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Classified daisies.

A group of small unassuming daisies (Euchiton) is being investigated as there is confusion surrounding the differences between species. This project is investigating whether some plants in New Zealand and Australia are the same species or not and what the evolutionary relationships are in Euchiton. A background to the field of Systematic Botany is given, including a brief discussion of cladistics, an analytical method used to analyse the evolution of groups. The implications of this work and field for the broader community are outlined.
ODE TO TAXONOMY

 The language used is truly jargon
 Latin, but jargon none-the-less
 Inbred terminology of the most exclusionary kind
 And yet I love it.

 I am in the borderline edge world
 Where the flickerings of understanding
 Are not yet strong enough to drown out
 the lyrical, rhythmical beauty.

 I smile when the scabrosity of the
 involucral bracts is a defining character,
 I revel in the twin myxogenic hairs
 found on the cypselas under high magnification.

 And not only are the finely denticulate
 pappas bristles a delight for the description,
 They are a visual feast.

 I got distracted using the scanning electron microscope
 ($120 an hour).
 I stopped taking scientific images at
 comparable magnitudes of the cypsela surface
 And started storing images--straight to disk, mind you
 Of these fine toothed appendages
 that fly the seeds to good fortune
 Their elongated tips
 Crossing in the image formed from
 electrons reflecting from the gold coating
 Real gold on real fruit of real plants.

 To only compare the morphology
 And not stop to revel in its beauty
 Is a travesty.

 There should be an allocation in
 every taxonomic budget
 for appreciating the beauty of the subject.
 For stopping in the field,
 specimens hanging dead in your hand
 Destined to be flattened for posterity
 And drinking in the fields of yellow buttons.

 Or taking a minute, or sixty,
 to listen to the sounds those golden
 scabrous involucral bracts make
 As they mutter in the wind,
 Jostling each other in a crackling wave.

 Taking the time to arrange
 the corpses of your beloved study object
 In an artistic manner
 As it is to stay forever.

 To register audibly the flash of beauty
 As a bract tip comes into focus
 Glorious in bright orange,
 Every fibre defined,
 ending in their shaggy chaos
 --the roughness in reality.

 To worship the arachnid e-glandular
 hairs that tangle to a snow-white
 density the abaxial surface
 of the lanceolate, cauline, petiolate leaves

 In the reductionism it is still
 possible to see the wonder
 That the beautiful exclusive terms
 define so precisely.


INTRODUCTION

I am excited by daisies and taxonomy, the subjects of my PhD studies, as shown in the above poem. This opportunity to describe the work I'm doing and try to place it in a broader context is also exciting, although attempting to outline the point of a postgraduate research project resulting in a thesis is not a simple task, just as no thesis is a simple undertaking. There are multifaceted purposes for the existence of each and every thesis. Some of these purposes are intrinsic to the task, such as the role of the thesis as a platform on which to acquire new skills and further career prospects, but it is not these that we are discussing here. What we wish to investigate is the intellectual significance and role of a particular project within the greater scheme of things. This question obliges a thorough justification of the pursuance of academic work beyond the concept that knowledge for knowledge's sake is an acceptable reason. We are being asked to assess the role of the work in question beyond the confines of the field within which the study is based.

By the nature of the academy and the specificity of postgraduate research, most research remains within the sanctuary of the specialised field. Barriers of terminology and basically accepted premises stand between each isolated research group, let alone communication with the broader community. This is, I feel, a failing of the academic system. We are taught to use the terms within our field and slowly build a wall of jargon between us and everyday language. Even Latin, a highly respectable language, can be a form of jargon as it is the dominant force of the language barrier in my field, as referred to in my poem. This use of specialised language is necessary: these terms are highly precise and describe things more concisely than lay terminology would; however, there is no reciprocal process later in our education when we are taught to re-translate the specific into general terms.

