THE EARLY STAGES OF WEST AFRICAN MOSQUITOS. 



109 



Segment II. Nine setae may be seen on this segment in a dorsal view, of which 

 C and D are as defined above. Internal to C, near the posterior margin of the seg- 

 ment, is a small dendritic tuft (D. T.). The setae external to C are as follows : a 

 small single seta (B) a httle external and anterior to C, a tuft of moderate size (B") a 

 little external and anterior to B, and a small tuft (B') a Uttle external and posterior 

 to B". Laterally, or ventro-laterally, there are three setae : the most anterior (A') a 

 very long, stout seta ; rather posterior to A' a seta (A) similar to the Lateral setae on 

 the more posterior segments ; and posterior to A a very small seta (S) similar in 

 appearance to the Postero-lateral setae on the ventral aspect of the abdomen. 



Segment VII. A, B, B', B", C, and D as defined above. There is no small seta 

 internal to C, but a httle external to it there is a small seta similar to C on the other 

 segments ; this seta is referred to in the Table as C. In addition there is a small 

 tuft (A') close to and a httle posterior to A. 



Segment VIII. A and D as defined above. In addition there is a dehcate seta 

 (P) situated close to the external margin of the root of the paddle. At the distal end 

 of the midrib of the paddle there are two very small setae (P' and P") ; usually single, 

 but sometimes forked at their ends or even divided more deeply. 



Table III. 

 A Comparison of the Dorsal Abdominal Setae ofthe Pupae of C decens andC. invidiosus. 



Seg- 

 ment. 



Seta. 



C. decens. 



C. invidiosus. 



I. 



Dendritic tuft ; large and well- 









developed, strong primary branches 



8-12 



8-11 





Antero -internal ; short, rather stout 



1, end occasionally 

 forked. 



1 





Antero- external ; rather long and 









strong 



2-3, usually 2 



2 





Medio-internal ; small 



1, or a small tuft* 



1, or a small tuffc 





Medio -external ; small, but longer 



Tuft of about 2-5 



Similar tuft 





than the Medio-internal 



hairs. 







Postero-internal ; very long, strong 



1-2, usually 1 



1 





Postero -external ; rather long and 









slender 



2 



1-3 





Lateral ; small, delicate 



1, end sometimes 



1, end sometime! 







divided. 



divided. 



II. 



A 



rather long and slender. . 



2 



1-3 





A' 



very long, strong 



1-2 



1-2 





S 



very small and feebly chituiised 



1 



1 





B 



small, rather stout 



1 



1 





B' 



small tuft 



Small tuft of 2-5 hairs 



Similar small tuft 





B'' 



small tuft, but considerably 









larger than B', situated between 









B and B' and anterior to them 



Tuft of 4-6 hairs 



Tuft of 4-6 hairs 





C ; moderate length, reaching nearly 









half way across the third seg- 









ment 



2-3, usually 2 



2 





D.T. ; smaU dendritic tuft . . 



Small dendritic tuft 



SmaU dendritic tuft 





D ; minute 



1 



1 



III. 



A ; rather long and slender 



2-3 



2-4 





B ; rather long and strong . . 



2 



2 





B' ; small tuft between A and B" . . 



Small tuft, 1-7 hairs 



Small tuft, 1-4 hairs 





B'' ; tuft, considerably longer than B', 











situated between B and B' . . 



Tuft, 3-7 hairs 



Similar tuft 



*In the case of small tufts, the number of constituent hairs, when given, is only approxi- 

 mate as it was often impossible to determine with accuracy the degree of sub -division. 



