or verticillate
Sepals 2, often caducous; petals 4
Perianth in 1 series or, if in 2 series, usually of
3 + 3 segments
Flowers actinomorphic; stamens numerous
Flowers zygomorphic; stamens 6
(1) Stamens 3
(2) Stamens 5 or 6, sometimes with staminodes
(3) Stamens more than 6
Trees or shrubs
Climbers with leaf-opposed tendrils
Style and stigma 1
Styles 2-3
Plants without tendrils
Climbers with leaf-opposed tendrils
Leaves large, compound
Leaves simple
Perianth segments free
Perianth segments united
Leaves with ochrea
Leaves without ochrea

Key to families

Caryophyllaceae
7164
768

765

Aizoaceae

767

766
Caryophyllaceae
Molluginaceae

Amaranthaceae
Chenopodiaceae

769
Aizoaceae

770
Cunoniaceae

Caryophyllaceae

Aizoaceae

7712
787
773

7174
Papaveraceae
Fumariaceae
775

777

781

776
Vitaceae

Lauraceae
Euphorbiaceae
778

Vitaceae

Burseraceae
7179

780
Ebenaceae

Polygonaceae
Euphorbiaceae

159

Key to families

781

782

783

784

785

786

787

788

789

790

791

792

793

794

795

796

797

798

160

Leafless parasitic twiners
Non-twiners

Style and stigma 1

Styles or stigmas 2-3

Flowers with 1 or more long spurs
Flowers lacking spurs

Ovary 1-locular

Ovary 2- or more-locular

Leaves gland-dotted

Leaves not gland-dotted

Perianth segments free

Perianth segments united

(from 771)

(1) Stamens 3

(2) Stamens 9, usually with 3 staminodes
(3) Stamens 10 or indefinite
Woody climbers

Non-climbers

Leaves trifoliolate

Leaves not trifoliolate

Herbs

Shrubs or small trees

Carpels 2

Carpels 4-15

(from 652)

Plants parasitic (mistletoes)

Plants not parasitic

Leaves alternate, radical, or absent
Leaves opposite or verticillate
Leaves gland-dotted

Leaves not gland-dotted, or leaves absent
Stamens 10

Stamens indefinite

Perianth actinomorphic

Perianth zygomorphic

(1) Perianth quite entire, or of 3 segments
(2) Perianth segments 4

(3) Perianth segments 5 or 6

(1) Stamens 2

(2) Stamens 4

(3) Stamens 5

(4) Stamens 6 or more

Lauraceae

782

783

786
Ranunculaceae
784

Lauraceae

785

Rutaceae
Elaeocarpaceae
Polygonaceae
Ebenaceae

Elatinaceae
Lauraceae
788
Monimiaceae
789
Cunoniaceae
790
Lythraceae
791
Aquifoliaceae
Sonneratiaceae

Loranthaceae
793

794

809

795

796
Combretaceae
Myrtaceae
797

808
Aristolochiaceae
798

800
Gunneraceae
799
Asteraceae
Aizoaceae

799

800

801

802

803

804

805

806

807

808

809

810

811

812

813

814

815

(1) Flowers in umbels

(2) Flowers in heads surrounded by involucral bracts
(3) Flowers not in umbels or heads
Stamens 5

Stamens more than 5

Anthers free

Anthers united around style

Herbs

Shrubs or trees

Style 1, with 1-2 stigmas

Styles 2, free

Stamens opposite perianth segments
Stamens alternating with perianth segments
Leaves simple and entire

Leaves compound or dissected

Leaves simple

Leaves compound

Trees; stamens usually 10

Herbs or shrubs; stamens usually indefinite
(from 796)

Stigmas 1 or 2, each with indusium
Stigmas 3-6, without indusium

(from 793)

Leaves gland-dotted

Leaves not gland-dotted

(1) Perianth segments 3

(2) Perianth segments 4

(3) Perianth segments 5

(4) Perianth segments 6

(1) Stamens 2

(2) Stamens 4; anthers not syngenesious
(3) Stamens 4-5; anthers syngenesious
(4) Stamens 8

(5) Stamens indefinite

Leaves simple

Leaves compound or unifoliolate
Aquatic herbs

Plants not aquatic

Leaves opposite

Leaves in whorls of 4-8

Stamens alternating with perianth segments
Stamens opposite perianth segments

Key to families

Araliaceae
Asteraceae
Santalaceae
801

806

802
Asteraceae
Apiaceae
803

804
Araliaceae
Santalaceae
805
Rhamnaceae
Araliaceae
807
Araliaceae
Combretaceae
Aizoaceae

Goodeniaceae
Aristolochiaceae

Myrtaceae
810

Rubiaceae

811

816

818
Thymelaeaceae
PP 813
Asteraceae
Cunoniaceae
812
Myrtaceae
Flacourtiaceae
Haloragaceae
814

815

Rubiaceae
Rubiaceae
Santalaceae

161

Key to families

816

817

818

819

820

821

822

823

824

825

826

827

828

829

830

831

832

833

162

(1) Stamens 1

(2) Stamens 5

(3) Stamens indefinite

(1) Anthers syngenesious

(2) Anthers free, opposite perianth segments

(3) Anthers free, alternating with perianth segments

Leaves simple

Leaves compound

(1) Stamens 3

(2) Stamens 10

(3) Stamens indefinite

(from 2)

Latex present

Latex absent

Styles or stigmas 3 or more

Style or stigma 1

Succulent herbs 5-10 cm high, parasitic on roots;
leaves absent or scale-like

Plants not parasitic; leaves green if present

Flowers mostly unisexual

Flowers mostly bisexual

Climbers or twiners

Non-climbers

Placentation apical

Placentation basal

Leaves alternate

Leaves opposite

Leaves in whorls of 4 or more, or reduced to scales

Leaves not as above

Aquatic herbs, usually non-littoral; seeds endospermic

Littoral shrubs; seeds non-endospermic

Shrubs or trees; leaves reduced to minute scales

Aquatic herbs; leaves entire or divided but not
reduced to scales

Plants monoecious

Plants dioecious

Herbs or undershrubs; flowers in heads

Trees; flowers otherwise

Leaves serrate-crenate; deciduous

Leaves entire; evergreen

Leaves not dissected

Leaves palmately dissected

Valerianaceae
817

Aizoaceae
Asteraceae
Santalaceae
Rubiaceae

819
Caprifoliaceae
Rubiaceae
Portulacaceae
Sonneratiaceae

821

822
Euphorbiaceae
Moraceae

Balanophoraceae
823

824

836

825

826
Cannabaceae
Piperaceae

827

828

829

830
Callitrichaceae
Bataceae

Casuarinaceae

Haloragaceae
831

833
Asteraceae
832
Betulaceae
Euphorbiaceae

834
Cannabaceae

834

835

836

837

838

839

840

841

842

843

844

845

846

847

848

Both male and female flowers in dense spikes

Female flowers solitary or racemose; male flowers
solitary or in spikes

Male flowers in catkins; female flowers with
involucre of bracts but no perianth

Male flowers solitary or in open spikes; perianth
shallow cup-shaped, inconspicuous

(from 823)

Herbaceous plants, growing only on rocks in running

water
Land plants
Stamens 10 or fewer, usually 2-3
Stamens indefinite

Monocotyledons
(from 1)
Plants of marine or brackish habitats
Plants of fresh-water or land habitats
Leaves ligulate
Leaves eligulate
Plants of brackish habitats
Marine plants
Leaf blade and sheath shed leaving a circular scar
Leaf blade shed but sheath persistent and fibrous
Leaves with 1-5 longitudinal veins
Leaves with 7 or more longitudinal veins
Leaves 1-3 per shoot
Leaves 4 or more per shoot
Carpel solitary; stigmas 2, filiform
Carpels 4-8; stigma 1, peltate

Floating plants with one or more flat, leaf-like stems

1-8 mm in diameter, cohering by their edges,
with or without roots hanging from the
undersurface

Plants not as above

Flowers unisexual
Flowers bisexual

Leaves opposite or. verticillate

Leaves alternate, radical, crowded at apex of stem, or

absent

Slender, twining land plants
Aquatic or marsh plants

Key to families
Salicaceae

835

Balanopaceae

Gyrostemonaceae

Podostemaceae
837

Piperaceae
Mimosaceae

839
845

840
842

Zannichelliaceae
841

Cymodoceaceae
Posidoniaceae

843
Hydrocharitaceae

Hydrocharitaceae
844

Zosteraceae
Ruppiaceae

Lemnaceae
846

847
869

848

850

Dioscoreaceae
849

163

Key to families

849

850

851

852

853

854

855

856

857

858

859

860

861

862

863

864

865

164

Perianth in male flowers absent or of one segment

Perianth segments in male flowers 3 + 3; stamens
3-9

Leaves simple

Leaves compound

Flowers closely packed in a dense, simple,

unbranched spadix, with a usually convolute,
coloured, or petal-like spathe arising from base

Spathe sometimes present, but inflorescence not as
above and often branched

Trees or shrubs, rarely climbers; aerial stem woody

Herbs (sometimes large, e.g. banana)

Perianth absent; trees, shrubs, or climbers

Perianth segments 3 + 3; climbers

Flowers inconspicuous, often minute, within
imbricate bracts or scales, in heads or spikelets;

perianth absent or of 1-8 scales or bristles, usually
concealed within bracts

Flowers otherwise
Flowers small in spherical androgynous heads 2-8

mm in diameter without conspicuous bracts;
mostly marsh or aquatic plants

Flowers in spikelets surrounded by glume-like bracts
Leaf-sheath with free margins, sometimes overlapping
Leaf-sheath with connate margins
Leaves ligulate

Leaves eligulate

Wiry plants with jointed stems

Tiny, slender plants without erect stems
Aquatic or marsh plants

Land plants

Ovary inferior

Ovary superior

Plants dioecious

Plants monoecious

Flowers in cylindrical, terminal spikes
Flowers in globular, lateral heads
Climbers

Non-climbers

Ovary superior

Ovary inferior

Ovary superior

Ovary inferior

Najadaceae

Hydrocharitaceae

851
868

Araceae

852

853

854
Pandanaceae
Smilacaceae

855
859

Eriocaulaceae
856

857
Cyperaceae
Poaceae

858
Restionaceae
Hydatellaceae
860

863
Hydrocharitaceae
861
Hanguanaceae
862
Typhaceae
Sparganiaceae
864

865
Smilacaceae
Dioscoreaceae
866

Musaceae

866

867

868

869

870

871

872

873

874

875

876

877

878

879

880

Leaves large, pinnately or palmately divided (palms)

Leaves otherwise

(1) Fruit containing many small seeds

(2) Fruit containing 3 large seeds

(3) Fruit a fleshy, thick-walled, 1-3-seeded drupe;
leaves with many cross-nerves

(from 850)

Ovary superior

Ovary inferior

(from 846)

Flowers closely packed in a simple spadix, usually
with coloured spathe more or less enclosing it

Flowers not in spadix; inflorescence often branched;
spathe sometimes present

Gynoecium apocarpous

Gynoecium syncarpous or carpel 1

Land plants

Aquatic or marsh plants

Woody plants; leaves compound, or pinnately or
palmately divided (palms)

Small herbaceous plants; leaves, if present, entire

Saprophyte, lacking chlorophyll; leaves reduced to
scales

Tufted chlorophyllous herbs; leaves linear

(1) Perianth segments 2; stamens 6; carpels 3

(2) Perianth segments 4; stamens 4; carpels 4

(3) Perianth segments 3-6, rarely 4; stamens
3-indefinite; carpels 3-indefinite

Perianth segments all similar in texture and colour

The two perianth whorls different in texture and/or
colour

Gynoecium of 3 or more free carpels; fruits achenes

Gynoecium of about 6 free carpels; fruits follicles

Ovary superior or perianth absent

Ovary inferior

Flowers inconspicuous, often minute, within
imbricate bracts or scales (glumes), in spikelets;
perianth absent or of 1-8 scales or bristles, usually
concealed within bracts

