1963] 



BOTAXY OF THE GUAYAXA HIGHLANDS PART V 



213 



along the Rio Tirica (tributary to the Rio Caroni) to Chimanta Massif. In French 

 Guiana it is known from low altitudes in the vicinity of Cayenne and along the 

 Rio Maroni. 



The species are found in tall forest which is not inundated, most of the species 

 inhabiting the forests of low altitudes from slightly above sea level to 100 m. 

 Three species are found between 600-1600 m: K. neblinensis at 600-700 m, K. 

 longiloba at 1000 m, and K. montana at 1200-1600 m. The species are char- 

 acterized by various degrees of indument on the outer surface of the corolla-tube 

 of the staminate flowers. In K. sericantha the indument is densely sericeous with 

 relatively elongated hairs, whereas in the other species of the genus the hairs 

 are very short. In K. neblinensis, K. montana, K. duckei, and K. pahistris only 

 the basal 1-8.5 mm of the corolla-tube is glabrous, in K. longiloba the glabrity 

 extends up to 17 mm of the tube, in K. semisericea the glabrity extends up the 

 lower 25-50 mm of tube, while in K. insignis all the outer surface of the tube 

 is glabrous. 



Staminate flowers are known from all the species and are apparently the 

 ones more commonly collected. Pistillate flowering specimens are known only 

 from K. sericantha, K. pahistris, and K. insignis. In K. sericantha the staminate 

 flowers are fasciculate in umbelliform cymes and lack a common peduncle, 

 whereas in the other species of the genus the pedicels of the staminate flowers 

 are borne on a common peduncle of varying length. 



The pubescence on the lower surface of the leaf-blades is best developed in 

 the Peruvian K . montana and K. urophylla, the former ascending to an elevation 

 of 1200-1600 m. Various degrees of puberulence of the petioles and midribs and 

 lateral nerves of the lower leaf-surfaces are mainly encountered in K. pahistris 

 and K. sericantha. The corolla-tube is broader and the pedicels are stouter and 

 more strongly angled in K. sericantha than in the other species of the genus. 



Key to the Species of Kotchubaca 



1. Staminate flowers 6-merous, sessile or subsessile in subcapitate clusters; staminate 



calyx densely pilose. 7. K. urophylla. 



L Staminate flowers 7-10-nierous, obviously pedicellate in cymes, corymbose-cymes, or 

 umbels ; staminate calyx glabrous to puberulent. 

 2. Corolla-lobes (45-50 mm long) of staminate flowers manifestly longer than the 

 corolla-tube (22-35 mm long) ; calyx of staminate flowers with teeth 1.5—2 mm 

 ] ong; lateral pairs of nerves of leaf -blades 4-5. 9. K. longiloba. 



2. Corolla-lobes (15-41 mm long) of staminate flowers manifestly shorter than or 

 at most nearly equaling the corolla-tube (20-70 mm long) ; calyx of staminate 

 flowers without teeth or these only 0.2-1.2 mm long ; lateral pairs of nerves of 

 leaf -blades 5-18. 



3. Tertiary venation on lower surface of leaf -blades manifestly reticulate between 

 lateral nerves; calyx-tube of staminate and pistillate flowers granular- 

 rugulose and minutely puberulent without ; upper half of corolla-tube of 

 staminate and pistillate corollas mainly 5-12 mm broad, becoming 15-25 mm 

 broad at orifice; staminate pedicels fasciculate, not arising from a common 

 elongated peduncle. 1. K. sericantha. 



3. Tertiary venation obsolete or not manifestly reticulate on lower surface of leaf- 

 blades; calyx-tube of staminate and pistillate flowers glabrous or puberulent 

 without, not granular-rugulose ; upper half of corolla-tube of staminate and 

 pistillate flowers more slender, 2.5-6 mm broad, becoming 5-15 mm broad at 

 orifice ; staminate pedicels arising from a common elongated peduncle. 

 4. Corolla-tube (not including expanded throat) of staminate flowers externally 



glabrous throughout; pistillate corolla on peduncle 1-3 cm long. 10. K. insignis. 

 4. • Corolla-tube (not including expanded throat) of staminate flowers externally 

 gray- or buff-sericeous or tomentulose throughout or partly so. 