EUCHITON AND ITS SPECIES CONFUSION

The main question being addressed by this project is whether a number of species in a closely related species complex are actually distinct species or all part of one large variable continuous species. Currently there is confusion about the differences between two alpine species in particular, Euchiton argentifolius and Euchiton traversii. These species have similar physical characteristics, both having attractive silvery leaves in small clustered rosettes. The flowers themselves are tiny and not showy, but cluster into heads surrounded by bracts which look like little stars after the fruit has blown away. Euchiton traversii was described in New Zealand (1) while E. argentifolius was described in Australia. (2) The name E. traversii has been applied to plants found in Australia alongside plants bearing the name E. argentifolius. (3) The differences between these two entities and several others are very small, and identifying them has proven difficult--which is why this project was designed. You may have thought that all the species of plants are well known and sorted out, but it is still a vibrant evolving field.

SYSTEMATIC BOTANY

The overarching field of Systematic Botany is the methodical classification of the plant life on earth. The basis for this field was laid down by Carolus Linneaus, an eighteenth century botanist and physician. (4) The Linnean classification system 'places every species into a category based upon its evolutionary position in relation to other species. The largest taxonomic (classificatory) group is the phylum followed by the class, order, family, genus and species'. (5) The general 'idea of classification is to provide a means of reference to the individuals and also to crystallise the relationships between the various types'. (6) This is achieved using a series of word constructions to denote the different levels.

Within this field, Botanical Taxonomy studies the classification and delimitation of plant taxa (plural of 'taxon', 'a group of organisms of any taxonomic rank e.g. family, genus, or species') (7). Taxonomists describe new species and produce up-to-date information regarding the currently accepted names of species. Most taxonomists work at herbaria such as the National Herbarium of Victoria, producing texts such as Flora of Victoria (8) and journals such as Muelleria.

Paul Wilson, a taxonomist working out of the Perth Herbarium, has recently produced a manuscript for the Flora of Australia (a series of publications detailing the plants of Australia) addressing the genus Euchiton. He initially decided that the two names of the alpine taxa mentioned earlier referred to the same taxon and called them all E. traversii, (9) suggesting that there is no difference between the two species based on the material he studied. In a subsequent version of the manuscript he has changed his mind and retained the name E. argentifolius, (10) illustrating the unresolved nature of this group. The assessments of earlier workers have been undertaken using only morphological (physical) characters, whereas this project contributes quantitative computer-aided analyses incorporating molecular as well as morphological evidence.

We are attempting to come up with a system of classification that best fits the plant world, using the available tools and techniques. We are creating levels of word boxes with which to describe the variation in nature. There is a rich history of botanical nomenclature, and essentially most of the work is now adding detail and clearing up the minutiae of the overarching system that is in place. Although I earlier maligned the use of Latin terminology as exclusive, it is actually the universal language of taxonomists, allowing a standardised forum across the world within which to describe biological organisms. 'The property of no one nation or linguistic group, Latin has, in consequence of its neutrality, become world-wide.' (11) In some ways it could be argued that this is because it is just as alien and unknown to everyone, but it is more due to the co-evolution of Botanical Latin and the Linnean System.

Systematic botany is a dynamic field, where new species can be described at any time. Somebody looking through material collected over the years, pressed and stored in a herbarium, may notice a pattern of difference that was not apparent when the individual specimens were collected. Often groups have much variation within them, and on close scrutiny more taxa are present than was initially believed. This has occurred several times with E. traversii in New Zealand. Three species have been split from E. traversii over the years, (12) and the validity of these taxa requires investigation since they are notoriously hard to identify. In Australia two species have been described that were previously included in E. argentifolius. (13)

VITAL UNDERPINNINGS

Systematic and taxonomic information is the vital underpinning of all ecological and land management work. Many, many taxa make up the biological knowledge base and the solid basis and acceptance of each taxon is imperative. We need to know plant distinctions so we can identify the species present in an area that is, for example, potentially to be developed. Ecology bases many conclusions on species diversity, which can only be accurately assessed and enumerated when the taxonomy of the species involved is stable and thoroughly understood. Management practices are often based on monitoring the species diversity and composition of an area of vegetation. This can only be done well when the species present are reliable and, as such, systematic biology in general is very important.

The results of this study will promote an understanding of conservation by adding information about both the Australian and New Zealand native flora and elucidating how many species of Euchiton are present in New Zealand and which are shared with Australia. This is important for understanding the distribution of species and identifying those in need of conservation attention.

