262 OBSERVATIONS ON PLANTS 



several require material alterations, some of which suggest 

 obsei'vations relative to the structure and arrangement of 

 the natural order. 



Savignya /Egyi'tiaca [Be Cand. 8i/st. 2, p. 283) is 

 the first of these. It was observed near Bonjem by Dr. 

 Oudney, whose specimens slightly differ from those which 

 I have received from M. Delile, by whom this plant Avas 

 discovered near the pyramid of Saqqarah, and who has 

 well figured and described it in his ' Flore 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, has remarked,^ 

 that Savignya of De CandoUe possesses no characters suffi- 

 cient to distinguish it as a genus from Lunaria ; and still 

 more recently, Professor Sprengel has referred our plant 

 to Parsetia.^ The genus Savignya, hOVever, will no doubt 

 be ultimately established, though not on the grounds on 

 which it was originallv constituted : for the umbilical cords 

 certainly adhere to the partition, the silicule, which is never 

 sii] 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 relied 

 on the external characters of the seed, principally on its 

 great compression, its broad margin or wing, and on the 

 wdiole 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- 

 rorhizEe and Notorhizse, employed by M. De Candolle to 

 express the two principal modifications of cotyledons in 

 CrucifeiEe, appear to me so far objectionable, as they may 



' flora Libyccn Hpecim. p, 35, - Sysl. VerjeUib. p. 871. 



