Species of African Simuliidae. 75 



the first branch divides dorsad into three short branches 

 progressively longer ; the second main branch divides dorsad 

 into four, the first very short, the remainder progressively 

 longer; the third main branch divides into two. 



The pupa was determined from the genitalia and legs of 

 the adult male, dissected from the pupa and compared with 

 the type. 



Simulium gilvipes, sp. n. 

 (PI. III. fig. 5 ; PI. IV. fig. 1.) 



Male. — Length 24 mm. 



Antenna entirely dark brown, with greyish pubescence, 

 the two basal joints somewhat paler. Thorax velvet-black, 

 covered with thick light golden pubescence. Pleura light 

 grey-brown, with patch of soft hairs near spiracle. Wings : 

 hyaline yeins brownish yellow, radius unforked. Abdomen 

 velvet-black, covered with golden pubescence; first segment 

 with fringe of long yellow hair, golden at base, pale at apex. 

 Legs : front legs, coxae very dark brown ; femora dark brown 

 at base, middle light yellow, brown at apex ; tibiae brown at 

 apex, middle yellow covered with light golden pubescence, 

 apex dark brown ; tarsi, all tarsal joints very dark brown, 

 last three almost black. Hind legs: coxse brown; femora 

 very yellow, witli golden pubescence, apex dark brown ; 

 tibiae, basal third yellow, apical two-thirds dark brown; 

 tarsi almost black, the second tarsal joint with excision near 

 base. Genitalia : basal pieces large ; claspers less than the 

 length of the basal pieces, blunt at apex, with single finger- 

 like process; the ends usually turned over mesally ; anal 

 plates, side-pieces very small and very constricted inwardly 

 at apices, bearing five to six stout bristles arising from very 

 distinct nodules, centre plate small and denude of bristles ; 

 adminiculum very broad, with a fringe of weak hairs along 

 the lower portion of pouch ; arms very chitinous, ending 

 mesially in two groups of strong black spines, the main spinal 

 process very serrated outwardly. 



Hab. Quick-flowing mountain-streams : obtained from 

 pupa attached to rocks. 



hoc. Bangan, Kamcrun, W. Africa, 14. 2. 1916. Altitude 

 2200 metres. 



Type in British Museum. 



Female. — Length 26-7 mm. 



Head: frons covered with silver pubescence ; face silver- 

 grey ; antennae dark brown with grey pubescence, first two 

 joints pale yellow, third joint pale yellow at base. Thorax 

 dull purple-black, covered with golden pubescence. Pleura 