Another branch of systematics is Phylogenetic Systematics, which analyses the evolutionary relationships between taxa using tools such as cladistic analysis. This field produces cladograms, branching tree diagrams, illustrating hypotheses about which taxa are more closely related to each other. So far no phylogenetic analysis offering evidence regarding the evolutionary relationships of the species to each other within this genus has been undertaken. This project will produce a phylogeny of Euchiton based on both morphological and molecular characters. The approach to analysing the species confusion and relationships within the genus utilises phenetics as well as cladistics.

PHENETICS AND CLADISTICS

Most taxonomy is based on comparing what the plants in a group look like and clustering the ones that look similar together. The physical comparisons made tend to be based on characters of leaves, flowers and fruit. Leaf length, shape and hairiness, colour and number of petals, number of male parts (stamens), number and type of fruit, and size and ornamentation of seeds, are just a few of those that may be used. Comparison using molecular techniques are now also common. Some of these physical comparisons are done by sorting through many specimens of a group and using the human brain to analyse the similarities and then measure the range of the variation. Other studies utilise computers and enter data matrices of many characters to extract patterns that identify groups. These techniques survey a large number of characters that have the potential to offer useful patterns and come loosely under the heading of 'phenetics'.

The analysis technique I referred to earlier, cladistics, employs a different philosophy. Characters for a cladistic (phylogenetic) analysis are carefully picked and must be homologous. This means they must be comparing things that are the same structures in an evolutionary sense. In lay terms, for the basic premise of cladistics to work you need to be comparing apples with apples. For instance, comparing a 'flower' of a sunflower, as it is commonly understood, with a magnolia flower would not be comparing apples with apples, because the sunflower has a compound head made up of many tiny flowers, the outside ones having a floral tube that looks like one big petal and the centre ones being a simple tube. In daisies the anthers (pollen-producing male parts) are also fused into a tube. Conversely, the magnolia flower comprises a single flower with free petals and free anthers.

Once you are happy that the structures you are comparing are homologous, cladistics employs comparison with an 'outgroup'. This is a group of plants, or a single plant depending on the level of study, which is thought to have diverged from the group of study earlier in evolutionary time. The basic premise is that this outgroup will have characters that are more 'ancient', and comparing these with the study group will show where differences have arisen and where 'derived' character states (those which show an evolutionary change) have occurred. Let us assume that a simpler structure indicates an older form. To use the same example again, the magnolias are thought to have diverged earlier than the daisies. Daisies have a complicated compound head with several different types of flowers with fused petals in different combinations, while magnolias have a simple one flowered head with unfused petals. Assessing these changes using an Occam's Razor approach, parsimony, a tree of the relationships (cladogram) can be created which is based on the shortest possible number of steps. As nature is not perfectly linear, some characters do alter several times or 'return' to the 'ancient' state. These are known as 'conflicting characters'. So the relationship of the taxa is shown with the least conflict. The cladogram produced is your hypothesis about how these taxa are related to each other.

In general, studies analysing taxa at or below the species level use phenetic tools, while above this level cladistic analysis gives useful information.

DAISY BACKGROUND

When working with nature, and plants in particular, we need to accept that there is a certain amount of chaos inherent in natural systems. While we can come to a good understanding of the classification, we are always putting arbitrary boxes on a continuum. I am in the process of trying to refine the boxes into which the species of Euchiton have been placed. The point of my project is to clarify the human interpretation of the natural variation that comprises the genus Euchiton. Within Euchiton there are currently twenty-two species recognised. The genus is placed in the family Asteraceae (the daisies, also once known as the Compositae). Within the family Asteraceae there are subdivisions above the generic level called 'tribes', and Euchiton is considered to be part of the tribe Gnaphalieae.

The Asteraceae is the most species-diverse family of terrestrial plants in the world. It comprises approximately 20,000 species and around 1,300 genera. (14) The daisies are considered to be one of the more recently evolved groups of terrrestrial plants, partly based on the high number of 'derived' characters in the group. Asteraceae have been divided into many different groups throughout the history of plant taxonomy. The number of tribes has fluctuated greatly, as has the numbers of subtribes and genera. The large number of taxa involved means that many groups have not been thoroughly studied. Also, new technology improves analyses available to the study of systematics, and many groups have not previously had the benefit of computer aided similarity analysis or molecular techniques applied to offer evidence for their relationships and taxon delimitations.

