Page:Flora Australiensis Volume 5.djvu/328

From Wikisource
Jump to navigation Jump to search
This page has been validated.
316
CIV. PROTEACEÆ.

thin, rarely coriaceous or hard; embryo straight, with fleshy cotyledons and a short inferior radicle.—Shrubs or trees, rarely undershrubs or even perennial herbs. Leaves alternate or scattered, in a very few genera strictly, opposite or verticillate, but often crowded under the inflorescence so as to appear verticillate, usually coriaceous, often vertical with stomata on both sides, or in the same genera horizontal or narrow and terete, entire toothed or variously divided, without stipules. Flowers axillary or terminal, solitary or in racemes or spikes, often condensed into umbels heads or cones, each flower or pair of flowers subtended by a bract, very deciduous in some genera and perhaps sometimes really deficient, the pedicels always without bracteoles.

Proteaceæ, with their chief seat in Australia and South Africa, extend on the one hand to New Caledonia, the Indian Archipelago, and tropical Asia, chiefly eastern, to Japan, and on the other to South America. The seven tribes of the Order are all in Australia. Of tha first four, constituting the Nucamentaceæ, the two principal ones, Proteeæ and Personiæ, are also in South Africa, but represented by different genera, the nine Australian ones being, as well as the four constituting the small tribes Conospermeæ and Franklandieæ, all endemic with the exception of a single New Zealand species of Persoonia, and a New Caledonian Canarrhenes. None of the Nucamentaceæ are either in America or Asia, for the South American Andripetalum and Guevina, referred by Meissner to Persoonieæ, belong with Helicia and Macadamia to the Grevilleæ. Of the Australian genera of this tribe of Grevilleeæ, Helicia is chiefly Asiatic, Adenostephanus is tropical American, with one New Caledonian species, and the large genus Grevillea has also a few New Caledonian species, the remaining eight genera are endemic. Of the Australian Embothrieæ, Lomatia extends to the Andes of South America, where it is accompanied by two nearly allied genera, and Stenocarpus to New Caledonia; the two remaining genera, as well as the two which constitute the tribe Banksieæ, are endemic in Australia.

The clavate fusiform or disk-shaped end of the style in Proteaceæ is usually described as the stigma, and when it is more or less constricted it is said to be articulate, but I have never found any real articulation, and although the thickened style-end may be an essential aid in the collection or dissemination of the pollen, its surface is not stigmatic, the real stigma being usually very small, either on the point terminating the style-end; or in the centre of the disk, or quite lateral. The diversified mode in which in different genera the conformation of this style-end and its relation to the anthers promotes the dissemination of pollen whilst it impedes self-fertilization, upon which I have drawn up a few notes for the Linnean Society founded on the examination of dried specimens, would be an interesting study for local botanists who have the means of examining and watching the plants living in their native stations.

In the distribution of the numerous species of this most natural Order into tribes, genera, and sections, I have only had to follow, with slight modifications, the admirable arrangement proposed by Brown and further developed by Endlicher and Meissner; but in the great subdivision into Nucamentaceæ and Folliculares, these terms most not be taken strictly in their literal sense, for indehiscent drupes occur in both divisions. Taking however the fruit generally, in conjunction with the arrangement of the ovules and the inflorescence, neither of them again strictly constant, we have very fairly definite characters for two large groups which are both natural and to a certain degree geographical. For although both are abundant in Australia, the Nucamentaceæ alone are in Africa, and the Folliculares alone in Asia and America.

Suborder 1. Nucamentaceæ.Fruit an indehiscent nut or drupe. Flowers usually solitary within each bract.

Tribe 1. Proteeæ.Anthers all perfect or very rarely the upper one abortive, with 2 parallel cells adnate to the connectivum, inserted at the base of the short spreading laminæ of the perianth. Ovule 1 or rarely 2. Stigma terminal. Fruit a dry nut.