Flowers otherwise

Leaves ligulate

Leaves eligulate

Embryo visible through fruit wall
Embryo not visible through fruit wall

Key to families

Arecaceae
867

Juncaceae
Liliaceae

Hanguanaceae

Arecaceae
Dioscoreaceae

Araceae

870

871
877

872
874

Arecaceae
873

Triuridaceae
Centrolepidaceae

Aponogetonaceae
Potamogetonaceae

875

Juncaginaceae

876

Alismataceae
Limnochdritaceae
878

909

879
883

880
881

Poaceae
Cyperaceae

165

Key to families

881

882

883

884

885

886

887

888

889

890

891

892

893

894

895

896

897

898

166

Stamen 1

Stamens more than one

Small annuals; inflorescence simple

Rhizomatous perennials; inflorescence usually
branched

Perianth segments 4 or fewer

Perianth segments 6 (rarely 5)

(1) Stamen 1

(2) Stamens 3

(3) Stamens 4

Leaves alternate; twiners

Leaves radical; inflorescence spicate

Leaves simple or absent

Leaves compound (palms)

Stems woody; leaves broad (palms)

Not as above

Stamens 3 (rarely 2)

Stamens 6 (rarely 5)

Inner perianth segments free

Inner perianth segments united

Perianth segments all similar in texture and colour

The two perianth whorls different in texture and/or
colour

Stamens free from perianth

Stamens inserted at base of inner perianth segments

Perianth segments petaloid

Perianth segments sepaloid

Carpels free or almost free; stigmas sessile

Carpels fused; style one, stigmas 3

Leaf tips prolonged into tendrils

Not as above

Corolla about 3 mm long

Corolla about 10 mm long

Perianth segments all similar in texture and colour

The two perianth whorls different in texture and/or
colour

Much-branched leafy climbers

Rosette or scrambling plants

Inflorescence spicate; glandular hairs present

Flowers solitary or inflorescence cymose; if spicate
no glandular hairs

882
Cyperaceae

Centrolepidaceae

Cyperaceae
884
886

Philydraceae
Xyridaceae
885

Stemonaceae
Araceae

887
Arecaceae

Arecaceae
888

889
894

890
Xyridaceae

891

Commelinaceae

892
Haemodoraceae

Liliaceae
893

Juncaginaceae
Juncaceae

895
896

Flagellariaceae
Liliaceae

900

897

Smilacaceae
898
Commelinaceae

899

900

901

902

903

904

905

906

907

908

909

910

911

912

913

914

915

Inner perianth segments fringed

Inner perianth segments not fringed

Perianth segments petaloid

Perianth segments sepaloid

Aquatic plants, floating or rooted

Land plants

Coarse woody climbers; venation predominantly
reticulate

Non-climbers or, if climbers, the venation convergent

Inflorescence a tall woody spike

Inflorescence otherwise

Much-branched leafy climbers

Not as above

Marsh or aquatic plants

Land plants

Climbers

Non-climbers

Style 1, simple

Style branched, stigmas 3

Inflorescence a tall woody spike

Inflorescence otherwise

(from 877)

(1) Flowers strongly gynandrous

(2) Flowers only weakly gynandrous

(3) Flowers not gynandrous

Venation pinnate

Venation convergent

Submerged aquatics; leaf lamina submerged or
floating; styles or stigmas 6, each 2—lobed

Not as above

Leaves entire or with serrate margins

Leaf lamina deeply dissected

Climbing plants; leaves alternate with many
longitudinal veins from midrib; veinlets reticulate

Not as above

Venation obviously pinnate

Venation convergent (middle vein sometimes stronger
than others) parallel, or obscured by the thickness
of leaf

Stamens 1-3

Stamens 5

Key to families

Liliaceae
Commelinaceae

901
905

Pontederiaceae
902

Smilacaceae
903

Xanthorrhoeaceae
904

Smilacaceae
Liliaceae

Juncaginaceae
906

Araceae
907

908
Juncaceae

Xanthorrhoeaceae
Liliaceae

Orchidaceae
910
911

Cannaceae
Orchidaceae

Hydrocharitaceae
912

a 913
Taccaceae

Smilacaceae
914

915

919
916
Musaceae

167

Key to families

916

917

918

919

920

921

922

923

924

925

926

927

928

168

Ligule present at junction of leaf-sheath and lamina

Leaves eligulate

Leaves 2-ranked

Leaves more than 2-ranked

Pulvinus present at junction of petiole (or leaf-sheath)
and blade

Pulvinus absent

Stamens 3

Stamens 6

Perianth segments united at base

Perianth segments free

Anthers with transverse dehiscence

Anthers with longitudinal dehiscence

Ovules 1-2 per loculus

Ovules usually several per loculus

Plant a colourless saprophyte

Plant chlorophyllous

Perianth actinomorphic

Perianth zygomorphic

Leaf margins entire

Leaf margins serrate

Perianth segments all similar in texture and colour

The two perianth whorls different in texture and/or
colour

Flowers in umbels, rarely solitary on a leafless scape

Flowers in simple or compound racemes

Leaves narrow, up to 20 cm long, arising from an
underground rhizome

Leaves thick, fibrous, up to 2 m long, in tufts at base
or apex of trunk-like stem

917

918
Zingiberaceae
Costaceae

Marantaceae
Cannaceae

920
923

921
922

Burmanniaceae
Iridaceae

Haemodoraceae
Iridaceae

924
925

Burmanniaceae
Corsiaceae

926
Bromeliaceae

927

Bromeliaceae

Liliaceae
928

Liliaceae

Agavaceae

GLOSSARY

Alison McCusker

This general glossary contains terms likely to be used frequently in the volumes of
the Flora dealing with vascular plants. Specialised terms that are crucial to the
understanding of individual family accounts, but not of wide application, will be
explained and illustrated, where appropriate, in the relevant volumes.

Separate glossaries will be included in volumes dealing with the non-vascular
groups (Volume 49ff.). However, where a word in the general glossary has a different
application to non-vascular plants, its meaning in that context is included here.

It is the policy of the Editorial Committee to keep the use of technical terms
within reasonable bounds so as to make it as easy as possible for the reader to con—
sult the Flora without constant reference to the glossary. Simple explanations have
been preferred to long and involved ones; the meanings given are believed to be
accurate but are certainly not claimed to be complete. Words explained adequately,
for botanical purposes, in The Concise Oxford Dictionary have generally not been
included unless much more widely used in English in a different sense.

The glossary is also intended to guide the contributors to the Flora, who will
number many before the project is completed, in the use of terminology. For that
reason alternative spellings that are commonly used in the taxonomic literature are
often not given. ?

abaxial: of the side or surface of an organ, facing away from the axis. cf. adaxial.

abscission: the normal shedding from a plant of an organ that is mature or aged,
e.g. a ripe fruit, an old leaf. adj. abscissile.

accessory fruit: a fruit, or group of fruits derived from one flower, in which the con—
spicuous, fleshy portion develops from the receptacle and is shed with the true
fruit(s) attached.

accumbent: of the orientation of an embryo, with the radicle lying against the edges —
of the two cotyledons.

achene: a dry, indehiscent fruit formed from a superior ovary of one carpel and con—
taining one seed which is free from the pericarp (often applied, less correctly, to
the one-seeded fruits of Asteraceae). cf. cypsela.

acicular: needle-shaped and stiff. Fig. 23.

aciculate: finely scored on the surface, as if scratched by a pin.

acropetal: arising or developing in a longitudinal sequence beginning at the base and
proceeding towards the apex. cf. basipetal.

acrostichoid: of sporangia, densely covering the abaxial surface of the fertile frond,
i.e. not in distinct groups; of ferns, having the sporangia arranged as above.

actinomorphic: of flowers, symmetrical about more than one vertical plane. cf. zygo—
morphic.

acuminate: tapering gradually to a protracted point. Fig. 23.

acute: terminating in a distinct but not protracted point, the converging edges sepa—
rated by an angle less than 90 degrees. Fig. 23.

adaxial: facing towards the axis. cf. abaxial.

169

Glossary

adnate: fused to an organ of a different kind, e.g. applied to a stamen fused to a
petal.

adventitious: arising in abnormal positions, e.g. roots arising from the shoot system,
buds arising elsewhere than in axils of leaves.

adventive: introduced recently, in particular since colonisation by man.

aerenchyma: tissue incorporating large, gas-filled spaces interspersed with the cells in
a characteristic pattern.

aestivation: the arrangement of sepals and petals or their lobes in an unexpanded
flower bud. cf. vernation. Fig. 25.

aggregate fruit: a cluster of fruits formed from the free carpels of one flower.

albumen: = endosperm.

allopatric: of two or more species, having different ranges of distribution. cf. sym—-
patric.

alternate: of Jeaves or other J/ateral organs, borne singly at different heights on the
axis; of floral parts, on a different radius, e.g. describing the position of stamens
with respect to petals.

anastomosis: fusion to form a network e.g. of veins in a leaf blade.

anatropous: of an ovule, inverted so that the micropyle faces the placenta. Fig. 25.

androdioecious: having bisexual flowers and male flowers, on separate plants.

androecium: the stamens of one flower collectively.

androgynophore: a stalk bearing both the androecium and gynoecium of a flower
above the level of insertion of the perianth.

androgynous: having male and female flowers in the same inflorescence.
androphore: a stalk bearing the androecium.
anemophilous: pollinated by wind.

angiosperm: a seed-bearing plant whose ovules, and hence seeds, develop within an
enclosed ovary. cf. gymnosperm.

annual: a plant whose life span ends within one year after germination.
annular: arranged in or forming a ring.

annulus: a ring; in ferns, the elastic ring of cells, forming part of the sporangium wall,
that initiates dehiscence.

anterior: of floral organs, on the side of the flower farthest from the axis. cf. pos—
terior.

anther: the pollen-bearing part of a stamen. cf. filament.

antheridium: the fertile organ of a male gametophyte or the male organ of a bisexual
gametophyte, in which male gametes are formed.

anthesis: the time of opening of a flower.

anthocarp: a false fruit consisting of the true fruit and the base of the perianth, as in
Nyctaginaceae.

antrorse: directed forwards or upwards. cf. retrorse.

apetalous: without petals.

apical: of a placenta, at the top of the ovary. Fig. 25.

apiculate: terminating in a short, sharp, flexible point. Fig. 23.

apocarpous: of a gynoecium, consisting of two or more carpels which are free from
one another or almost so.

apomict: a plant that produces viable seed without fertilisation.

170

Glossary

appendage: a structure arising from the surface or extending beyond the tip of
another structure.

appressed: pressed closely against but not united with.

aquatic: living in or on water for all or a substantial part of the life span (generally
restricted to fresh/inland waters).

arborescent: resembling a tree (applied to non-woody plants attaining tree height and
to shrubs tending to become tree-like in size). cf. dendroid.

areole: a space between the threads of a net; in Cactaceae, a cluster of hairs/
spines/bristles borne at the node of a leafless stem; in Mimosaceae (for example),
a distinct, oblong or elliptical area on the face of a seed, bounded by a fine line.
adj. areolate.

aril: a structure partly or wholly covering the testa of a seed and formed by expan—
sion of the funicle. adj. arillate.

aristate: having a stiff, bristle-like awn or tip. Fig. 23.

aristulate: having a small awn.

article: a segment of a jointed stem or of a fruit with constrictions between the seeds.

articulate: jointed; having joints where separation may occur naturally; of a stem,
having nodes.

ascending: growing erect after an oblique or semi-horizontal beginning.

asexual: not forming part of a cycle which involves fertilisation and meiosis.

attenuate: tapering gradually.

auricle: an ear-shaped appendage at the base of a leaf, leaflet or corolla lobe. adj.
auriculate. Fig. 23.

autochthonous: of the inhabitants of a region, original; earliest known; (applied to an
element of the Australian flora rich in endemics and believed to have been evol—
ving in Australia for a long period of time).

autotrophic: independent of other organisms in respect of organic nutrition; able to
fix carbon dioxide, by photosynthesis, to form carbohydrates.

awn: a bristle-like appendage, e.g. on the tip or back of the lemma of a grass floret.

axil: the angle between a leaf or bract and the axis bearing it. adj. axillary.

axile: on an axis; of a placenta, on the central axis of the ovary. Fig. 25.

axis: a stem, (commonly used for the main stem of a whole plant or of an
inflorescence).

barbellae: short, straight, stiff hairs or barbs.

basal: at the base; of a placenta, at the base of the ovary. Fig. 25. w~

basifixed: attached at or by the base, e.g. of anthers, by the base of the connective.

basipetal: developing, in sequence, from the apex towards the base. cf. acropetal.

basiscopic: pointing towards the base (applied to the first lateral vein of a leaflet on
the side nearer the leaf base).

beak: a prominent terminal projection, especially of a carpel or fruit.

berry: a fleshy or pulpy indehiscent fruit with the seed(s) embedded in the fleshy
tissue of the pericarp. cf. drupe.

biennial: a plant whose life span extends for more than one but less than two years
after germination.

bifid: divided, for about half the length, into two parts. cf. bipartite.

bifoliate: of plants, having two leaves.

bifoliolate: of /eaves, having two leaflets.

