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 OF PLANTS CALLED COMPOSITE. 301

plants sufficiently dissimilar in habit and structure to justify a further subdivision ; and, what is remarkable, none of them entirely agreeing with his generic character.

The first tribe consists of herbaceous plants, natives of Europe and North America, having the male and female flosculi in distinct involucra and on different individuals. To this genus the name Antennaria 1 may remain, though

1 Antennaria. Antennarise species. Gartner. Gnaphalii species. Linn. Jussieu.

Involucrum imbricatum, scariosum, coloratum. Receptaculum epaleafcum, scrobiculatum. Flosculi dioici. Masculi : antheris basi bisetis : stigmalibus truncatis : Pappo vel penicillato v. apice incrassato. Feminei filiformes, limbo parvo : slaminum rudimeutis nullis : Pappo capillari.

Herbse perennes, tomentosa, incanm. Folia plana, adulta sape super gla- briuscula ; radicalia in plerisque latiora. Inflorescentia corymbosa rarb soli- taria. Iuvolucri turbinati vel quandoque liemispharici squama e basi calychui superne colorata (alba v. purpurascentes). Corullula? Jlava. Antherse semi- exserta. Pappus marium niveus, opacus.

Obs. Gnaplialium margaritaceum, which I have referred to this genus, was first described by Clusius ; from whose account it appears to have been intro- duced into the English gardens from America towards the end of the sixteenth century.

It has ever since been very generally cultivated, as an ornamental plant, both in this country and on the continent of Europe ; and has a place in several of the European Floras, as well as in those of North America. It is surprising, therefore, that hitherto the male plant only should have been observed, uni- formly, however, considered as hermaphrodite, except by M. Cassini, who in his first memoir on Synanl/iera (in Journal de Physique, tome lxxvi, p. 200) sus- pects it to be male, from the imperfect appearance of the ovarium.

That this species of Gtiaphalium is really dioecious, I learned several years ago from an inspection of a specimen of the female plant in the Herbarium of Sir Joseph Banks, who found it on the banks of the Hymney in Glamorgan- shire, where the plant was first observed by Lhwyd. I have since received several specimens of both sexes from Mr. Bicheno, to whom I had mentioned this fact, and who obligingly undertook to observe the different states of the plant in the same place, where it seems to be really indigenous. I have never been able to discover any female florets in the circumference of the capitulum of the male plant ; but in the centre of the female capitulum I have always found two or three imperfect male florets, whose antherae, although cohering and of the usual form, appear to be destitute of pollen.

The separation of sexes in a still more common plant of this class, namely, Serratula tinctoria, has been equally overlooked.

All the authors who have noticed this species, which is included in almost every European Flora, as well as in more than one recent Monograph of the genus, have considered it as hermaphrodite, while it really belongs to Poly- gamia dicecia, or has its perfect sexual organs on different plants. The herma- phrodite plant, apparently perfect, but which I believe very seldom ripens seed, is well figured by Schkuhr (in Botanisches Handbuch, tab. 234) ; and the female, whose stigmata are remarkably developed and undulated, while the

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