It is here that my project fits in. Although Euchiton was initially described in 1828 (15) by Cassini, it was included within a larger genus, Gnaphalium, from 1838 until 1974. The tribe Gnaphalieae takes its name from this genus. In 1838 De Candolle (16) retained the name Euchiton as a section within Gnaphalium, but it wasn't recognised as a genus again until 1974, (17) although the larger botanical community didn't seem to notice and in 1991 another author re-separated the group. (18) Within the genus Euchiton, species numbers have varied from eleven (19) to sixteen (20) to the current twenty-two. (21) There are many questions that remain to be answered regarding this genus. These questions relate mostly to the differences between species and whether some currently accepted species, particularly those found in Australia and New Zealand, are the same with different names (synonyms). Also needing investigation are issues relating to the biogeography of Euchiton.

SPECIES DEFINITION

The main aim of this project is to clarify the confusion associated with species definitions in this genus. I have already mentioned the concept of species and how it is the taxonomic level below genus. The definition of species needs a little more discussion, for it is not quite as simple as suggested so far. There has long been the 'biological species concept' based on the concept of reproductive isolation, that is, two taxa not being able to produce fertile offspring. This can often be applied successfully to animals but not always to plants, as many have the ability to hybridise. It has actually been shown that Euchiton can even produce viable hybrids with species from other genera. (22) This does not mean, however, that the species within the two genera are the same thing and should be known by the same name. There are other ways of being reproductively isolated than the actual process of reproduction failing due to biological incompatibility.
 A number of factors ... tend to keep different species of plants
 distinct when they occur together ... For example, two plant
 species capable of forming fertile hybrids may occur in the same
 area but in different habitats ... Among the other mechanisms
 that can prevent the formation of hybrids between species that
 occur together are seasonal differences in time of flowering.
 If two species do not flower together they will not hybridize
 in nature even when they grow side by side. Alternatively,
 they may be pollinated by different kinds of insects or other
 animals. (23)


So species can be taken to mean 'a group of organisms that resemble one another closely'. (24) In different groups, different characters are important in defining the taxa, as different aspects vary. There is no universal way of defining how much difference is different enough, nor can there practically be. Genetic variation can possibly give some sort of answer as to how distinct different taxa are, but unless the technology becomes much more advanced, cheaper and easy to carry out, identifying plants when undertaking fieldwork in the reality of nature will still rely on physical characteristics.

In essence, the decision about what constitutes a species in each case comes down to the taxonomist working on the group. It is basically a case of human interpretation of the facts put before us based on tradition. This is the same in so many fields, such as law, in which we put much faith. The more evidence we have to back up a decision, the more convincing the conclusion. A good taxonomic treatment should offer a key that successfully identifies the species during fieldwork. My project aims to use several lines of evidence to assess the species delimitations within the genus and produce a key that helps clearly identify the different taxa in the field.

THE PROJECT

There is invaluable information stored in the collections held at herbaria all over the world. I currently have 3,000 specimens on loan from all around Australia and several overseas locations. I will subject this material and field-collected specimens to both a phenetic and cladistic analysis in order to address the species level questions and also produce a phylogeny of the genus.

The data for these analyses will come from a set of approximately one hundred characters being recorded for each specimen to create a comprehensive morphological database. A molecular technique, Amplified Fragment Length Polymorphisms (AFLPs), will also be used to compare the variation within populations of each taxon to the variation between taxa. This process involves cutting DNA into fragments and creating multiple copies of selected fragments. Fragments are labelled so they can be separated on size and the resulting banding patterns can be read and compared. If the species are distinct, the variation within should be less than that between them and the taxa should have different banding patterns. If, however, there is a continuum across the taxa sampled with no marked disjunctions, then the taxa currently recognised potentially belong to the one species.

Those are the immediate goals of the project, but there will be a wider significance beyond the small circle of taxonomists who will be pleased that a new hypothesis for Euchiton has been put forward.

