22 



MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



[VOL. 10 



Sepals commonly 6, sometimes 8, paired and decussate, or less commonly 9 or 

 10, and then the upper imbricate ; petals 5 ; synandrium pentagonal and col- 

 umnar, or somewhat hemispheric, the filaments prismatic, connate, the anthers 

 distal, depressed, annular or discoid; in the male flowers no vestige of a pistil 

 present ; in the female flower the anthers commonly 1-3-seriate and probably 

 mostly functional ; ovary 5-locular, the endocarp cartilaginous, commonly be- 

 coming strongly rugose at maturity ; terrestrial shrub or small tree ; latex clear, 

 scanty. 



Type species: Clusia eugenioides PI. & Tr. 



Key to the Species of Clusia sect. Omphalanthera 



1. Pistil and fruit strongly rostrate. 

 2. Leaves strongly petiolate. 



3. Corolla large, the petals 20-30 mm long; leaves elliptic-oblanceolate to oblan- 

 ceolate, or elliptic-oblong, 10-15 cm long, 5-10 cm broad ; fruit globose, to 3 cm 

 long; stigmas sessile on the summit of the ovary; widely distributed in the 

 valleys of the Alto Orinoco, Rio Negro, and the Magdalena Valley of Venezuela 

 and Colombia. 1. Clusia columnaris. 



3. Corolla small, the petals 12 mm or less long; leaves elliptic to elliptic-oblan- 

 ceolate, 10-15 cm long, 4-6 (7) cm broad; fruit narrowly oblong, 15-20 cm 

 long; stigmas borne on discrete styles 0.5-1.5 mm long; confined to the Rio 

 Pacimoni drainage, Amazonas, Venezuela. 2. Clusia gratula. 



2. Leaves sessile or essentially so; Upper Rio Orinoco-Ventuari, Amazonas, Vene- 

 zuela. 3. Clusia annularis. 

 1. Pistil and fruit not rostrate; leaves strongly petiolate. 



4. Branchlets quadrangular ; leaf -blades broadly elliptic to elliptic-obovate, 10-15 

 cm long, 6-8 cm broad. 

 5. Sepals 3 (4) pairs, decussate; mature fruit obpyriform; plants of the sandstone 



area of the Guayana Highland, Venezuela. 4. Clusia brachystyla. 



5. Sepals 9-10, the lower paired and decussate; mature fruit elliptic-oblong; plants • 



of Pacific coastal region, Colombia. 5. Clusia densinervia. 



4. Eranchlets terete; leaves spathulate-oblanceolate, 7-11 cm long, 3-6 cm broad; 



plants of the Colombian Andes. 6. Clusia eugenioides. 



1. Clusia columnaris Engl. Fl. Bras. 12 1 :432. 1888. 



Type: in fissuris rupium ad San Gabriel do Cachoeira ad Rio Negro, 

 provincia do Alto Amazonas, Spruce 1980 (G, two sheets; K; M; photos at NY.) 



C. cotnmnaris is widespread and somewhat variable in riparian and savanna 

 and rock outcrop ecotone habitats in the basin of the Alto Orinoco, the Rio 

 Negro, and the Magdalena. The review of some 100 sheets at The New York Bo- 

 tanical Garden has failed to demonstrate any clearcut geographic or ecologic 

 varietal segregation. 



Cuatrecasas (Rev. Acad. Colomb. Ci. 8: 41. 1950) has described two varie- 

 ties, viz. : C. columnaris Engl." var. magdalenensis Cuatr. from the Magdalena 

 Valley, Colombia, H aught 1366 (holotype F, isotype NY) ; and C. columnaris 

 Engl. var. vaupesana Cuatr., .from Circasia, Rio Vaupes, Colombia, Cuatrecasas 

 7166A (holotype, F) ; and Rio Guayabero, Cuatrecasas 7555 (paratype, F). We 

 have not been able to study sufficiently adequate series of specimens from these 

 areas to enable us to make a critical judgment on the distinctness of these 

 varieties. 



