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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [Vol. 9, No. 3 



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condition is shown by two other collections, Schultes and Pires 9114 from the 

 Rio Vaupes, and Holt and Blake 595 from the Rio Negro, both localities being in 

 Brazil. This is the first record from Venezuela, the species being known also 

 from British Guiana and Suriname as well as from Amazonian Brazil. 



Arrabidaea trailii Sprague; Sandwith, Kew Bull. 1953:461. Jan 1954. 



VENEZUELA: Bolivar; high-climbing woody vine, spectacular in flower, calyx 

 dull red, corolla deep red, southwestern-facing slopes of Chimanta-tepui* above 

 valley of Rio Tirica, 1000-1700 m, May 16, 1953, /. A. Steyermark 75421. Ama- 

 zonian Brazil. The first record for Venezuela. 



A very robust climber with large leaflets and dense trusses of small, deep red 

 corollas. The fruit and seeds may now be described from the material of Steyer- 

 mark 15421 and Herb. Jard. Bot. Rio de Janeiro 35630 (coll. Ducke): capsule 

 narrowly elongate-linear, narrowed to the apex, up to 27 cm long, 1-1.2 cm broad, 

 the valves densely minutely lepidote, with somewhat thickened margins and con- 

 spicuously raised, thin and sharp, median nerve; seeds traversely oblong, 8-9 mm 

 long, 3-4 cm broad, the body dark brownish-lead-coloured, the wings membranous 

 and whitish-hyaline. 



Digomphia densicoma (Mart, ex DC.) Pilger. 



I have by now studied 24 gatherings of this species, which apparently has a 

 wider distribution than D. laurifolia, being found at altitudes of from 500 to 2100 

 m in the Upper Mazaruni River region of the Pakaraima Mts. in British Guiana, in 

 Venezuela (on the tepuis of Estado Bolivar, apparently less common than D. 

 laurifolia; on the cerros of Territorio de Amazonas, evidently much more frequent 

 than D. laurifolia), and also in northwestern Amazonian Brazil and in Amazonian 

 Colombia where D. laurifolia has not yet been collected. As with D. laurifolia 

 there is remarkable variation in the size and shape of the leaflets, and in the size 

 of the calyx and capsule. Moreover, the species varies in habit, from a small 

 shrub of 3 ft to a forest tree 50-80 ft high with a trunk 1-1% ft in diameter. 

 Nevertheless, I am unable to distinguish any of the specimens even as a variety, 

 much less as a distinct species. Variation in the leaflets between individuals 

 from one small area is particularly well shown in the four collections from the 

 Cerro Sipapo (Paraque). Specimens from the eastern end of the range, in British 

 Guiana, have the largest and broadest leaflets, while those at the western end, 

 in Amazonian Colombia, have leaflets of the smallest and narrowest type. The 

 color of the corolla varies from lavender or light pink to white. In my account of 

 this family in Dr. Steyermark's "Contributions to the flora of Venezuela"* I 

 referred his Ptari-tepui* material to D. densicoma with some doubt, but the diffi- 

 culty of the calyx character is now cleared up by the numerous recent collec- 

 tions from so many localities. The calyx is at first entire, and then splits bi- 

 laterally into 2 or sometimes 3 broad lobes. At this stage the pressed calyx 

 sometimes appears spathaceously split down one side only. Later, the two broad 

 lobes become themselves deeply divided, so that eventually there are four sub- 

 equal lobes. When there are three original lobes, the third of these remains un- 

 divided with the result that there are five subequal lobes at the final stage. 

 D. densicoma, which is presumably the ancestor of D. laurifolia, is always dis- 

 tinguished from it by the pinnate leaves and by the relatively longer and narrower, 

 less elliptic, capsule. 



Unpublished as this goes to the printer. 