IMPORTANCE OF RELIABLE SPECIES

Although it is common and apparently unremarkable, many ecologists and management workers have been very pleased to hear that I am working on Euchiton. This is because it is common and many people have come across it in their work and had difficulties identifying the species. This is not only frustrating when doing fieldwork but it contributes confusion to knowing how many species you have in an area and therefore decisions are made based on unreliable data. It is always preferable to draw conclusions and make decisions based on complete data. Essentially, it is necessary to be aware of the delimitation of taxa and their overall distribution as this sort of work provides the baseline data on which the biological, ecological and land management disciplines rely. The quality of these data is therefore important and contributes to wider conservation issues.

Having said earlier that we are just filling in the details of the overarching system, there is a plethora of details. The overarching system changes sometimes according to the current hypothesis about evolutionary relationships. Although this sort of project is very specific in nature, it can contribute data to larger analyses of higher level questions such as ongoing phylogenetic analyses of Asteraceae by other workers worldwide.

The more solid the lower taxonomic levels, the more stable the analyses of higher level ones. Inevitably, higher level (e.g. family) analyses are based on the lower ones. Again, if there is inaccuracy in the basic unit, the assessment at a higher level will come to a misleading answer. Currently the confusion within the Asteraceae at tribal level can be compounded by the confusion at genus level. Tribes can confuse subfamilies etc. So there are many questions and seemingly endless holes, and every new piece of more solidly confirmed evidence is precious and important.

Often work is concentrated on species of high profile families such as orchids, rare and threatened taxa, big conspicuous groups such as Eucalypts, or species with some sort of commercial value. This project looks at common, 'nondescript' small daisies. However, because this genus is common across Australia and New Zealand it occurs in many areas studied for other purposes. For example, species lists are generally kept for National Parks for identifying changes in species composition over time. It is important to study all plants, not just the pretty ones.

As with all pure academic research, whether in science, medicine or philosophy, there is always the potential to come across opportunist tangential findings. In this study I have documented evidence to support fears concerning weed invasion in the last 30 years in New Zealand alpine regions. This is an ecological issue of changes in the ecosystem, but it is also important in a management sense. Another daisy with a similar growth habit called Hieracium pilosella has recently expanded its range in New Zealand. The presence of this species has influenced a contraction of range for Euchiton traversii which was previously very common in many alpine settings. This goes to show again that it is important to look closely at so-called common species, since we sometimes find that the assumption of their widespread distribution is incorrect because circumstances have changed.

INTERNATIONAL SCOPE

The international scope of the project is particularly important, investigating the genus across its natural range rather than only within politically defined boundaries. Most botanical taxonomy is studied within political borders. The books which detail the plants in an area are known as 'floras', and their titles show the boundaries within which they are recorded. There are state-based treatments such as the Flora of Victoria (25) and Flora of South Australia, (26) as well as national ones such as the Flora of Australia (27)--which has come out as a series of volumes and is not yet complete. However, some plants have a cosmopolitan distribution over much of the globe and the variation in these is covered piecemeal. The species in Euchiton which have been causing taxonomic difficulties have been reassessed in both Australia (28) and New Zealand (29) but a complete answer has not yet been found. This project looks across all borders to answer the Australian--New Zealand questions and will stretch to South-east Asia for a cladistic analysis.

BIOGEOGRAPHY

Another applicable field to this project is Biogeography. This is the study of, among other things, 'the geographical distribution of plants and animals at different taxonomic levels, past and present'. (30) This information is gathered with a view to explaining the current distribution patterns and inferring their historical and evolutionary past. An important part of the project related to the international nature of the work is that of the biogeographic implications of the results. The biogeographic relationship of Australia and New Zealand is not yet fully clear. Using the cladistic trees resulting from this work, biogeographic inferences can be made with regard to the past associations of Australia and New Zealand land masses (if any). There is controversy regarding the biogeography of New Zealand in particular and the origin of its flora. There are a number of hypotheses regarding the relationships of the two floras.

Cladistic biogeography is dependent on multiple threads of evidence showing the same pattern before solid conclusions can be drawn. The results of this project will hopefully offer useful support for one hypothesis. This sort of study can also contribute information for larger scale questions such as Gondwanan issues. Most people have heard of Gondwana, the supercontinent proposed to have existed before the subsequent breakup and creation of the current mainly southern hemisphere continents through plate tectonics. Work on every small piece of the puzzle furnishes evidence to support or counter the larger theories such as plate tectonics and the Gondwanan supercontinent.

