Page:A Voyage to Terra Australis Volume 2.djvu/570

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556
APPENDIX.
[Botany of Terra Australis.

The species of Euphorbia are not numerous in Terra Australis, most of them are intratropical plants, and all of them are referable to one section of the genus. It appears to me that the name of the order ought not to be taken from this genus, which is so little calculated to afford a correct idea of its structure that authors are still at variance in the names and functions they assign to several parts of the flower. The view I take of the structure of Euphorbia is, in one important particular at least, different from those given by Lamarck,[1] Ventenat,[2] Richard?[3] and Decandolle,[4] though possibly the same that Jussieu has hinted at;[5] so briefly, however, and I may add obscurely, that if his supposition be really analogous to what I shall presently offer, he has not been so understood by those who profess to follow him in this respect.

With all the authors above quoted, I regard what Linneus has called Calyx and Corolla in Euphorbia as an Involucrum, containing several male flowers which surround a single female. By some of these authors the male flowers are described as monandrous, and in this respect, also, I agree with them; but the body which all of them describe as a jointed filament, I consider to be made up of two very distinct parts, the portion below the joint being the footstalk of the flower, and that above it the proper filament: but as the articulation itself is entirely naked, it follows that, there is no perianthium; the filiform or laciniated scales, which authors have considered as such, being on this supposition analogous to bracteæ; The female flower, in conformity with this supposition, has also its pedunculus, on the dilated, and in a few cases obscurely lobed, apex of which the sessile ovarium is placed. If this be a correct view of the structure of Euphorbia, it may be expected that the true filament, or upper joint of what has commonly been called filament, should, as in other plants, be produced subsequent to the distinct formation of the anthera, which consequently will be found at first sessile on the lower joint or peduncule, after that has attained nearly its full length; and accordingly this proves to be the case in such species as I have examined. Additional probability is given to this view by the difference
  1. Encyclop. botan. 4. p. 413.
  2. Tableau, 3. p. 487.
  3. In Michaux, fl. bor. amer. 2. p. 209.
  4. Flor. Franc. 3. p. 329.
  5. Gen. pl. 386.