171

Glossary

bilabiate: two-lipped, e.g. of a corolla in which fusion of an anterior group and a
posterior group of petals extends beyond the top of the corolla tube.

bilocular: having two cavities.

bipartite: divided, nearly to the base, into two parts. cf. bifid.

bipinnate: of Jeaves, twice pinnately divided. Fig. 24.

biseriate: arranged in two rows or whorls.

bisexual: bearing both male and female organs together, e.g. on the same gameto-—
phyte or in the same flower.

blade: the expanded part of a leaf or petal.

bole: the trunk of a tree, below the lowest branch. cf. canopy.

bract: a leaf-like structure, different in form from the foliage leaves and without an
axillary bud, associated with an inflorescence or flower.

bracteole: a small bract-like structure borne singly or in pairs on the pedicel or calyx
of a flower.

bulb: a storage organ, usually underground, made up of a stem and leaf bases, the
food reserves being stored in the inner, fleshy leaf bases.

bulbel: a bulb arising from another bulb.

bulbil: a small, deciduous bulb (or tuber) formed in the axil of a leaf and functioning
to propagate the plant vegetatively.

burr: a rough or prickly propagule consisting of a seed or fruit and associated floral
parts or bracts.

buttress: a flange of tissue protruding from the main outline of the base of a tree.

caducous: falling off early.

caespitose: growing in tufts.

callus: a protruding mass of hardened tissue, often formed after an injury but some—
times a regular feature of the plant, e.g. on the labellum of some orchids and the
axis of the spikelet of some grasses. adj. callose.

calyptra: in mosses, a cap-like structure covering or partly covering the capsule and
derived from the neck of the archegonium; in a flower, (= operculum), a cap
covering the stamens and carpels in the bud and formed by fusion or cohesion of
perianth parts.

calyx: the sepals of one flower collectively.

calyx-tube: a tube formed by fusion or cohesion of sepals. cf. hypanthium.

campanulate: bell-shaped.

campylotropous: of an ovule, orientated transversely, i.e. with its axis at right angles
to its stalk, and with a curved embryo sac. Fig. 25.

canopy: the branches and foliage of a tree. cf. bole.

capitate: of an inflorescence, with the flowers unstalked and aggregated into a dense
cluster; of a stigma, globose, like the head of a pin.

capitulum: a dense cluster of sessile flowers.

capsule: a dry fruit formed from two or more united carpels and dehiscing at mat—
urity to release the seeds.

carpel: an organ (generally believed to be a modified foliar unit) at the centre of a
flower, bearing one or more ovules and having its margins fused together or with
other carpels to enclose the ovule(s) in an ovary, and consisting also of a stigma
and usually a style.

carpophore: in ferns, the stalk of a sporocarp; in a fruit, the stalk of a mericarp.

172

Glossary

caruncle (= strophiole): an outgrowth of a seed coat, near the hilum.

caryopsis: a dry, indehiscent, one-seeded fruit in which the seed coat is closely fused
to the fruit wall (characteristic of grasses).

cataphyll: a scale leaf associated with a vegetative part of a plant, e.g. rhizome,
perennating bud.

catkin: a spike in which the flowers are unisexual and without conspicuous perianth.

caudate: having a narrow tail-like appendage. Fig. 23.

caudex: a thick, erect trunk, especially of cycads.

caudicle: a thread to which a pollen mass is attached in Orchidaceae and Asclep—
iadaceae.

cauliflorous: see cauline.

cauline: of /Jeaves, borne on an aerial stem; of flowers or fruits, borne on old wood
(= cauliflorous).

cell: the basic unit of plant structure consisting, at least when young, of a protoplast
surrounded by a wall.

centrifugal: directed, or developing, from the centre or axis outwards.

centripetal: directed, or developing, from the outside towards the centre or axis.

chaff: thin, membranous scales or bracts; thin, dry unfertilised ovules among the fully
developed seeds of a fruit.

chalaza: the part of an ovule to which the end of the stalk (funicle) is attached.

chlorophyll: pigment(s) constituting the green col OULIDE matter of plants and
absorbing radiant energy in photosynthesis. ;

chromosome: a thread-like structure in the nucleus of a cell, containing a linear se—
quence of genes.

cilia: in unicellular plants, gametes, spores etc., minute hair-like protoplasmic protru—
sions whose movement confers motility on the cell; in higher plants, hairs more
or less confined to the margins of an organ. sing. cilium; adj. ciliate.

cincinnus: a spirally curled cymose inflorescence.

circinnate (= circinate): spirally coiled, with the tip innermost.

circumsciss: (to) break open along a transverse line around the circumference. adj.
circumscissile.

cladode: the photosynthetic stem of a plant whose foliage leaves are absent or much
reduced. cf. phyllode.

cladophyll: a flattened, leaf-like photosynthetic stem not bearing leaves or scales.
cf. phylloclade. SF;

class: a major taxonomic rank, between order and division.

clavate: club-shaped.

claw: a narrow, stalk-like basal portion of a petal, sepal or bract.

cleistogamous: of flowers, self-pollinating and setting fertile seed but never opening.

clone: a set of organisms produced from one parent by vegetative reproduction.

coccus: one of the (usually 1-seeded) lobes of a distinctly lobed fruit, becoming
separate at maturity. pl. cocci.

cochlear: of the arrangement of corolla lobes in a bud, a variant of imbricate aes—
tivation. Fig. 25.

cochleate: coiled like a snail-shell.

cohesion: the sticking together of floral parts of the same whorl without organic
fusion. adj. coherent.

173

Glossary

collateral: situated side by side; adjacent and on the same radius of an axis.

columella: the central axis of a moss capsule; sometimes applied to the central axis of
fruits and cones.

column: the lower part of an awn in grasses, when distinctly different in form from
the upper part; (=gynostemium), a structure in Orchidaceae, Asclepiadaceae and
Stylidiaceae, extending above the ovary of a flower and incorporating stigma, style
and stamens.

coma: a tuft of hairs. adj. comose.
commissure: a join or seam; the interfacing of two fused carpels in an ovary.

compound: of a /eaf, having the blade divided into two or more distinct leaflets; of an
inflorescence, made up of an aggregate of smaller inflorescences.

compressed: flattened in one plane, either dorsally (bringing the front and back closer
together) or laterally (bringing the sides closer together).

conduplicate: folded together, with the fold-line along the long axis (e.g. of coty—
Jedons in a seed).

cone: in gymnosperms and club-mosses, a group of sporophylls arranged compactly
on a central axis; (loosely) in Casuarina, a woody multiple fruit incorporating the
bracts and bracteoles associated with the flowers.

connate: fused to another organ (or other organs) of the same kind.
connective: the part of an anther that connects the lobes.
connivent: coming into contact; converging.

contorted: see conyolute.

convolute: of the arrangement of corolla lobes in a bud, a form of imbricate aestiva—
tion in which each segment has one edge overlapping the adjacent segment, like a
furled umbrella. Fig. 25.

cordate: of a leaf blade, broad and notched at the base; heart-shaped. Fig. 23.

corm: a fleshy, swollen stem base, usually underground, in which food reserves are
stored between growing seasons.

corolla: the petals of a flower collectively.

corona: a ring of tissue arising from the corolla or perianth of a flower and standing
between the perianth lobes and the stamens.

cortex: the region of a stem or root surrounding the vascular cylinder but inside the
epidermis.

corymb: a racemose inflorescence in which the pedicels of the lower flowers are

longer than those of the flowers above, bringing all flowers to about the same
level.

cotyledon: the primary leaf (or one of two or more primary leaves) of an embryo.
crenate: with small, rounded teeth; scalloped. Fig. 24.

crenulate: minutely scalloped. Fig. 24.

crown: the part of a tree or shrub above the level of the lowest branch.
crustaceous: brittle; of marine algae, encrusted with calcium carbonate.

cryptogam: (literally) a plant whose sexual reproductive parts are not conspicuous; a
plant that produces spores, not seeds, in its sexual reproductive cycle, e.g. ferns,
mosses, algae. cf. phanerogam.

culm: an aerial stem, in grasses, sedges, rushes, etc., bearing the inflorescence.
cuneate: wedge-shaped. Fig. 23.
cuspidate: tapering into a sharp, rigid point. Fig. 23.

174

Glossary

cyathium: an inflorescence of unisexual flowers surrounded by involucral bracts, as in
Euphorbia.

cyclic: of floral organs, several borne at the same level on the axis; whorled.
cf. spiral.

cyme: an inflorescence in which each flower, in turn, is formed at the tip of a grow—
ing axis and further flowers are formed on branches arising below it.

cypsela: a dry, indehiscent, one-seeded fruit formed from an inferior ovary.

cystolith: a stalked structure growing from a cell wall into the cell cavity, encrusted
with calcium carbonate.

deciduous: falling seasonally, e.g. of the leaves or bark of some trees.

decompound: more than once compound.

decumbent: spreading horizontally but then growing upwards.

decurrent: extending downwards beyond the point of insertion, e.g. of a lamina ex—
tending downwards to form a flange along the petiole.

decussate: in pairs, with successive pairs borne at right angles to each other.

definite: of a constant number; of stamens, twice as many as the petals or sepals, or
less; of an inflorescence, ending in a flower or an aborted floral bud.

deflexed: bent downwards.

dehiscent: breaking open at maturity to release the contents.

deltoid: triangular with the sides of about equal length. Fig. 23.

dendroid: tree-like in form but not in size.

dentate: toothed. Fig. 24.

denticulate: finely toothed. Fig. 24.

depressed: flattened as if pressed down from the top or end.

determinate: of growth or branching, with a bud or flower ‘terminating the growth of
the main axis; of an inflorescence, see definite.

diadelphous: having the stamens united into two groups, or all but one united in a
group and one free.

dichasium: a cymose inflorescence with opposite branching below the flower which
terminates each axis. cf. monochasium.

dichotomous: forking into two equal branches resulting from division of the growing *
point.

diclinous: having the stamens and the carpels in separate flowers.

dicotyledon: a flowering plant whose embryo has two (rarely more) cotyledons (seed
leaves). cf. monocotyledon. a

didymous: borne in pairs; of anthers, having two lobes, with scarcely any tissue con—
necting them.

didynamous: of stamens, four in number, two being distinctly longer than the other
two.

digitate: branching from the axis or stalk like the fingers of a hand. Fig. 24.

dimorphic: of two different forms.

dioecious: having the male and female reproductive structures on separate plants.
cf. monoecious.

diploid: having two of the basic sets of chromosomes in the nucleus. cf. haploid,
polyploid.

disc: a plate or rim of tissue, derived from the receptacle of a flower, occurring
between whorls of floral parts.

