THE PUPAE OF WEST AFRICAN MOSQUITOS. 7 ( .> 



3. Stout branched seta at the posterior angle of the 6th segment, 



fringe shorter . . . . . . . . . . . . . . S. metallica. 



No such special seta on the 6th segment ; fringe longer ; midrib 

 more highly chitinised . . . . . . . . . . S. luteocephahi. 



4. Paddles narrow ; single seta or a poorly developed tuft on the 



8th segment . . . . . . . . . • . . . . S. unilineata. 



Paddles broader ; tuft on the 8th segment well developed 5 



5. Long fringe on the paddles . . . . . . . . . . S. africana. 



Short fringe on the paddles . . . . . . . . . . . . . . 6 



6. Paddles with distinct notch . . . . . . . . . . S. simpsoni. 



Paddles without distinct notch . . . . . . . . . . . . . . 7 



7. Single seta on the 7th segment ; tuft on the 8th of subplumose 



hairs . . . . . . . . . . . . . . . . S. apicoargentea. 



A single or usually a double seta on the 7th segment ; tuft on 

 the 8th with only one or two hairs subplumose . . . . S. fasciata. 



The tufts and setae of Stegomyia are variable both in different individuals and on 

 the two sides of the same pupa, so that it is necessary to examine more than a single 

 specimen in those cases where these structures are used in differentiating the species. 



We have not had an opportunity of examining the pupae of S. sugens, S. africana, 

 and S. apicoargentea but have relied on the descriptions by Wesche for the differ- 

 ential points. 



Stegomyia luteocephala, Newst. 



The paddles are oval and rather narrow, but not so narrow as those of 

 S. unilineata, they have a long fringe and a highly chitinised midrib, and the 

 terminal seta is well developed. There are tufts at the posterior angles of the 

 7th and 8th segments, those of the 8th segment being the larger. These tufts 

 vary in size considerably, and those on the 7th segment may be reduced to 

 stout bifid hairs in some specimens, but as a rule they are well developed on one 

 or other side of the body. On the 8th segment there is a single simple hair internal 

 to the tuft, but the segment is otherwise almost bare. All the other segments carry 

 a number of small setae, especially at their posterior margins, which are mostly 

 simple, although a few are bifid ; none of these hairs is conspicuously or strongly 

 developed. The dendritic tufts on the first segment are not very strongly developed 

 and have only a small number (about 7) of primary branches. 



Stegomyia metallica, Edw. (fig. 3). 



The paddles are oval, with a short fringe, a well-developed midrib, and a long 

 terminal seta. At the posterior angles of the 7th and 8th segments there are setae 

 differentiated as tufts of subplumose hairs ; those on the 8th segment being small 

 but definite tufts, those on the 7th being little more than strong double or triple 

 branched hairs. The 8th segment is bare but for the tuft at each angle and a small 

 simple hair internal to it. On the 7th segment there are, in addition to the tufts, 

 a number of simple hairs, mostly situated on the posterior margin, and a pair of 