BROADER COMMUNITY

Several institutions, private companies and community groups in the broader community have an interest in the results of this sort of research. Herbaria are not part of the academy as such, although, being in the trade of pure research, this sort of study is an obvious extension of the work that is undertaken within the herbarium system. Results from studies such as this feed directly into the daily functioning of herbaria. Manaaki Whenua, Landcare Research in New Zealand, is sufficiently interested in this question to contribute a supervisor to the study. The Department of Conservation in New Zealand, Department of Natural Resources and Environment in Victoria and New South Wales National Parks Wildlife Service are some of the government institutions to have requested copies of publications from this work. They need to stay abreast of changes in taxonomy so that their conservation, management and species inventory is up to date. Private environmental and biological consultancies which use identification tools on a daily basis will eagerly accept a new key simplifying the identification process. And there are other groups, such as the Australian Daisy Study Group, which have an intense interest in this sort of work.

OTHER MOTIVATIONS

Returning to the point of the study, I designed this project because I wanted to extend my taxonomic skills, learn and apply cladistic analysis and investigate the biogeographic questions surrounding Australia and New Zealand's geological history. I chose daisies because, being the largest plant family, there is endless scope for more work in the group and I think they are amazing plants. Working with the fruit under Scanning Electron Microscope conditions has inspired me to write poetry and I think it is very important to be inspired by your work. I have described them as small unassuming cudweeds and to most people they don't rate on the interest stakes. Once you get to know your study object intimately you see things that others miss, such as the slight tint of purple in the tips of the four milimetre long cream florets or the bristles that are used in wind dispersal of the fruit (just like dandelion fruit). It is really beautiful and fulfilling to know something in so much detail and to love the characters that you use to analyse them with.

Another point of the project is getting to go to as many beautiful places as possible to collect specimens for the study. So far I have spent time collecting in the Victorian alpine region, hiked in Kosciuszko National Park in New South Wales and am soon to be visiting Tasmania as well. For two and a half months I travelled around New Zealand, covering 6,000 km over both islands searching for these daisies.

CONCLUSION

Resolving the species confusion in Euchiton is the underlying point of the project described in this essay. However, there are many associated issues which make the project important. Among these are the role that systematic botany plays in providing a solid underpinning for many other fields, including conservation. Reliable lower level taxonomy creates a stable platform upon which to base higher level analyses. The international nature of the project is also a very important aspect, and something that is often overlooked due to practicalities--meaning that implications for biogeography can be investigated with the results of the Euchiton study. Many institutions in the broader community will benefit from a clearer picture of the species comprising this genus. Of course, the beauty of the study objects and the areas in which they grow should not be overlooked, nor the ability of the subject matter to inspire poetry.

There are many points to this project that reach beyond the field of systematic botany and the answers are of interest to many people and institutions. The project is evaluating a complex question and can be shown to be valuable on several scales. It is important to support dialogue across the academic community and I hope that this essay has made the world of taxonomy and systematics more accessible to a wider audience.

ENDNOTES

(1) Joseph D. Hooker, Handbook of the New Zealand Flora, Reeve and Co., London, 1867, 154.

(2) Norman A. Wakefield, 'Flora of Victoria: New species and other additions-12', The Victorian Naturalist, vol. 73, 1957, 186-8.

(3) Neville G. Walsh, 'Euchiton', in Neville G Walsh and Tim J Entwisle (eds), Flora of Victoria Volume 4, Inkata Press, Melbourne, 1999, 820-5; Joy Everett, 'Gnaphalium', in Gwen J. Harden (ed.), Flora of New South Wales Volume 3, New South Wales University Press, Sydney, 1992, 206-10 and Winifred M. Curtis (ed.), The Student's Flora of Tasmania Part 2, Government Printer, Tasmania, 1963, 316-21.

(4) Michael Allaby (ed.), Oxford Concise Dictionary of Zoology, Oxford University Press, Oxford, 1996, 260.

(5) Gareth Jones, Alan Robertson, Jean Forbes and Graham Hollier, Collins Reference Dictionary of Environmental Science, Collins, London, 1990, 259.

(6) John H. Elliot, Botany, The English Universities Press Ltd, London, 1973, 189.

(7) Allaby, 461.

