KEPORT ON THE PELAGIC HEMIPTERA. 61 



The Abdomen of the Female. 



The abdomen of the female (PL II. fig. 4 ? ah. a., 4 ? ah. b., 5 ? ah. b.) is on the 

 whole similar to that of the male. 



The Genital Segments of the Male. 



The first segment above is similar to the sixth abdominal segment, but narrower and 

 longer ; like it it is provided with an erect connexivum. Below it is ring-like, but nearly 

 as long as all the ventral abdominal segments together ; the hind margin is concave. 



The second is, below, longer than the first, the hind margin concave, the sides prolonged 

 and sloping upwards and backwards to the upper surface, where they form a convex 

 oblong j)late (with hairy margins) nearly concealing the tliird above. 



The third below is a convex roundish plate ; above is a small conical tubercle like 

 the podical plates in Halobates, nearly concealed, and embraced by the third segment 

 below. There is therefore reason to believe that the third segment above and the third 

 below are not to be considered as the same segment. I have had no opportunity of 

 making dissections. 



The Genital Segments of the Female. 



Three segments are visible above, l)ut only one below. The first and second above 

 resemble the sixth abdominal above, but are somewhat shorter and narrower. The third 

 above is a conical tubercle. 



The only segment visible l)elow is triangularly convex, with the apex truncate, the 

 sides sloping upwards and embracing the sides of the three segments above, forming, as 

 it were, a continuation of the erect connexivum of the abdominal segments. 



The Legs. 

 The Front Legs. 



As in Halobates, these are very short in comparison with the others, and for the 

 greater part of their length lie well in advance of the body. 



The Acetabulum (PI. II. fig. 5, ac.) is very large, occupying the outer third on each 

 side of the prosternum, and extending from the front to the hind margin. Its opening is 

 circular, and looks backwards and downwards ; on the middle line in front is a suture or 

 slit reaching from the rim to the base, but not triangularly emarginate as in Halobates. 



The Coxa is nearly altogether immersed in the acetabulum, appearing merely as a ring 

 above the opening. 



