MALE GENITALIA 69 
sometimes it is very elongate. The surface of the tergites and sternites bears 
many scattered hairs and these vary in coarseness and abundance with the 
species ; there is a series of coarser and longer hairs along their posterior margins. 
These marginal hairs, and still more so the others, are much less conspicuous in 
the Sabethini; in this tribe, however, the eighth segment bears numerous stiff 
bristles posteriorly, particularly beneath. 
THE ABDOMEN OF THE MALE. 
The abdomen of the male is often much longer than that of the female. The 
ninth and tenth segments are crowded together and carry the genital armature. 
Often the abdomen is depressed and of nearly uniform width throughout. The 
tergite of the first segment, as in the female, bears many long hairs. The abdo- 
Fig. 4.—Diagram of the male genitalia of Aédes: A, Side 
piece; B, Clasp filament; 0, Lobes of side piece; D, Harpe; 
#, Harbago; F, Unci. 
men is often strongly ciliate along the sides, numerous long hairs being inserted 
laterally on the tergites. This is true of Anopheles, Megarhinus and most 
species of Culex and Aédes as well as of many others. In other forms there is no 
obvious lateral ciliation but there is a tendency to increased coarseness of all 
the setee towards the tip of the abdomen. Sometimes the eighth segment is 
armed with many coarse setw. Usually the sete of the sternites are coarser in 
the male than in the female. In the Culicini there is a reduction in the size of 
the segments near the tip of the abdomen. In many Sabethini the abdomen is 
distinctly expanded towards the tip, and the sternite of the eighth segment par- 
ticularly, bears many coarse bristles. The male genitalia are very important 
in classification and for systematic purposes may be described as follows: 
The Male Genitalia (fig. 4)—The male genitalia consist of two thick 
conical appendages, the side-pieces (a). These each bear a smaller terminal 