175

Glossary

dissepiment: a partition (septum) within an ovary or fruit, derived by fusion of
adjacent carpels.

distal: remote from the point of origin or attachment. cf. proximal.

distichous: arranged in two rows on opposite sides of a stem and thus in the same
plane.

diurnal: of flowers, opening only during daylight hours.

divaricate: widely spreading.

division: the major taxonomic rank within the Plant Kingdom (in which the phylum
is no longer generally recognised).

dorsal: of a Jateral organ, (relating to the side) facing away from the axis, i.e. the
‘back’; of a thallus, facing away from the substratum. cf. ventral.

dorsifixed: attached at or by the back.

dorsiventral: having structurally different upper and lower surfaces.

drupe: a succulent fruit formed from one carpel, having the seed(s) enclosed in an

inner stony layer of the fruit wall. adj. drupaceous (which is often used to mean
drupe-like but not strictly a drupe).

echinate: bearing stiff, stout, prickly hairs.
edaphic: pertaining to the soil.
elater: an elongated, spirally thickened, hygroscopic cell in the capsule of a liverwort,

derived from sporogenous tissue and assisting in spore dispersal; an appendage to
the spore of Equisetum.

elliptic: oval in outline, widest at the centre. Fig. 23.

emarginate: having a broad, shallow notch at the apex. Fig. 23.

embryo: a young plant contained within an archegonium or seed.

enation: an epidermal outgrowth.

endemic: having a natural distribution confined to a particular geographical region.

endocarp: the innermost layer of the wall of a fruit; in a drupe, the stony layer sur—
rounding the seed.

endosperm: nutritive tissue in a seed, in angiosperms triploid and formed in the
embryo sac after fertilisation, in gymnosperms haploid and derived from the
sterile portion of the female gametophyte.

entire: having a smooth margin, not dissected or toothed. Fig. 24.
entomophilous: pollinated by insects.

ephemeral: short-lived.

epicalyx: a whorl of bracts, just below a flower, looking like a second calyx.
epicarp: the outer layer of the wall of a fruit, i.e. the ‘skin’.

epicormic: of buds, shoots or flowers, borne on the old wood of trees (applied
especially to shoots arising from dormant buds after injury or fire).

epidermis: the outermost layer of cells of an organ, usually only one cell thick.

epigeal: of germination, having the cotyledon(s) emerging from the seed coat and
becoming photosynthetic. cf. hypogeal.

epigynous: of floral parts (especially stamens), attached above the level of insertion of
the ovary, and arising from tissue that is fused to the ovary wall. cf. hypogynous,
perigynous. Fig. 26.

epipetalous: borne on the petals. Fig. 26.

epiphyllous: growing on leaves, e.g. applied to vegetatively propagated plantlets in
some Crassulaceae.

176

Glossary

epiphyte: a plant growing on, but not parasitic on, another plant (often loosely
applied to plants, such as orchids, that grow on vertical rock faces).

eremean: pertaining to regions of low, irregular rainfall.

eusporangiate: of ferns, having sporangia with walls more than one cell thick.
cf. leptosporangiate.

evergreen: bearing green leaves throughout the year.

exine: the outer layer of the wall of a pollen grain or spore.

exserted: protruding, e.g. of stamens with respect to a corolla tube.

exstipulate: without stipules.

extra-floral: of nectaries, not within the flower.

extrorse: of anthers, opening away from the centre of the flower.

facultative: of parasites, optional. cf. obligate.

falcate: sickle-shaped. Fig. 23.

family: a group of one to many genera believed to be related phylogenetically, usually
clearly separable from other such groups.

farinaceous: containing starch grains; mealy; resembling flour.

fascicle: a cluster, adj. fasciculate.

fenestrate: having openings or translucent areas (‘windows’).

fertilisation: the union of male and female gametes.

filament: the stalk of a stamen; a thread one or more cells thick; in blue-green Algae,
a trichome enclosed in a mucilaginous sheath.

filiform: thread-like. Fig. 23.

fistular: hollow throughout its length.

flaccid: limp; tending to wilt. cf. turgid.

flexuous (= flexuose): bent from side to side in a zig-zag form

floral: belonging to or associated with a flower.

floret: a grass flower, together with the lemma and palea that enclose it (often applied
to flowers in Cyperaceeae and Asteraceae).

flower: the sexual reproductive structure of the angiosperms, typically consisting of
gynoecium, androecium and perianth and the axis bearing these parts. J

foliaceous: leaf-like.

follicle: a dry, dehiscent fruit formed from one carpel and dehiscing along the line of
fusion of its edges.

forb: a non-woody plant other than a grass, sedge, rush, etc. cf. herb. os

free: not fused or united (with other organs).

free-central: a placentation in which the ovules are borne on a free-standing central
placenta within the ovary. Fig. 25.

frond: a leaf especially of a fern, cycad or palm; a leaf-like portion of a non-vascular
plant (e.g. a foliose alga).

fruit: the seed- -bearing structure in angiosperms formed from the ovary after
flowering.

frutescent: becoming shrub-like (woody).

fruticose: shrub-like.

fugacious: falling or withering away very early.

funicle (= funiculus): the stalk of an ovule.

fusiform: spindle-shaped, i.e. narrower at both ends than at the centre.

177

Glossary

gamete: a cell or nucleus that fuses with another, of opposite sex, in sexual repro—
duction.

gametophyte: a plant, or phase of a plant’s life cycle, that bears gametes.

gamopetalous (= sympetalous): with the petals united by their margins, at least at
the base.

gamophyllous: having the leaves or perianth segments united by their margins, at
least at the base.

gamosepalous: having the sepals united by their margins, at least at the base.
geniculate: bent abruptly like a knee joint.

genotype: the total complement of hereditary factors (genes) acquired by an organism
from its parents and available for transmission to its offspring. cf. phenotype.

genus: a group of species believed to be related phylogenetically and usually clearly
separable from other such groups, or a single species without close relatives. pl.
genera.

geophyte: a plant whose perennating buds are buried in the soil.

glabrescent: becoming glabrous.

glabrous: without hairs.

gland: a structure, within or on the surface of a plant, with a secretory function.
glandular: bearing glands; functioning as a gland.

glaucous: blue-green in colour, with a whitish bloom (as in the juvenile leaves of
many eucalypts).

globose: nearly spherical.

glomerule: a small compact cluster. adj. glomerulate.

glumaceous: glume-like, tending to be chaffy or membranous in texture.
glume: a bract in the inflorescence of a grass, sedge or similar plant.

grain: a fruit characteristic of grasses (= caryopsis); pollen grain, a microspore of a
seed plant, or the partially developed gametophyte formed from it.

gymnosperm: a seed plant with the ovules borne on the surface of a sporophyll.
cf. angiosperm.

gynobasic: of a style, arising near the base of the gynoecium, e.g. between the lobes
of the ovary.

gynodioecious: having bisexual flowers and female flowers, on separate plants.
gynoecium: the carpels of a flower collectively.

gynophore: a stalk bearing the gynoecium above the level of insertion of the other
floral parts.

gynostemium: see column.
habit: the growth form of a plant, comprising its size, shape, texture and orientation.
habitat: the environment in which a plant lives.

half-inferior: of an ovary, partly below and partly above the level of attachment of
the perianth and stamens. Fig. 26.

halophyte: a plant adapted to living in highly saline habitats; a plant that accumulates
high concentrations of salt in its tissues.

haploid: having a single set of chromosomes in the nucleus (i.e. having each gene
locus represented only once).

hastate: spear-shaped; of a Jeaf blade, narrow and pointed but with two basal lobes
spreading approximately at right angles. Fig. 23.

178

Glossary

haustorium: an absorbing organ through which a parasite obtains chemical substances
from its host.

helicoid: coiled; of a cymose inflorescence, branching repeatedly on the same side.

herb: any vascular plant that never produces a woody stem. cf. forb.

herbaceous: not woody; soft in texture.

hermaphrodite: = bisexual.

heterogamous: producing flowers of two or more kinds with respect to their fertile
organs, e.g. male and female or bisexual and female. cf. homogamous.

heteromorphous (= heteromorphic): of two or more distinct forms.

heterosporous: producing separate male and female spores. cf. homosporous.

hilum: the scar on a seed coat at the place where it was attached to its stalk during
development. ;

hirsute: bearing coarse, rough, longish hairs. cf. villous.

hispid: bearing stiff, bristly hairs.

hoary: covered with a greyish layer of very short, closely interwoven hairs.

holotype: a single specimen designated by the author of a plant (or animal) name, at
the time of original publication, as that to which the name shall apply; the
‘voucher specimen’ of a name.

homogamous: having flowers of only one kind. cf. heterogamous.

homosporous: producing only one kind of spore in the sexual reproductive cycle, and
hence one gametophyte which produces both male and female gametes.
cf. heterosporous. ‘

host: an organism on which a parasite lives and by which it is nourished (also
applied, loosely, to a plant supporting an epiphyte).

hyaline: translucent, almost like clear glass.

hybrid: an offspring of genetically different parents (in a Flora, usually applied where
the parents are of different species).

hygroscopic: absorbing water and undergoing movements or changes brought about
by changes in water content.

hypanthium: a cup or tube bearing floral parts above the base, and often above the
top, of the ovary of a flower, e.g. in many Myrtales. .

hypocotyl: the part of the stem of an embryo or young. seedling below the
cotyledonary node.

hypogeal: of germination, having the cotyledon(s) remaining within the seed coat.
cf. epigeal. w

hypogynous: arising below the level of insertion of the ovary (often applied, loosely,
to a flower in which the sepals, petals and stamens are inserted below the ovary).
cf. perigynous, epigynous. Fig. 26.

imbricate: of perianth parts, having the edges overlapping in the bud. Fig. 25.

imparipinnate: having an uneven number of pinnae, by virtue of having one terminal
pinna. cf. paripinnate. Fig. 24.

incised: cut deeply, sharply and often irregularly (an intermediate condition between
toothed and lobed). Fig. 24.

included: enclosed, not protruding.

incumbent: of the orientation of an embryo, with the cotyledons lying face to face
and folded downwards beside the radicle; of anthers, lying against the inner face
of the filament.

179

Glossary

incurved: bent or curved inwards or upwards; of /eaf margins, curved towards the
adaxial surface.

indefinite: variable in number; numerous; of stamens, more than twice as many as the
petals or sepals; of an inflorescence, not terminating in a flower (i.e. having a
continuing, terminal growing point).

indehiscent: not opening at maturity.

indeterminate (= monopodial): of growth, the condition in which the terminal bud
persists and produces successive lateral branches.

indumentum: the epidermal appendages, e.g. hairs or scales, collectively.
induplicate: folded inwards so that the outer faces of the margins are in contact.
indusium: tissue covering the sorus of a fern; the pollen-cup of Goodeniaceae.

inferior: of an ovary, at least partly below the level of attachment of the other floral
parts. cf. superior. Fig. 26.

inflexed: bent sharply upwards or forwards.

inflorescence: the group or arrangement in which flowers are borne on a plant.
infraspecific: of lower taxonomic rank than species.

insectivorous: catching, and ostensibly feeding on, insects.

inserted (om): attached to; arising from.

integument: a covering; one of the outer layers of tissue of an ovule.

internode: the portion of a stem between the level of insertion of two successive
leaves or leaf pairs (or branches of an inflorescence).

interpetiolar: of stipules, between the petioles of two opposite leaves.
cf. intrapetiolar.

interrupted: of an inflorescence, having the flowers unevenly distributed along the
axis, with conspicuous gaps.

intramarginal: situated inside but close to the margin, e.g. of a vein in a leaf.

intrapetiolar: between a petiole and the subtending stem. cf. interpetiolar.

introduced: not indigenous; not native to the area in which it now occurs.
cf. adventive.

introrse: of anthers, dehiscing towards the centre of the flower.

involucre: a group of bracts enveloping a condensed inflorescence; a layer of tissue
enveloping particular structures, e.g. an archegonium in Bryophyta, sporangia in
Hymenophyllaceae.

involute: rolled inwards; of a Jeaf, with the margins rolled towards the adaxial
surface.

irregular: see zygomorphic.

isolateral (=isobilateral): having structurally similar upper and lower surfaces.

isotype: a specimen which is, or is believed to be, a duplicate of the holotype,
i.e. part of the same collection.

juvenile: of /eaves, formed on a young plant and different in form from the adult
leaves.

karyoevolution: evolutionary change in the chromosome set, expressed as changes in
number and gross structure of the chromosomes; (more broadly), evolutionary
relationships between taxa as indicated by karyotype differences.

karyotype: the gross morphology of the chromosome set, described in terms of
number, length, centromere position, etc.