(8) Neville G. Walsh and Tim J. Entwisle, Flora of Victoria Volume 2 Ferns and Allied Plants, Conifers and Monocotyledons, Inkata Press, Melbourne, Victoria, 1994.

(9) Paul G. Wilson, Euchiton, Manuscript for Flora of Australia, unpubl., version 1.

(10) Paul G. Wilson, Euchiton, Manuscript for Flora of Australia, unpubl., version 2.

(11) William T. Stearn, Botanical Latin Fourth Edition, David and Charles, Devon, 1995, 9.

(12) Colin J. Webb, Gnaphalium, in Colin J. Webb, William R. Sykes, and Phil J. Garnock-Jones (eds), Flora of New Zealand Volume IV, Botany Division, DSR, Christchurch, 1988, 234-49; Donald Petrie, 'Descriptions of new native plants', Transactions and Proceedings of the New Zealand Institiute, vol. 22, 1890, 439-43 and David G. Drury, 'The cluster and solitary-headed cudweeds native to New Zealand (Gnaphalium section Euchiton-Compositae)', New Zealand Journal of Botany, vol. 10, 1972, 112-79.

(13) Max Gray, 'Miscellaneous notes on Australian plants: 3. Craspedia, Gnaphalium, Epacris, Tasmannia, Colobanthus and Deyeuxia', Contributions Herbaria Australiensis, nos. 18-26, 1976, 1-11, 2-5 and Neville G. Walsh, 'New Species in Asteraceae from the Subalps of Southeastern Australia', Muelleria, vol. 12, no. 2, 1999, 223-8.

(14) Kare Bremer, 'Tribal interrelationships of the Asteraceae', Cladistics, vol. 3, no. 5, 1987, 210-253, 210.

(15) Henri Cassini, 'Uchite', Dictionnaire des Sciences Naturelles, vol. 56, 1828, 214-218.

(16) Augustin Pyramis De Candolle, Prodromus Systematis Naturalis Regni Vegetabilis, vol. 6, Treuttel and Wurtz, Paris, 1838, 235-6.

(17) Joseph Holub, 'New Names in Phanerogamae 3', Folia geobotanica et phytotaxonomica, vol. 9, 1974, 261-75, 265-6.

(18) Arne A. Anderberg, 'Taxonomy and phylogeny of the tribe Gnaphalieae (Asteraceae)', Opera Botanica, 104, 1-195, 166-7.

(19) Augustin Pyramis De Candolle, Prodromus Systematis Naturalis Regni Vegetabilis, vol. 6, Treuttel and Wurtz, Paris, 1838, 235-6. 20 Anderberg, 166-7.

(21) Walsh, Euchiton, 820-5; Holub, 265-6 and Alex M. Buchanan, 'A new species of Euchiton (Gnaphalieae: Asteraceae) from Southern Tasmania, Australia', Papers and Proceedings of the Royal Society of Tasmania, vol. 133, no. 1, 1999, 115-6; Anderberg, 166-7; Josephine Ward and Ilse Breitwieser, 'Systematics of New Zealand Inuleae (Compositae)--4 A taxonomic review', New Zealand Journal of Botany, vol. 36, 1998, 165-71.

(22) Robert Mackenzie, Intergeneric hybridisation among the New Zealand Gnaphalieae (Compositae), PhD thesis, University of Canterbury, New Zealand, 2002.

(23) Peter H. Raven, Ray F. Evert and Susan E. Eichhorn, Biology of Plants, 5th ed., Worth Publishers, New York, 1992, 160.

(24) Allaby, 437.

(25) Walsh and Entwisle.

(26) John P. Jessop, and Hellmut R. Toelken, 'Gnaphalium', in John P. Jessop and Hellmut R. Toelken (eds), Flora of South Australia Part III Polemoniaceae-Compositae, South Australian Government Printing Division, Adelaide, 1986, 1516-9.

(27) Bureau of Flora and Fauna, Flora of Australia, Australian Government Publishing Service, Canberra, various years.

(28) Wilson, unpubl., version 1 and Wilson, unpubl., version 2.

(29) Drury, 112-79.

(30) Allaby, 55.
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Title Annotation:essay
Author:Flann, Christina
Publication:Traffic (Parkville)
Geographic Code:8AUST
Date:Jan 1, 2002
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