DE. T. ANDERSON OX SPHJEUOCOMA. 15 



ovoidea ? ; seminibus compressis, testa Crustacea grosse lacunosa. 

 Frutex ramulis robustis ferrugineo-pubescentibus, utrinque linea 

 elevata bases foliorum connectente notatis ; foliis alternis, brevi- 

 petiolatis, oblongis, subacutis, crenulatis integerrimisve, utrinque 

 glabris ; petiolo crasso ; stipulis ? ; floribus majusculis ; axillis 

 foliorum 2-k subsessilibus, braeteis magnis imbricatis late ovatis 

 acutis primo immersis ; calyce sericeo. 



Barteria Nigritana. 



Hab. Ad ripas flum. Nun (ostium Nigritis), legit beat. Barter. 



Frutex robustus, habitu Smeathmannia ; foliis 6-10" long., 2-3" lat., 

 nervis primariis numerosis. Stipula deciduae, non visae. Flores 

 sessiles, circiter 1-1 V diametro, iis Smeathmannice subsimiles. Bracteee 

 numerosae arete imbrieatae, alabastrum maturum velantes, late ovatae 

 cuspidato-acuminatse. Petala calyce paulo longiora. Stamina per- 

 pluriraa. Ovarium glaberrimum. Fructus magnit. ovi columba>. 



Tab. II. fig. 1, flower with the bracts removed ; 2, flower laid open ; 3, 

 stamen; 4, transverse section of ovary ; 5, seed. All magnified. 



On Sph&rocama, a new Genus of Oaryophyllea?, from Aden in Arabia 

 Felix. By Thomas Anderson, Esq., M.D., F.L.S. 



[Bead March 1, I860.] 



My attention was directed to this plant while examining the 

 Hookerian Herbarium for materials for a Florida of Aden. As it 

 has proved to be a new genus of Caryopliyllece possessing many 

 points of interest, I have had a figure and dissections of it made 

 for the Society's Journal. 



Its distinct sepals, well-marked petals, and five almost perigy- 

 nous stamens opposite the sepals, unilocular bi-ovulated ovary, 

 with the placenta prolonged beyond the insertion of the ovules, 

 place it in the tribe Alsinece. 



Forskal's genus Oymnocarpos is its nearest ally, and is very 

 like it in habit ; but the two ovules and bifid stigma of SpJuero- 

 coma readily distinguish it from that genus. It resembles 

 E. Brown's PterantJius in the sterile flowers having accrescent 

 calyces, forming in fruit setaceous heads ; but from the two genera 

 Cometes and PterantJius, forming that tribe, it differs in having the 

 seta of the sepals undivided, as well as in the shape of the embryo, 

 which is curved over the albumen in Sphcerocoma, while in Pte- 

 rantJius it is placed at one side. 



It is evidently a rarr plant, as it occurs in no collection except 



