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MEMOIRS OF THE NEW YORK BOTANICAL (JARDEX 



VOL*. 10 



The first three collections cited above have the leaves of a firmer texture 

 than is usual for the species, suggesting P. cayennensis (A. DC.) Pichon. The 

 anthers are glabrous on the back, not reaching up to the faucal annulus ; the 

 epistaminal appendages are short. The mericarps {34991, 37529) are, as in 

 /'. acutifolia^ typically agglutinated and puberulent, unlike those of P. cayen- 

 nensis. P. acutifolia, as interpreted at the present time, has a vast range, extend- 

 ing from Central America or Mexico to Argentina. It is quite variable, and its 

 limits of morphological variation are not clearly defined. There is a likelihood 

 that it will eventually be submerged in P. quinquangularis (Jacq.) Spreng., for 

 the characters invoked to separate the two are not too convincing. Incidentally, 

 the XYBG sheet (flowers poor, corolla lacking) of Maguire <(• Fanshawe 23351 

 from the Kaieteur Plateau in British Guiana, cited as P. perplexa Woods, in 

 Bull. Torrey Club 75: 556 (1948), appears to be P. cayennensis. In previous works. 

 Echites leptoloba Stadelm., originally described from the Rio Negro in Brazil, 

 has been curiously placed in the synonymy of P. agglutinata (Jacq.) Woods., 

 an Haitien species that has never been reported from South America. The de- 

 scription of Stadelm eyer's species better suggests P. acutifolia. 



Rhahdadenia macrostoma (Benth.) Muell.-Arg. 



Wurdack 4' Monachino 41391, Apure, occasional in riverine tangle between Rio Orinoco 

 and Piedra La Villa (opposite Raudal Marimare), elev. 80-90 m, Jan 1^7, 1956, herbaceous 

 vine with white latex, flowers brilliant red. 



The seeds of this species are now known. They are light brown, glabrous 

 (microscopically puberulent), terete-linear and gradually tapering to a tri- 

 angular beak, 2.3 cm long, 1.3 mm broad, the beak about 0.3 mm thick near the 

 apex, the coma silky pale-tawny } about 3 cm long. The plant cited above is 

 almost glabrous; the sepals are erect, up to 5-7 long. The material identified 

 as R. pohlii Muell.-Arg. from north of the Amazon basin is hardly specifically 

 different from our plant. The pilosity of the plants and even the length of the 

 sepals, characters used to distinguish this species, are not reliable. For example, 

 one of the two sheets at The New York Botanical Garden of Busby & Squires 

 20 (lower Orinoco, Sacupana), cited as R. pohlii by Woodson, contains a speci- 

 men with a glabrous stem, the other a stem clearly pilose. The sepals are up 

 to 10 mm in length. It is likely that the pilose material corresponds to R. macro- 

 stoma a pubescens Muell.-Arg. (Linnaea 30: 435. 1860), a name not accounted 

 for in Vyoodson's monograph. 