180

Glossary

keel: a ridge like the keel of a boat; in particular, a boat-shaped structure formed by
fusion of the two anterior petals of a flower in Fabaceae.

keeled: of leaves or bracts, folded and ridged along the midrib.

labellum: a lip; in Orchidaceae, the distinctive median petal that serves as an
alighting platform for pollinating insects.

laciniate: slashed into narrow, pointed lobes. Fig. 24.

lacuna: a gap or cavity.

lamella: a thin, plate-like layer; middle lamella, the layer between the walls of two
adjacent cells.

lamina: the blade of a leaf.

lanceolate: of a /eaf, about four times as long as it is broad, broadest in the lower
half and tapering towards the tip. Fig. 23.

latex: a viscous fluid exuded from the cut surfaces of the leaves and stems of certain
plants.

leaflet: one of the ultimate segments of a compound leaf.

lectotype: a specimen selected from among those cited with the original description
to serve in place of a holotype where the holotype is missing or destroyed, or
where no holotype was designated.

legume: a fruit characteristic of the families Mimosaceae, Caesalpiniaceae and
Fabaceae, formed from one carpel and either dehiscent along both sides, or
indehiscent; in particular, such a fruit that is grown as an edible crop; a crop
species in the family Fabaceae.

lemma: the lower of two bracts enclosing a grass flower.

lenticel: a loosely-packed mass of cells in the bark of a woody plant, visible on the
surface of a stem as a raised powdery spot, through which gaseous exchange
occurs.

lenticular: shaped like a biconvex lens.

lepidote: covered with small, membranous scales.

leptosporangiate: of ferns, having sporangia with walls only one cell thick. cf. eu-
sporangiate.

liane: a climbing or twining plant (usually applied to woody climbers).

lignotuber: a woody swelling below or just above the ground, containing adventitious
buds from which new shoots develop if the top of the plant is cut or burnt
(common in the shrubby eucalypts and in many other fire-tolerant Australian
shrubs).

ligulate: bearing a ligule; strap-shaped.

ligule: a strap-shaped structure; a membranous or hairy appendage on the adaxial
surface of a leaf, especially in grasses, at the junction between sheath and blade; a
small adaxial appendage near the leaf base in some pteridophytes; the corolla limb
in ray flowers of Asteraceae.

limb: the upper, free, spreading portion of a corolla or perianth that is connate at the
base.

linear: very narrow in relation to the length, and with the sides parallel. Fig. 23.

lithophyte: a plant that grows on the surface of unweathered rock.

loculicidal: of the dehiscence of a fruit, along lines coinciding with the centres of
loculi. cf. septicidal.

loculus: an enclosed compartment within an organ e.g. an ovary, an anther. pl. loculi.

“A

181

Glossary

lodicule: one of a pair of tiny scales in a grass floret, between the lemma and the
fertile parts of the flower, which may be reduced perianth segments.

lomentum: a legume having distinct constrictions or lines of abscission between the
seeds and breaking into one-seeded segments when mature.

lyrate: deeply lobed, with a large terminal lobe and smaller lateral ones. Fig. 24.

macrospore: = megaspore.

mallee: a growth habit in which several woody stems arise separately from a ligno—
tuber (usually applied to shrubby eucalypts); a plant having the above growth
habit.

marginal: occurring at or very close to the margin.

megagametophyte: a plant body or cell lineage, formed by vegetative growth of the
megaspore, that produces the female gametes of a heterosporous plant.

megasporangium: the larger of the two kinds of sporangia produced in the sexual life
cycle of a heterosporous plant.

megaspore: the larger of the two kinds of spores produced in the sexual life cycle of a
heterosporous plant, giving rise to the female gametophyte.

megasporophyll: a specialised leaf upon (or in the axil of) which one or more mega—
sporangia are borne.

meiosis: the two-stage division of a diploid nucleus, occurring once in every sexual
life cycle, in which gene recombination occurs and the number of chromosomes
characteristic of the sporophyte plant is halved prior to the production of gametes.

mericarp: one segment of a fruit that breaks at maturity into units derived from the
individual carpels. cf. schizocarp.

meristem: growing regions of a plant in which cells that have retained their
embryonic characteristics, or reverted to them secondarily, divide to produce new
cells.

mery: the number of parts per whorl that characterises a particular flower (generally
constant for the perianth whorls and less often for the whorl(s) of stamens also).
adj. merous.

mesocarp: the fleshy portion of the wall of a succulent fruit inside the skin and
outside the stony layer, if any, surrounding the seed(s).

mesophyll: photosynthetic tissue of a green plant; of vegetation, characteristic of
moist habitats and with soft, fairly large leaves predominating; a leaf whose area is
within the approximate range 20-180 square cm.

microgametophyte: a plant body or cell lineage, formed by vegetative growth of the
microspore, that produces the male gametes of a heterosporous plant.

micropyle: a small canal through the integument(s) of an ovule, persisting as a pore
in the seed coat.

microsporangium: the smaller of the two kinds of sporangia produced in the sexual
life cycle of a heterosporous plant.

microspore: the smaller of the two kinds of spores produced in the sexual life cycle of
a heterosporous plant, giving rise to the male gametophyte.

microsporophyll: a specialised leaf upon (or in the axil of) which one or more micro—
sporangia are borne.

midrib: the central, and usually the most prominent, vein of a leaf or leaf-like organ.
monadelphous: of stamens, united by their filaments into one bundle.

monocarpic: flowering and fruiting only once during its life span.

monochasium: a cymose inflorescence with the branches arising singly. cf. dichasium.

182

Glossary

monochlamydeous: of a flower, having only one whorl of perianth parts.

monocotyledon: a flowering plant whose embryo has only one cotyledon (seed leaf).
cf. dicotyledon.

monoecious: having the male and female reproductive structures in separate flowers
but on the same plant. cf. dioecious.

monophyletic: derived from a single ancestral line. cf. polyphyletic.

monopodial: of growth, with a persistent terminal growing point producing many
lateral organs successively; of a stem, growing in the above manner.
cf. sympodial.

monotypic: containing only one taxon of the next lower rank (e.g. applied to a family
containing only one genus). cf. polytypic.

morphology: the form and structure of an organism or part of an organism; the study
of form and structure.

motile: actively moving; self-propelled.

mucilage: slimy material exuded by certain plants or plant organs. adj. mucilaginous.

mucro: a sharp, abrupt terminal point. adj. mucronate. Fig. 23.

muricate: rough on the surface due to minute, hard outgrowths of the epidermis.

mycorrhiza: a symbiotic union between a fungus and a plant root.

naked: of sporangia, not covered by an indusium; of seeds, exposed on the surface of
a sporophyll (not enclosed within an ovary); of flowers, without perianth; of
protoplasts or gametes, not bounded by a cell wall.

nectary: a gland that secretes nectar. adj. nectariferous.

neotype: a specimen selected to serve in place of a holotype where none of the
material to which the name was originally applied is known to have been
preserved.

nerve: a vein.

neuter: sterile (e.g. of flowers in which neither the androecium nor the gynoecium is
functional in reproduction).

nocturnal: of flowers, opening only at night.

node: the level (transverse plane) of a stem at which one or more leaves arise.

nomen conseryandum: a name of a family or genus (or taxon intermediate between
these two) that has been formally accepted as the correct name contrary to the
usual principles of botanical nomenclature.

nomen illegitimum: a name which, at the time of its publication, was superfluous
(because the taxon to which it was applied had already been named) or had
already been applied to another plant.

nomen nudum: a name published without a diagnosis or description of the entity to
which it applies, and without reference to either.

nomen rejiciendum: a name rejected in favour of a ‘nomen conservandum’.

nucellus: the central tissue of an ovule, within which the megaspore mother cell is
formed.

nut: a hard, dry, indehiscent fruit formed from two or more carpels but containing
only one seed.

obconical: cone-shaped but attached at the narrower end.

obcordate: of a leaf blade, broad and notched at the tip; heart-shaped but attached at
the pointed end. Fig. 23.

oblanceolate: similar in shape to lanceolate but attached at the narrower end.

183

Glossary

obligate: of parasites, unable to survive without the host. cf. facultative.

oblique: of a /eaf or leaflet, larger on one side of the midrib than on the other,
i.e. asymmetrical. Fig. 23.

obloid: (a three-dimensional shape) with short, parallel sides and rounded ends, as if
composed of two hemispheres linked together by a very short cylinder.

oblong: having the length greater than the width but not many times greater, and the
sides parallel. Fig. 23.

obovate: similar in shape to ovate but attached at the narrower end. Fig. 23.
obsolescent: non-functional but not reduced to a rudiment.
obsolete: reduced to a rudiment, or completely lacking.

obtuse: blunt or rounded at the apex, the converging edges separated by an angle
greater than 90 degrees. Fig. 23.

ochrea: a sheath, formed from two stipules, encircling the node in Polygonaceae.

ontogeny: the development of a single organism, i.e. the sequence of stages through
which it passes during its lifetime.

operculum: a lid or cover becoming detached at maturity by abscission; in Eucalyptus
(for example), a cap covering the bud and formed by fusion or cohesion of
perianth parts.

opposite: of /eaves, borne at the same level but on opposite sides of the stem; of
floral parts, on the same radius (as). cf. alternate.

orbicular: circular or nearly so. Fig.23.

order: a taxonomic grouping of families believed to be closely related (sometimes a
single family with no apparent close relatives).

orthotropous: of an ovule, erect so that the micropyle points away from the placenta.
Fig. 25.

ovary: the basal portion of a carpel or group of fused carpels, enclosing the ovule(s).

ovate: shaped like a section through the long axis of an egg, and attached by the
wider end. Fig. 23.

ovoid: egg-shaped (in three dimensions). cf. ovate.
ovulate: with ovules.

ovule: a structure in a seed plant within which one or more megaspores are formed
and which develops into a seed after fertilisation.

ovuliferous: bearing ovules (e.g. applied to scales in a megasporangiate cone in gym-—
nosperms).

palea: in a grass floret, the upper one of the two bracts enclosing a flower.
palmate: of a /eaf, divided into several leaflets which arise at the same point. Fig. 24.

palmatifid: of a leaf, deeply divided into several lobes which arise (almost) at the
same level. Fig. 24.

palmatisect: a condition intermediate between palmate and palmatifid, with the green
tissue of the lamina completely divided into several segments, but the segments
not fully separated at the base. Fig. 24.

palynology: the scientific study of pollen.

panicle: a compound raceme; an indeterminate inflorescence in which the flowers are
borne on branches of the main axis or on further branches of these.

paniculate: indeterminate and much branched.

papilla: a small, elongated protuberance on the surface of an organ, usually an exten—
sion of one epidermal cell. adj. papillose.

184

Glossary

pappus: a tuft (or ring) of hairs or scales borne above the ovary and outside the
corolla in Asteraceae and possibly representing the calyx; a tuft of hairs on a fruit.

parasite: an organism living on or in a different organism and deriving nourishment
from it. cf. saprophyte, epiphyte.

paratype: a specimen, other than the holotype, that was cited with the original pub-
lication of a name.

parenchyma: plant tissue consisting of mature, living cells that are relatively un—
specialised in function.

parietal: attached to the margins of a structure; of placentation, having the ovules
attached to placentas on the wall of the ovary. Fig. 25.

paripinnate: having an even number of pinnae by virtue of having a pair in the
terminal position. cf. imparipinnate. Fig. 24.

