Page:Miscellaneousbot01brow.djvu/280

 262 OBSERVATIONS ON PLANTS

several require material alterations, some of which suggest observations relative to the structure and arrangement of the natural order.

Savignya iEcYPTiACA [De CancL Sj/st. 2, p. 283) is the first of these. It was observed near J3onjem by Dr. Oudney, whose specimens slightly differ from those which I have received from ]\L Delile, by whom this plant was discovered near the pyramid of Saqqfirah, and who has well figured and described it in his ' More d'Egypte,' under the name of Lunaria parviflora. By this name it is also published by M. Desvaux. Professor Viviani, in giving an account of his Lunaria libyca, a plant which I shall presently have occasion to notice more particularly, lias remarked,^ that Savignya of De Candolle possesses no characters suffi- cient to distinguish it as a genus from Lunaria ; and still more recently, Professor Sprengel has referred our plant to Farsetia.^ The genus Savignya, lio\Yever, will no doubt be ultimately established, though not on the grounds on which it was originally constituted ; for the umbilical cords certainly adhere to the partition, the silicule, which is never 211] absolutely sessile, is distinctlypedicellatedinDr. Oudney's specimens, the valves are not flat, and the cotyledons are decidedly conduplicate. In describing the cotyledons of his plant as accumbent, M. De Candolle has probably rehed on the external characters of the seed, principally on its great compression, its broad margin or wing, and on the whole of the radicle being visible through the integuments. It would appear, therefore, that the true character of the cotyledons of Savignya has been overlooked, chiefly from its existing in the greatest possible degree. To include this degree of folding, in which the margins are closely approxi- mated, and the radicle consequently entirely exposed, a definition of conduplicate cotyledons, somewhat different from that proposed in the ' Systema Naturale ' becomes necessary. I may here also observe, that the terms Pleu- rorhizos and Notorhiza?, employed by M. De Candolle to express the tvro principal modifications of cotyledons in Crucifera% appear to me so far objectionable, as they may

1 Florcs Lii^ca Specim. p. 33. - S^'ni. Ve^jelah. jf), 871.

��i

�� �