STAPELTE^E OF TIIUNBERG's HERBARIUM. 168 



specimen in spirit at the British Museum, another in spirit at 

 Kew sent by Sir Henry Barkly, and two living plants sent home by 

 the same gentleman which flowered last year : in this plant there 

 is a distinct outer corona, the lobes of which are connate in a cup, 

 and aduate to five dorsal tooth-like projections from the lobes of 

 the inner corona ; besides this, S. punctata and S. pulla differ 

 widely in habit, as may at once be seen on glancing at Masson's 

 figures. The year after R. Brown's paper was published, Haworth 

 published his ' Synopsis Plantarum Succulentarum,' wherein we 

 find he has placed only S. pulla in the genus Piaranthus, and S. 

 punctata, together with S. decora and S. geminata, Mass., he places 

 in his new genus Obesia ; and here he is right ; for these three 

 species are undoubted congeners : but the characters of Obesia 

 are exactly those of Piaranthtis -, therefore as the latter genus 

 claims priority, and the Obesice are the only plants that agree with 

 the character on which it was founded, Obesia must rank as a syno- 

 nym of Piaranthus. Matters have been further complicated, first 

 by the erroneous description of Obesia given by Decaisne in 

 DeCandolle's Prod. viii. p. 661 ; secondly, by Mr. Bentham, in the 

 * Genera Plantarum,' having placed it as a synonym of Podanthes, 

 from which it materially differs in wanting the outer corona pos- 

 sessed by that genus, Podanthes being closely related to Stapelia 

 § Orbea ; and it must, I think, only constitute another section of 

 that heteromorphic genus. I here add emended characters of the 

 genus Piaranthus. 



PiakaxTuus, E. Brown (non alior.).— Obesia, Haw. 



Calyx 5-partitus, basi intus 5-squamatus. Corolla rotata vel campa- 

 nulata, alte 5-fida. Corona simplex (exterior deest), 5-loba, lobis 

 dorso dentato-cristatis. — Herbse Africae australis, carnosa;, Duvali- 

 arum habitu. 



Hie pertinet P. punctatus, R. Br. ; P. decorus, Mass. ; P. geminatus, 

 Mass. ; P. serrulatus, Jacq. 



Stapelia mammillaris, L. (S. pulla, Mass.), I propose to place 

 for the present in the genus Boucerosia, of which, with a few 

 other species, it will form a section, characterized by the narrow 

 corolla-lobes, included gynostegium, and stems armed on the 

 angles with stout spine-like teeth. I prefer this rather than erect 

 it into a new genus ; for, from the material at Kew, it is evident 

 that either a number of very closely allied genera will have to be 

 established, which is undesirable, or the forms must be grouped 

 into sections under one genus. 