-partite: divided, almost to the base, into segments (commonly applied to a style).

pedicel: the stalk of a flower. adj. pedicellate.

peduncle: the stalk of an inflorescence; in ferns, the stalk of a sporocarp. adj. ped—
unculate.

pellucid: transparent.

peltate: of a leaf, having the stalk attached to the lower surface of the blade, not to
the margin (also applied, in the same sense, to other stalked structures). Fig. 23.

pendulous: drooping; of ovules, attached at the top of the ovary and hanging
downwards from an apical placenta.

penicillate: pencil-shaped; tufted like an artist’s brush.

penniveined: with conspicuous lateral veins diverging from the midrib and lying
approximately parallel to each other.

pentamerous: of a flower, having five parts in each floral whorl (not necessarily in—
cluding the gynoecium).

perennate: maintain a dormant, vegetative state throughout non-growing seasons.

perennial: a plant whose life span extends over more than two growing seasons.

perfoliate: of a sessile leaf or bract, having its base completely wrapped around the
stem.

perianth: the calyx and corolla of a flower, especially where the two are similar.

pericarp: the wall of a fruit, developed from the ovary wall.

perigynous: of perianth segments and stamens, arising from a cup or tube (hypan—
thium) that is free from the ovary but extending IO its base. cf. hypogynous,
epigynous. Fig. 26.

perisperm: nutritive tissue in an angiospermous seed, formed from the “‘nucellus. cf.
endosperm.

persistent: remaining attached to the plant beyond the expected time of falling
(e.g. of sepals not falling after flowering).

petal: a member of the inner whorl of non-fertile parts surrounding the fertile organs
of a flower, usually soft and coloured conspicuously.

petaloid: like a petal; soft in texture and coloured conspicuously.

petiole: the stalk portion of a leaf.

petiolule: the stalk portion of a leaflet.

phanerogam: (literally) a plant with conspicuous reproductive parts; a plant repro—
ducing by seeds. cf. cryptogam.

185

Glossary

phenotype: the physical characteristics of an organism; the outward expression of
characteristics conferred on an organism by its genotype.

phloem: the tissue in the conducting system of a plant through which metabolites
(products of chemical reactions in the plant) are transported.

phylloclade: a very leaf-like, photosynthetic stem of a plant whose true leaves are
much reduced. cf. cladophyll.

phyllode: a leaf whose blade is much reduced or absent, and whose petiole and rachis
have assumed the functions of the whole leaf. cf. cladode.

phyllotaxy: the arrangement of leaves on a stem (when spiral, often expressed quan—
titatively as the fraction of the circumference of the stem that separates two suc—
cessive leaves).

phylogeny: the evolutionary development of a plant group, i.e. its derivation from its
ancestors and the relationship among its members. adj. phylogenetic.

phylum: a taxon of high rank, the major unit of classification. cf. division.
pilose: hairy, the hairs soft and clearly separated but not sparse.

pinna: a primary segment of the blade of a compound leaf.

pinnate: divided into pinnae; once-compound. cf. bipinnate. Fig. 24.

pinnatifid: cut deeply into lobes that are spaced out along the axis (of the leaf).
cf. palmatifid. Fig. 24.

pinnatisect: dissected down to the midrib but having the segments confluent with it.
Fig. 24.

pinnule: a leaflet of a bipinnate leaf.

pistil: a free carpel or a group of fused carpels.

pistillode: a sterile pistil, often rudimentary.

pith: the central region of a stem, inside the vascular cylinder.
placenta: a region, within an ovary, to which ovules are attached.

placentation: the arrangement of placentas, and hence of ovules, within an ovary.
Fig. 25.

plicate: folded back and forth longitudinally like a fan.
plumose: like a feather; with fine hairs branching from a central axis.

plumule: the portion of an embryo that gives rise to the shoot system (as distinct
from the root system) of a plant. cf. radicle.

pod: a leguminous fruit.

pollen: the microspores of seed plants; the powdery mass of microspores shed from
anthers.

pollen-sac: see sac.

pollination: the transfer of pollen from the male organ, where it is formed, to the
receptive region of a female organ, e.g. from anther to stigma.

pollinium: a cohering mass of pollen grains, transferred as a unit in pollination. pl.
pollinia.

polygamodioecious: having bisexual and male flowers on some plants, and bisexual
and female flowers on others.

polygamous: having bisexual and unisexual flowers on the same plant.
polymorphic: having more than two distinct morphological variants.
polypetalous: with free petals. cf. gamopetalous.

polyphyletic: composed of members that originated, independently, from more than
one evolutionary line. cf. monophyletic.

186

Glossary

polyploid: having more than two of the basic sets of chromosomes in the nucleus.

polytypic: containing more than one taxon of the next lower rank. cf. monotypic.

pome: a fleshy (false) fruit, formed from an inferior ovary, in which the receptacle or
hypanthium has enlarged to enclose the true fruit.

posterior: of floral parts, on the side of the flower nearest to the axis. cf. anterior.

prickle: a hard, pointed outgrowth from the surface of a plant, involving several
layers of cells but not containing a vein.

procumbent: trailing or spreading along the ground but not rooting at the nodes.

propagule: a structure with the capacity to give rise to a new plant, e.g. a seed, a
spore, part of the vegetative body capable of independent growth if detached from
the parent.

prophyll: a leaf formed at the base of a shoot, usually smaller than those formed
subsequently.

prostrate: lying flat on the ground.

protandrous: having the male sex organs maturing before the female; of a flower,
shedding the pollen before the stigma is receptive. cf. protogynous.

prothallus: a gametophyte body, especially in ferns and related plants.

protogynous: having the female sex organs maturing before the male; of a flower,
shedding the pollen after the stigma has ceased to be receptive. cf. protandrous.

proximal: near to the point of origin or attachment. cf. distal.

pseudo-: false; apparent but not genuine.

puberulous: covered with minute, soft, erect hairs.

pubescent: covered with short, soft, erect hairs.

pulyinus: a swelling at the base of the stalk of a leaf or seas, often glandular or res—
ponsive to touch.

punctate: marked with dots.

pungent: ending in a stiff, sharp point; having an acrid taste or smell.

pyrene: the ‘stone’ (endocarp plus seed) of a succulent fruit. cf. drupe.

quincuncial: of the arrangement of corolla lobes in a bud, a variant of imbricate aes—
tivation. Fig. 25.

raceme: an indeterminate inflorescence in which a main axis produces a series of
flowers on lateral stalks, the oldest at the base and the youngest at the top. adj.

racemose.

rachilla: the axis of a grass spikelet, above the glumes.

rachis: the axis of an inflorescence or a pinnate leaf; pl. rachises. secondary rachis:
the axis of a pinna in a bipinnate leaf.

radical: of /eaves, clustered at the base of the stem.

radicle: the portion of an embryo that gives rise to the root system of a plant.
cf. plumule.

raphe: the part of the stalk of an anatropous ovule that is fused along the side of the
ovule.

raphides: needle-like crystals that occur in bundles in the vacuoles of some plant
cells.

ray: a zygomorphic flower in Asteraceae; a radial band of cells traversing the con—
ducting elements in woody stems.

receptacle: the axis of a flower (= torus); in ferns, an axis on which sporangia arise.

recurved: curved or curled downwards or backwards.

187

Glossary

reflexed: bent sharply downwards or backwards.

regular: see actinomorphic.

reniform: kidney-shaped. Fig. 23.

replum: a longitudinal partition in an ovary, formed between parietal placentas.
resupinate: twisted through 180 degrees, e.g. as with the ovary of most Orchidaceae.
reticulate: forming a network.

retinaculum: a hook-like structure to which another structure is tethered; in Orchid-
aceae and Asclepiadaceae, the structure to which pollen masses are attached; in
Acanthaceae, the persistent stalk of an ovule.

retrorse: directed backwards or downwards. cf. antrorse.
retuse: with a very blunt and slightly notched apex. Fig. 23.
revolute: rolled downwards or backwards.

rhachilla: = rachilla.

rhachis: = rachis.

rhizoid: a thread-like, unicellular absorbing structure, occurring in fern gametophytes
and in some non-vascular plants.

rhizome: an underground stem, usually growing horizontally.
rhizophore: in Selaginella, a leafless stem that produces roots.
rhomboid: quadangular, with the lateral angles obtuse. Fig. 23.

root: a unit of the axial system of a plant which is usually underground, does not bear
leaves, tends to grow downwards and is typically derived from the radicle of the
embryo. See adventitious.

rootstock: a short, erect, swollen structure at the junction of the root and shoot
systems of a plant.

rostellum: a beak-like upward extension of the stigma in Orchidaceae.

rotate: circular and flattened, e.g. of a corolla with a very short tube and spreading
lobes.

rudimentary: poorly developed and not functional. cf. vestigial, obsolete.
rugose: deeply wrinkled.

ruminate: mottled in appearance, e.g. of bark, or of the food reserves in a seed.
runcinate: deeply lobed and with the lobes slanted away from the apex. Fig. 24.

runner: a slender, prostrate or trailing stem which produces roots and sometimes
erect shoots at its nodes.

sac: a pouch or cavity; pollen-sac: a cavity, in an anther, in which pollen is formed;
embryo-sac: a large, multi-nucleate cell in which an egg nucleus is formed and
fertilised, and in which an embryo begins to develop.

saccate: pouched.
sagittate: shaped like an arrow-head. Fig. 23.
samara: a dry, indehiscent fruit with its wall expanded into a wing.

saprophyte: an organism deriving its nourishment from dead organic matter and
usually lacking chlorophyll. cf. parasite.

scabrid (= scabrous): rough to the touch.

scale: a reduced or rudimentary leaf, e.g. surrounding a dormant bud; a thin flap of
tissue, e.g. on the ventral surface of a liverwort thallus and at the base of a
stamen in Simaroubaceae.

scandent: climbing.

188

Glossary

scape: the stem-like, flowering stalk of a plant with radical leaves.

scarious: dry and membranous.

schizocarp: a dry fruit formed from more than one carpel but breaking apart into
1-carpel units when ripe.

sclerenchyma: mechanical tissue with heavily thickened cell walls.

scleromorph: a plant whose leaves (or stems, if leafless) are hard in texture, usually
having thick cuticle and containing many fibres. cf. xeromorph.

sclerophyllous: with leaves stiffened by sclerenchyma.

scorpioid: of a cymose inflorescence, branching alternately on one side and then the
other. cf. helicoid.

secund: with all the parts grouped on one side or turned to one side (applied
especially to inflorescences).

seed: a propagating organ formed in the sexual reproductive cycle of gymnosperms
and angiosperms, consisting of a protective coat enclosing an embryo and food
reserves.

segment: a part or sub-division of a divided organ; one of a group of similar organs
named collectively, e.g. one petal = a segment of a corolla.

sepal: a member of the (usually green) outer whorl of non-fertile parts surrounding
the fertile organs of a flower.

sepaloid: looking like sepals, e.g. of bracts, usually green and arranged in a ring
beneath a flower.

septate: divided internally by partitions.

septicidal: of the dehiscence of a fruit, along lines Bainerine with the partitions
between loculi. cf. loculicidal.

septum: a partition. pl. septa.

seriate: in rows or whorls.

sericeous: silky; covered with silky hairs.

serrate: toothed, with asymmetrical teeth pointing forward. Fig. 24.

serrulate: finely serrate. Fig. 24.

sessile: without a stalk (when applied to a stigma, indicates that the style is absent,
the stigma being ‘sessile’ on the ovary). ,

seta: a bristle or stiff hair; in Bryophyta, the stalk portion of a sporophyte plant body.
terminal seta: an appendage to the tip of an organ, e.g. the primary rachis of a
bipinnate leaf in Acacia.

setose: bristly. w~

shrub: a woody plant less than 5 metres high, either without a distinct main axis, or
with branches persisting on the main axis almost to its base.

siliceous: containing silica.

silicula: a short siliqua, not more than twice as long as its width.

siliqua: a dry, dehiscent fruit formed from a superior ovary of two carpels, with two
parietal placentas and divided into two loculi by a false septum between the
placentas.

simple: undivided; of a Jeaf, not divided into leaflets; of a hair or an inflorescence,
not branched.

sinuate: with deep, wave-like depressions along the margin. cf. undulate. Fig. 24.

sinus: a notch or depression in the margin of an organ.

solitary: of flowers, borne singly, not grouped in an inflorescence.

