150 



[TAB. XLIII. XLIV. XLV.] 



ON THE SPECIES OF THE GENUS COLLETIA, 

 OF THE NATURAL ORDER RHAMNE^, 



Discovered by Dr. Gillies in South America. 



The genus Colletia, named by Commerson in honour of his 

 countryman Collet, a botanist who, we are informed, studied 

 the plants of Bresse, and proved a great opponent to the sys- 

 tem of Tournefort, was established in the Genera Plantarura 

 of Jussieu, I believe upon the C. spinosa, Lam., (C, horrida, 

 Willd.) a native, it is said, of Brazil, Chili, and Peru: and 

 the main character is made to depend, according to Jussieu, 

 Lamarck, Willdenow, and in part, De CandoUe, upon the 

 campanulate perianth or calyx having 5 plic(B internally, 

 which are squamiform; yet the C. spinosa presents nothing 

 of this kind, nor has any species of the genus that has come 

 under my observation. Kunth,* too, who has examined 

 Jussieu's own specimen, expressly says, that he " could not 

 detect the plicae mentioned by Jussieu," but he observed 

 within, an " annular, narrow, fleshy, entire disc, reflexed and 

 glabrous, inserted above the base of the calyx," exactly as I 

 find in all Dr. Gillies's undoubted species of CoUetia. 



Ventenat, in his Jardin de Cels, added C. obcordata, and 

 in his Choix de Plantes, C. ser?'ati/olia, and C. Ephedra; all, 

 as well as C. horrida, having opposite spinous branches and 

 few or no leaves, together with campanulate flowers; but 

 these, except C. serratifolia, M. Kunth thinks should consti- 

 tute a peculiar genus, on the one hand allied to CoUetia and 

 Rhamnus, on the other to Ceanothus, differing from the true 

 Colktice in the presence of petals, antl in the absence of a 

 disc. Hence that author excludes from his generic character 

 the 5 squamiform plica3 to the calyx and the petals, and de- 

 fines the disc as above in describing that of C. horrida : " Dis- 

 cus annularis, angustus, carnosus, integer, calyce supra basin 



* Nov. Gen. V. 7, p. 46. 



