abundance, and exists, though much more sparingly, within the tropic.
Restiaceæ are almost equally numerous at the Cape of Good Hope as in the principal parallel of New Holland. One species only of the order has been observed in New Zealand, and hitherto none in South America.
CYPERACEÆ. In Terra Australis this is a very extensive order, consisting already of more than 200 species. It contains, however, fewer peculiarities in structure than several other orders that are much less numerous. Its maximum appears to be in the principal parallel; but the species observed solely within the tropic exceed one third of the whole number. Cyperaceæ, in many respects, are nearly related to Restiaceæ, and when furnished with a true perianthium are distinguishable from the monospermous genera of that order, solely by the different position of the embryo in the seed. But in the greater part of the order the perianthium is either entirely wanting or merely setaceous. Fuirena, Lepidosperma and Oreobolus, all of them natives of New Holland, are almost the only genera in which it is found of nearly the usual appearance.
What I have formerly termed perianthium in Carex, Diplacrum, and Schœnus nemorum, ought, perhaps, rather to be considered as internal bracteæ, analogous to those of Lepyrodia, of Irideæ, and, perhaps, to the upper valve of the inner envelope of grasses.
I have formerly remarked that the Perianthium of Hypœ- 580] lyptum consists merely of the squamæ of a spicula, similar to that of Kyllinga, but reduced to two valves.
GRAMINEÆ. This order comprehends, at least, one fourth of the whole of Monocotyledones, and in Terra Australis, where upwards of 200 species have already been observed, it bears the same proportion to that primary division.
I have formerly, in arranging the Australian genera of Gramineæ, endeavoured to explain what I conceived to be the natural subdivision of nearly the whole order into two