189

Glossary

sorus: in ferns, a discrete group of sporangia. pl. sori.

spadix: a spicate inflorescence with a stout, often succulent axis.
spathaceous: like a spathe; with a spathe.

spathe: a large bract ensheathing an inflorescence.

spathulate (= spatulate): spoon-shaped; broad at the tip and narrowed towards the
base. Fig. 23.

species: a taxon comprising individuals, or populations of individuals, capable of
interbreeding to produce fertile offspring; the largest group of individuals between
which there are no distinguishable, consistent differences in form or reproductive
mechanisms.

spike: an unbranched, indeterminate inflorescence in which the flowers are without
stalks. adj. spicate.

spikelet: a unit of the inflorescence in grasses, sedges and some other mono-
cotyledons, consisting of one to many flowers and associated glumes.

spine: a stiff, sharp-pointed structure, formed by modification of a plant organ, e.g. a
lateral branch or a stipule.

spinescent: ending in a spine; modified to form a spine.

spinose: bearing spines.

spiral: of Jeaves or floral organs, borne at different levels on the axis, in an ascending
spiral. cf. cyclic.

sporangiophore: the stalk of a sporangium.

sporangium: a structure within which spores are formed. pl. sporangia.

spore: a simple propagule, produced either sexually or asexually, and consisting of
one or a few cells.

sporocarp: a fruiting body containing sporangia.
sporogenous: of cells or tissues, in which spores are formed.
sporophyll: a specialised leaf-like organ on which one or more sporangia are borne.

sporophyte: a plant, or phase of a life cycle, that bears the spores formed during the
sexual reproductive cycle.

spur: a tubular pouch at the base of a perianth part, often containing nectar.

stamen: one of the male organs of a flower, consisting typically of a stalk (filament)
and a pollen-bearing portion (anther). adj. staminate.

staminode: a sterile stamen, often rudimentary.
standard: the posterior petal in the flower in Fabaceae.
stellate: star-shaped; consisting of star-shaped cells.

stem: the main axis or a branch of the main axial system of a plant, developed from
the plumule of the embryo and typically bearing leaves.

stigma: the pollen-receptive surface of a carpel or group of fused carpels, usually
sticky.

stipe: a small stalk; in ferns, the petiole of a frond; in algae, the cylindrical basal
portion of a thallus.

stipitate: stalked; borne on a stipe; of an ovary, borne on a gynophore.

stipule: one of a pair of appendages at the bases of leaves in many dicotyledons.

stolon: a prostrate or trailing stem that produces roots at the nodes.

stoloniferous: having stolons; trailing over the soil surface and rooting at the nodes.

stoma: a pore; a pore in the epidermis of a leaf or other aerial organ, providing access
for gaseous exchange between the tissues and the atmosphere. pl. stomata.

190

Glossary

stomium: a region of dehiscence, e.g. of an anther in flowering plants or of a capsule
in mosses. pl. stomia.

striate: striped with parallel longitudinal lines or ridges.

strigose: with sharp, stiff hairs which are slanting rather than erect.

strobilus: a ‘cone’ consisting of sporophylls borne close together on an axis.

strophiole: = caruncle.

style: an elongated part of a carpel, or group of fused carpels, between the ovary and
the stigma.

subulate: narrow and tapering gradually to a fine point. Fig. 23.

sulcate: grooved; furrowed.

superior: of an ovary, borne above the level of attachment of the other floral parts,
or above the base of a cup (hypanthium) that is free from the ovary and bears the
perianth segments and stamens. cf. inferior. Fig. 26.

suture: a line of junction between two fused organs; a line of dehiscence.

syconium: a multiple fruit with a hollow centre, e.g. in Ficus (fig).

sympatric: of two or more species, having coincident or ovarlapping ranges of dis—
tribution. cf. allopatric.

sympetalous: = gamopetalous.

sympodial: of growth, without a single, persistent growing point; changing direction
by frequent replacement of the growing apex by a lateral growing point below it;
of a stem, growing in the above manner. cf. monopodial.

synandrium: an androecium with the anthers of the stamens cohering. cf. syngen—
esious.

syncarpous: of a flower, having two or more carpels, all fused together.

syngenesious: of the stamens of one flower, fused together by the anthers e.g. in
Asteraceae.

syntype: one of two or more specimens cited by the author at the time of publication
of a name for which no holotype was designated.

taproot: the main, descending root of a plant that has a single, dominant root axis.

taxon: a group or category, at any level, in a system for classifying plants or animals.

tendril: a slender climbing organ formed by modification of a part of a plant, e.g. a
stem, a leaf or leaflet, a stipule.

tepal: a perianth segment in a flower in which all the perianth segments are similar in
appearance.

terete: cylindrical or nearly so; circular in cross-section.

terminal: at the apex or distal end.

ternate: in groups of three; of /eaves, arranged in whorls of three; of a single leaf,
having the leaflets arranged in groups of three. Fig. 24.

terrestrial: of or on the ground; of the habitat of a plant, on land as opposed to in
water, or on the ground as opposed to on another plant.

testa: a seed coat.

tetrad: a group of four; four pollen grains remaining fused together at maturity, e.g. in
Ericaceae, Epacridaceae.

tetradynamous: of an androecium, consisting of four stamens of the same length and
two of a different length.

tetramerous: of a flower, having four segments in each perianth whorl, and usually in
each whorl of stamens also.

eal

191

Glossary

thallus: the vegetative body of a plant that is not differentiated into organs such as
stems and leaves, e.g. algae, the gametophytes of many liverworts, and Lem-
naceae.

thorn: a modified plant organ, especially a stem, that is stiffened and terminates in a
pungent point.

throat: of a corolla tube, the top, where the tube joins the lobes.

thyrse: a branched inflorescence in which the main axis is indeterminate and the lat—
eral branches determinate in their growth.

tomentum: a covering of dense, matted, woolly hairs. adj. tomentose.
torus: see receptacle.
trabecula: a transverse partition dividing or partly dividing a cavity.

tree: a woody plant at least 5 metres high, with a main axis the lower part of which
is usually unbranched.

trichome: an unbranched epidermal outgrowth, e.g. a hair, a papilla; in blue-green
algae, a single row of cells in a filamentous colony.

trichotomous: branching almost equally into three parts.

trifid: deeply divided into three parts.

trifoliate: having three leaves.

trifoliolate: of 2 /eaf, having three leaflets.

trigonous: triangular in cross-section and obtusely-angled. cf. triquetrous.

trimerous: of a flower, having three segments in each perianth whorl and usually in
each whorl of stamens also.

tripinnate: of /Jeaves, thrice pinnately divided.

triquetrous: triangular in cross-section and acutely-angled; with three distinct
longitudinal ridges. cf. trigonous.

truncate: with an abruptly transverse end, as if cut off. Fig. 23.

tuber: a storage organ formed by swelling of an underground stem or the distal end
of a root.

tubercle: a small wart-like outgrowth.

tuberculate: covered with tubercles.

tuberous: swollen; of roots, tuber-like.

turgid: swollen due to high water content. cf. flaccid.
type: a designated representative of a plant name.

umbel: a racemose inflorescence in which all the individual flower stalks arise in a
cluster at the top of the peduncle and are of about equal length.

undulate: wavy, i.e. not flat. cf. sinuate. Fig. 24.

unifoliate: having one leaf.

unifoliolate: of a leaf, basically compound, but reduced to only one leaflet.
unilocular: of an ovary, anther or fruit, having only one internal cavity.

unisexual: bearing only male or only female reproductive organs.

united: fused together.

urceolate: urn-shaped.

utricle: a small bladder; a membranous bladder-like sac enclosing an ovary or fruit.

valvate: of sepals or petals in a bud, meeting edge to edge, not overlapping. cf. im—
bricate. Fig. 25.

192

Glossary

valve: a portion of an organ that has fragmented; of a capsule, the teeth-like portions
into which the dehiscing part of the pericarp splits at maturity.

vascular: specialised for conduction of fluids; vascular plants: plants containing
specialised conducting tissues.

vein: a strand of vascular tissue.

velamen: a water-retaining outer layer of the aerial roots of some epiphytes, especially
orchids.

velum: a membranous covering; a veil.

venation: the arrangement of veins in a leaf.

ventral: of a Jateral organ, facing towards the subtending axis; of a thallus, facing
towards the substratum. cf. dorsal.

yernation: the arrangement of unexpanded leaves in a bud. cf. aestivation.

versatile: of anthers, swinging freely about the point of attachment to the filament,
which is approximately central.

verticillate: arranged in one or more whorls.

vesicle: a bladder-like sac or cavity filled with gas or liquid.

vessel: a capillary tube formed from a series of open-ended cells in the water-
conducting tissue of a plant.

vestigial: reduced from the ancestral condition and no longer functional. cf. rudi-
mentary.

villous: shaggy with long, weak hairs.

viscid: of a surface, sticky; coated with a thick, syrupy secretion.

viscous: of a liquid, not pouring freely; having the consistency of syrup or honey.

viviparous: of seeds or fruits, germinating before being shed from the parent plant.

whorl: a ring of leaves, bracts or floral parts borne at the same level on an axis.

wing: a membranous expansion of a fruit or seed, which aids dispersal; a thin flange
of tissue extended beyond the normal outline of a stem or petiole; a lateral petal
of a flower in Fabaceae.

xeromorph: a plant having structural features usually associated with plants of arid
habitats (such as hard or succulent leaves) but not necessarily drought-tolerant.
cf. xerophyte. ;

xerophyte: a drought-tolerant plant.

xylem: the tissue, in a vascular plant, that conducts water and mineral salts from the
roots to the leaves. ,

zygomorphic: of a flower or calyx or corolla, symmetrical about one ptane only, usu—
ally the plane that bisects the flower vertically. cf. actinomorphic.

193

Oey

> ———

188)
oO

<=)
oH)

Adv iv bvevdv Qiang

DD) -EE (FE IGG

Figures 23. A-P-Leaf shapes: A-subulate; B-acicular; C-filiform; D-linear; E-oblong;
F-falcate; G-lanceolate; H-elliptic; I-ovate; J-obovate; K-orbicular and peltate;
L-deltoid; M-rhomboid; N-cuneate; O-reniform; P-spathulate. Q-V-—Leaf bases:
Q-cordate; R-hastate; S-sagittate; T—auriculate; U-oblique; V-truncate. W-GG-Leaf
tips: W-aristate; X—-caudate; Y—acuminate; Z-acute; AA-cuspidate; BB-mucronate;
CC-apiculate; DD-obtuse; EE-retuse; FF-emarginate; GG-—obcordate.

Oo P Q R Ss T U v \w

Figure 24. Division of leaves: A-lyrate; B—pinnatifid; C-pinnatisect; D-incised;
E-laciniate; F-runcinate; G—palmatifid; H-palmatisect (= digitate); I-palmate;
J-trifoliolate; K-ternate (strictly, biternate); L-M-pinnate (L-paripinnate,
M-imparipinnate); N-bipinnate; O-entire; P-serrate; Q-serrulate; R-dentate;
S—denticulate; T-crenate; U-crenulate; V-sinuate; W-undulate.

Aa@ ac
aA® 6@®

Figure 25. A-—D-Aestivation: A-C-imbricate (A-cochlear, B-—quincuncial,
C-convolute); D-valvate. E-J—placentation: E-axile; F-free-central; G-—parietal;
H-marginal; I-basal; J-apical. K-M-—Orientation of ovules: K-—orthotropous;
L-anatropous; M-campylotropous.

