1840.] lAnnem Society. 53 



Read, " On the Heliamphora nutans, a new Pitcher Plant from 

 British Guiana." By George Bentham, Esq., F.L.S, 



The interesting subject of this communication was discovered by- 

 Mr. Schomburgk growing in a marshy savannah on the mountain of 

 Roraima, on the borders of British Guiana, at an elevation of about 

 6000 feet above the level of the sea. It belongs to the Sarraceniacece, 

 and constitutes a very distinct genus of that small but remarkable 

 family of plants, hitherto exclusively confined to the United States. 

 The genus is principally distinguished from Sarracenia by the entire 

 absence of petals, small apterous stigma, and trilocular ovarium. 



The following are the characters of this new genus : 



HELIAMPHORA. 



Perigonii foliola 4, 5, (vel 6 ?) hypogyna, libera, sestivatione valde imbri- 

 cata, subpetaloidea. Stamina numero indefinita, hypogyna. Antherce 

 oblongo-lineares, versatiles, biloculares, loculis oppositis iongitudinaliter 

 dehiscentibus. Ovarium triloculare, ovulis numerosis anatropis pluri- 

 serialiter placentae axili afRxis. Stylus simplex, apice truncatus. Stigma 

 parvum, obscure trilobum, minute ciliatum. " Capsula trilocularis, 

 trivalvis, polysperma" (Schomb.). Semina obovata, compressa, testa 

 fusca laxiuscula, vix rugosa, in alam fusco-membranaceum semen 

 cingentem expansa. Embryo parvus, teres, rectus, prope basin albu- 

 minis copiosi, radicula juxta hilum, cotyledonibus parvis. 



Hevha. perennis, uliginosa. Folia, radicalia; petiolus tubuloso-ampJiorce- 

 formis, ore obliquo margine subrevoluto. Scapus erectus, apice simpli- 

 citer racemosus, glaber. Flores nutantes, albi v. pallide rosei. 



1. H. nutans. 



Read a paper, entitled " On the Structure of the Tissues of Cy- 

 cadece," By D. Don, Esq., Libr. L. S., Prof. Bot. King's College. 



In Coniferce the structure of the stem presents the ordinary appear- 

 ance of dicotyledonous trees ; the annual layers are distinctly 

 marked, and there is a regular bipartition of each into wood and bark 

 (liber) ; but in Cycadece no bipartition takes place of the fibro-vascular 

 bundles, which in that respect resemble those of monocotyledonous 

 plants, and the differences otherwise are very striking, Cycas having, be- 

 sides a large central pith, several thick concentric alternating layers 

 of celMar and fibro-vascular tissue ; and in Zamia and Encephalartos, 

 besides the pith, there are only two very thick layers, one of fibro- 

 vascular, and the other, which is also the exterior one, of cellular 

 tissue. The great peculiarity of the Coniferce, and which distin- 

 guishes them as well from Cycadece as from every other family, is 

 the remarkable uniformity of their woody tissue, which consists of 



