29 



not during the night. It will follow its unfortunate victim several 

 miles back from the river and renders out-door work impossible." 



In March, 1907, the life-history and habits of Simulium damnosum 

 were studied at Abu Hamed by Mr. Harold H. King, Economic 

 Entomologist to the Wellcome Research Laboratories, Gordon 

 Memorial College, Khartoum, who, after describing the bionomics 

 of the Nimitti (S. griseicollis, Becker),* writes as followsf : " A 

 second and larger species of sandfly Simulium damnosum occurs 

 in the Sudan, in the vicinity of Abu Hamed, where it bears the name 

 of Kilteb. 



" The larva (fig. 5) resembles in shape and general appearance the 

 Nimitti larva, but can be distinguished from it by its relatively 

 larger size and darker colour. A dark pigmented patch is usually 

 present on either side of the first thoracic segment. 



" Length about 6 mm. 



" The pupa (fig. 7) is enclosed in a pocket-shaped cocoon, about 

 4 mm. in length, similar to that of the Nimitti pupa. The 

 respiratory appendages consist each of a double comb of tubes 

 which do not project much above the edge of the cocoon. 



" Life-history and habits. The life-history of the Kilteb appears 

 to be identical with that of the Nimitti. It has nevertheless been 

 recorded from only one locality in the Sudan viz.. the neighbour- 

 hood of Abu Hamed, where its larvae and pupae exist in the river in 

 company with those of the Nimitti. 



" The adult females are exceedingly vicious blood-suckers, 

 attacking chiefly the ankles and legs. Like the Nimitti, they are 

 most active during the hours of sunset and sunrise. 



' The Kilteb do not swarm around the face, trying to crawl into 

 the eyes and ears, but each fly, in a business-like way, settles on the 

 spot it has selected, takes a short preliminary tour, patting the 

 surface with its fore legs, and then, plunging its proboscis into the 

 skin, commences to feed. In from two to three minutes it is fully 



* See below, pp. 32-34. 



t Loc. cit., pp. 208-209: Mr. King's observations are illustrated (Plate XXIII., 

 figs. 3, 5, 7) with coloured figures of perfect insect, larva, and pupa. 