\e9

Figure 26. Positions of floral organs: A-perianth and stamens hypogynous, ovary
superior; B—perianth and stamens perigynous, ovary superior; C-perianth and stamens
hypogynous, stamens epipetalous, ovary superior; D-perianth and stamens epigynous,
ovary half-inferior; E-perianth and stamens epigynous, ovary inferior.

INDEX

Acacia, 59

Airy Shaw, H. K., 83

Andrews, E. C., 27

Angiospermae, 78

Anthophyta, 78

ANZAAS, 5, 6, 7, 8, 10

Australasian Herbarium News, 5

Australian Academy of Science, 6
Flora and Fauna Committee, 7, 9

Standing Committee for a Flora of Australia,
8

Australian Biological Resources Study (ABRS),
9, 10

Advisory Committee, 10
functions, 9
Interim Council, 9
Australian flora
alien species, 11
Antarctic element, 26, 27
arid zone, 59, 61, 62, 63
Australian element, 26, 27, 50
autochthonous element, 26, 44, 45
conservation, 66
dysploidy, 45
endemism, 44
eremean, 60
Gondwanan, 42, 44, 51, 55
Indomalayan element, 26, 27
invasion theory, 26, 29
karyoevolution, 28
pollination and breeding systems, 65
polyploidy, 45, 64
scleromorphy, 45
size, 6
state of knowledge, 9, 11
Tertiary immigration, 51
uniqueness, 25, 66
Australian and New Zealand Association for
the Advancement of Science (ANZAAS),
5, 6, 7, 8, 10
Flora of Australia Committee, 6
Australian Plant Name Index, 8, 9

Australian Science and Technology Council
(ASTECQ), 9, 10

Australian Systematic Botany Society, 8

Bass Strait, 55

Beard, J. S., 6, 7

Bentham, G., ii, 4

Bentham, G. & Hooker, J. D., 81
Biological Survey of Australia, 7
Black, J. M., 3

Blake, S. T., 6

Bowler, J. M., 61

Brown, R., 12, 78

Burbidge, N. T., 8, 9, 27, 28
Bureau of Flora and Fauna, 11

Catcheside, D. G., 8

Class, 78

Committee of Heads of Australian Herbaria, 10
Continental displacement, 30, 31, 40, 41
Continental drift, 30

Convergent evolution, 82

Cormophyta, 78

Crocker, R- L., 27, 61

Cronquist, A. J., 11, 82, 91

CSIRO, 8

Dahlgren, R. M. T., 100
Darwin, C., 79
Dicotyledoneae, 78
Diels, L., 27, 60
Division, 78

Editorial Committee for the Flora of Australia,
10

Eichler, Hj., 5, 7

Embryobionta, 78, 79

Engler, A., 89

Eucalyptus, 58

Family, 78
Flora Australiensis, 3, 4, 5, 6, 14, 81

Flora of Australia, 3, 10, 79, 82
see also Australian flora

Editorial Committee, 10, 82
Flora of Central Australia, 8

Generic Flora of Australia, 8
Genus, 77
Gondwanan flora, 42, 44, 51, 55

199

Index

Hartley, W., 5
Herbert, D. A., 29

Hierarchy of botanical taxonomic classification,
77, 79, 80

Hooker, J. D., 17, 25, 26
Hopper, S. D., 44
Hutchinson, J., 87

Indomalayan land bridge, 27

Institute of Australian Flora and Fauna (IAFF),
10

Invasion theory, 26, 29

Jessop, J. P., 3, 8
Jussieu, A. L. de, 78, 79

Karyoevolution, 28
Kingdom, 78

Lamarck, J. Monnet de, 79
Land bridges, 27, 30
Liliopsida, 78

Lindley, J., 15

Linnaeus, C., 77
Loranthaceae, 51

McKenna, M. C., 40, 41
Maiden, J. H., 3
Magnoliophyta, 78, 79, 82, 101
Magnoliopsida, 78

Mawby, Sir M., 7, 8, 9
Melchior, H., 89
Monocotyledoneae, 78
Mueller, F. von, 3, 14, 18

Natural system of classification, 78, 81
Nelson, E. C., 52
New Guinea, 50, 54

Order, 78
Origin of angiosperms, 41

Palaeoclimate, 33

Palaeogeography, 31

Phylogenetic system of classification, 81
Phylogenetic ‘tree’, 81, 100, 101, 103
Plate tectonics, 30, 31

Regional Floras, 7, 8

200

Schwarz, O., 27

Sexual system of classification, 77
Smith-White, S., 28

Society for Growing Australian Plants, 8
South West Botanical Province, 44
Species, 77

Specific epithet, 77

Stearn, W. T., 7

Steenis, C. G. G. J. van, 9

Takhtajan, A., 93
Tasmania, 55
Tate, R., 27, 60
Taxon (taxa), 77
Thorne, R. F., 95
Torres Strait, 54

Western Australia, 44
Wilson, P. G., 10
Wood, J. G., 5, 27, 61

se a ert em vas:

Sia Wier
od. spy Aba

Diy : —
me Yu ae Weta

Flora of Australia — Index to families of flowering plants

Volume
Acanthaceae 33
Aceraceae 25
Actinidiaceae 6
Agavaceae 46
Aizoaceae 4
Akaniaceae 25
Alangiaceae 22
Alismataceae 39
Amaranthaceae 5
Anacardiaceae 25
Annonaceae 2
Apiaceae 27
Apocynaceae 28
Aponogetonaceae 39
Aquifoliaceae 22
Araceae 39
Araliaceae 27
Arecaceae 39
Aristolochiaceae 2
Asclepiadaceae 28
Asteraceae 37,38
Austrobaileyaceae 2
Balanopaceae 3
Balanophoraceae 22
Basellaceae 5
Bataceae 8
Berberidaceae
Betulaceae 3
Bignoniaceae 33
Bixaceae 8
Bombacaceae 7
Boraginaceae 30
Brassicaceae 8
Bromeliaceae 45
Brunoniaceae 35
Burmanniaceae 47
Burseraceae 25
Byblidaceae 10
Cabombaceae 2
Cactaceae 4
Caesalpiniaceae 12
Callitrichaceae 32

Campanulaceae
Cannabaceae
Cannaceae
Capparaceae
Caprifoliaceae
Cardiopteridaceae
Caryophyllaceae
Casuarinaceae
Celastraceae
Centrolepidaceae
Cephalotaceae
Ceratophyllaceae
Chenopodiaceae
Chrysobalanaceae
Cistaceae
Clusiaceae
Combretaceae
Commelinaceae
Connaraceae
Convolvulaceae
Corsiaceae
Corynocarpaceae
Costaceae
Crassulaceae
Cucurbitaceae
Cunoniaceae
Cuscutaceae
Cymodoceaceae
Cyperaceae
Datiscaceae
Davidsoniaceae
Dichapetalaceae
Dilleniaceae
Dioscoreaceae
Dipsacaceae
Donatiaceae
Droseraceae
Ebenaceae
Elaeagnaceae
Elaeocarpaceae
Elatinaceae
Epacridaceae

SURVE7

SE L-IDaAF

I 6D {

Volume

34
3
45
8
36

wonraa

Ericaceae
Eriocaulaceae
Erythroxylaceae
Eucryphiaceae
Euphorbiaceae
Eupomatiaceae
Fabaceae
Fagaceae
Flacourtiaceac
Flagellariaceae
Frankeniaceae
Fumariaceae
Gentianaceae
Geraniaceae
Gesneriaceae
Goodeniaceae
Grossulariaceae
Gunneraceae
Gyrostemonaceae
Haemodoraceae
Haloragaceae
Hamamelidaceae
Hanguanaceae
Hernandiaceae
Himantandraceae
Hippocrateaceae
Hydatellaceae
Hydrocharitaceae
Hydrophyllaceae
Icacinaceae
Idiospermaceae
Iridaceae
Juncaceae
Juncaginaceae
Lamiaceae
Lauraceae
Lecythidaceae
Leeaceae
Lemnaceae
Lentibulariaceae
Liliaceae
Limnocharitaceae

Volume

2
13,14,15
3

Linaceae
Loganiaceae
Loranthaceae
Lythraceae
Magnoliaceae
Malpighiaceae
Malvaceae
Marantaceae
Melastomataceae
Meliaceae
Melianthaceae
Menispermaceae
Menyanthaceae
Mimosaceae
Molluginaceae
Monimiaceae
Moraceae
Moringaceae
Musaceae
Myoporaceae
Myristicaceae
Myrsinaceae
Myrtaceae
Najadaceae
Nelumbonaceae
Nepenthaceae
Nyctaginaceae
Nymphaeaceae
Ochnaceae
Olacaceae
Oleaceae
Onagraceae
Opiliaceae
Orchidaceae
Orobanchaceae
Oxalidaceae
Pandanaceae
Papaveraceae
Passifloraceae
Pedaliaceae
Philydraceae
Phytolaccaceae

Volume

19,20,21
39

An Oh

22
32
18
22
47
33
27
39

33
45

Piperaceae
Pittosporaceae
Plantaginaceae
Plumbaginaceae
Poaceae
Podostemaceae
Polemoniaceae
Polygalaceae
Polygonaceae
Pontederiaceae
Portulacaceae
Posidoniaceae
Potamogetonaceae
Primulaceae
Proteaceae
Punicaceae
Rafflesiaceae
Ranunculaceae
Resedaceae
Restionaceae
Rhamnaceae
Rhizophoraceae
Rosaceae
Rubiaceae
Ruppiaceae
Rutaceae
Salicaceae
Santalaceae
Sapindaceae
Sapotaceae
Saxifragaceae
Scrophulariaceae
Simaroubaceae
Smilacaceae
Solanaceae
Sonneratiaceae
Sparganiaceae
Sphenocleaceae
Stackhousiaceae
Stemonaceae
Sterculiaceae
Stylidiaceae

Volume

10
32

43,44
18
30
24

39
39
10
16,17

Surianaceae
Symplocaceae
Taccaceae
Tamaricaceae
Theaceae
Thymelaeaceae
Tiliaceae
Trapaceae
Tremandraceae
Triuridaceae
Tropaecolaceae
Typhaceae
Ulmaceae
Urticaceae
Valerianaceae
Verbenaceae
Violaceae
Viscaceae
Vitaceae
Winteraceae
Xanthophyllaceae
Xanthorrhocaceae
Xyridaceae
Zannichelliaceae
Zingiberaceae
Zosteraceae
Zygophyllaceae

dud

Volume

10
10
46
8
6
18
7
18
24
39
27
45
3
3
36
30
8
22
24
2
24
46
40
39
45
39
26

jiuseul

of Victoria

FLORA OF AUSTRALIA

The series Flora of Australia, planned to comprise approximately 50 volumes to be
published over a 20-year period, is designed for use by persons with some botanical
knowledge who require information on the names, characteristics, distribution and
habitat of Australian plants.

George Bentham’s Flora Australiensis, the only previous Australia-wide F lora, was
written in England and published between 1863 and 1878. It contained 8125 species. _
The new Flora, written by many botanists, will describe all the native and naturalised
plants of Australia, currently estimated to be over 20 000 species. Co-ordinated and
edited by the Bureau of Flora and Fauna, Department of Home Affairs and
Environment, it will contain keys for identification, colour and black and white
illustrations and distribution maps.

This introductory volume contains chapters on the history and purpose of the Flora
of Australia project, the origin and evolution of the Australian flora, and the systematic
arrangement of plant families. It includes a key for the identification of families of
flowering plants and a glossary of botanical terms.

Cover: Helichrysum ayersii F. Muell. and Prilotus obovatus (Gaudich.) F. Muell., near the —
_ Cayenagh Range, central Western Australia (Photograph A. S. George). —

_ R80/770(1) Cat. No.8109572,

Internet Archive Audio

Featured

Top

Images

Featured

Top

Software

Featured

Top

Books

Featured

Top

Video

Featured

Top

Mobile Apps

Browser Extensions

Archive-It Subscription

Save Page Now

Full text of "Flora of Australia. Vol. 1 : Introduction"

See other formats