1953] 



BOTANY OF THE GUAYANA HIGHLAND 



109 



It has been frequently stated that this region of southern Venezuela often 

 shows a remarkable floristic affinity with the Rio Negro region, and this novelty 

 supports such contentions, as do examples discussed elsewhere in this report. 



8. Aldina macrophylla Spruce ex Bendi.; Mart, Fl. Bras. 15(2): 13. 1870. 



Tree to 17 m. tall, the vegetative parts except the upper leaflet surface ap- 

 pressed-puberulent; leaves 3-foliolate, the rachis 4 cm. long, the petiolules in- 

 crassate, finely corrugate transversely, 13 mm. long, the blades oblong, 21-22 

 cm. long, 8.5-9.5 cm. wide, the base rotund, the apex short-acuminate, the upper 

 surface glabrous, nitid, with 12-16 pairs of primary veins barely prominulous, 

 below subglaucous, with primary veins prominulous; inflorescence a sparsely- 

 branched panicle 20-30 cm. long, fulvo-puberulent, the pedicels 3-7 mm. long, 

 the mature buds about 1.5 cm. long, ellipsoid; calyx densely fulvo-puberulent 

 outside, sparsely flexuose-villose inside; petals 4, oblanceolate, 2-2.5 cm. long, 

 1 cm. wide; stamens glabrous, the filaments 2 cm, long, the anthers 7 mm. long, 

 0.6 mm. wide; stigma simple; style straight, 3.5 mm. long; ovary oblong-elliptic, 

 5 mm. long, 1.8 mm. wide, glabrous, 5-7-ovulate, the stipe slender, densely ap- 

 pressed-puberulent, 4 mm. long; fruit unknown. 



Specimens Fxamined: "Ad flumina Casiquiari, Vasiva et Pacimoni," Spruce 

 3349 (type no.; NY). 



The glabrous character of the ovary in this species is found elsewhere only in 

 the preceding species, A. yapacanensis, from which it differs in having much 

 larger and differently shaped leaflets. Also the inflorescence here is twice as 

 long sometimes and only sparingly branched while in that species it is shorter 

 and regularly branched. 



9. Aldina occidentalis Cucke, Arch. Inst. Biol. Veg. [Rio de Janeiro] 4: 16. 1938. 

 Large tree, the vegetative parts granular-puberulent; leaves (3-)5(-7)-foliolate, 



the petioles 3-5-5.5 cm. long, the rachis 3.5-4 cm. long, the petiolules 5-8 mm. 

 long, verrucose-corrugate, the blades oblong-oval, 7.5-8.5 cm. long, 3*5-4.5 cm. 

 wide, the base rotund, the apex rounded and retuse, the upper surface glabrous, 

 nitid, the venation prominulous, the lower surface minutely pruinose-lepidote and 

 pubescent, the hairs minute, weak, collapsed in drying, erect when living, about 

 10 pairs of primary veins subsalient below and the veinlets prominulous; inflores- 

 cence terminal, laxly paniculate, to 28 cm. long, densely fusco-fulvo-puberulent, 

 the pedicels 1-3 mm. long, the mature buds about 1 cm. long; calyx about 8 mm. 

 long, split into about three uneoual parts, densely cervino-puberulent; petals 6, 

 in the immature flower 1.8 cm. long, 1.2 cm. wide, obovate-obcuneate, white; sta- 

 mens glabrous, the filaments about 1 cm. long, united at the base, the anthers 5 

 mm. long, 0.5 mm. wide; style glabrous, 2.5 mm. long, straight; stigma simple; 

 ovary oblong, 5 mm. long, 2 mm. wide, brunneo-sericeous, 4-ovulate, the stipe 

 glabrous, about 1 mm. long; fruit unknown. 



Specimens Fxamined: "Sao Paulo de Olivenca (Rio Solimoes, civ. Amazo- 

 nas)," Ducke H.J.B.R. 24051 (isotype; US). 



Ducke related this species to A. heterophylla; the inflorescence and small 

 buds of both does perhaps indicate some relationship. However, the leaflets of 

 A. heterophylla are completely glabrous and the type of pubescence of A. oc- 

 cidentalis is found in only one other group, A. insignis var. retusa. The great 

 difference in the size of the buds and flowers of these two groups is sufficient 

 for their separation. 



10. Aldina heterophylla Spruce ex Benth.; Mart, Fl. Bras. 15(2): 13. 1870. 



Tree 20-30 m. tall, all parts except the inflorescence glabrous; leaves 1-3" 

 foliolate, the petioles 5-45 mm. long, the rachis 5-12 mm. long, the petiolules 6- 



