NEILGHERRY PLANTS. 41
XXV.-RHAMNEÆ.
This is a family of considerable extent as regards the number of species and is very widely distributed over the world. De Candolle, in 1825, defined 230 species; and, if the increase has been in the same ratio as Celastrineae, we may with safety assume that it now includes 400 known species. Though most abundant in the lower latitudes of the temperate zones, it yet extends to near there extreme limits in both hemispheres but has not been found beyond. Within the tropics they are also numerous. This being, however, upon the whole, a more decidedly extra-tropical than Tropical family, it seems rather curious that so few species are found on the higher ranges of the Neilgherries. I can only at this time recollect three decidedly mountain species, two of Rhamnus and one of Scuttia the latter still undescribed and which I should have introduced here had I sooner become acquainted with it. This family was formerly combined with Celastrineae but is readily distin- guished by the form and position of the petals. Here they are small, scale-like, and placed immediately behind the stamens, not alternate with them as in Celastrineae. This is a character of greater value than might at first sight be supposed as it indicates that one series or row of stamens has been suppressed. In a regularly formed flower each series of parts is alternate with the one behind; hence, the petals are alternate with the sepals, the first row stamens with the petals, but opposite the sepals, the second row alternate with the sepals but opposite the petals. If the stamens are equal in number with the petals, and opposite to them; it indicates that the first row, which would have been alternate, is suppressed. This then, is the principal distinguishing mark between Rhamneae and Celastrineae, which are in other respects nearly related.
The affinities of these two orders are not by any means clear to me. That they are very nearly related to each other is certain: that they are nearly related to Terebinthaceae seems also certain. Lindley has, moreover, long insisted on the near relationship existing between them and Euphorbiaceae. That this order is related especially to Rhamneae is unquestionable, whether so closely as to entitle Euphorbiaceae to be placed between Rhamneae and Celastrineae is, to my mind, questionable; though, to be sure, it is small mat- ter which is first or last so long as really nearly related orders are brought together and formed into family groups in the manner attempted by Lindley in his alliances, and by Endlicher in his clapis.
In its economical relations this is, perhaps, a more important order than the preceding, though its properties are of very mixed and anomalous character. The berries of Rhamnes catharticus are a violently cathartic and under the name of Buckthorn were formerly employed a good deal in medicine. The juice of them made into a syrup is still occasionally so employed. The same juice mixed with a little alum and evaporated to a proper consistence affords the colour called sap green. As a contrast to that, the fruit of the Jujube tree Zizyphus Jujuba, is edible, so also are the succulent peduncles of the Hovenia dulcis a Chinese plant of this family, while the leaves of Segeretia Theezans another Chinese plant of the order, are used by the poorer classes there as a substitute for tea. lies in so natural a family are of rare occurrence. Such anoma-
