KEPORT ON THE PELAGIC HEMIPTEEA. 51 



the length of the body, rather slender ; first joint rather more than three-fourths of the 

 length of the other three together; second joint less than one-half the leno-th of the 

 first ; third one-fourth shorter than the second ; fourth nearly one-quarter longer than 

 the second, slightly attenuate from the middle upwards. 



Pronotum of usual shape with the usual anterior fovese, disk rather flat. Mcsonotum 

 widest behind the middle, disk convex. 



Front legs : femur rather stout, equally thick to beyond middle ; tibia about one- 

 fifth shorter than femur; tarsus (PI. I. fig. 6,f.t.), more than one-half length of tibia, first 

 joint rather more than half (nearly five-eighths) the length of the second, which is 

 cleft about the middle. 



Middle legs : trochanters and femora armed with short teeth ; femur rather shorter 

 than tibia and tarsus together; tibia about one-fifth longer than tarsus; tarsus (PI. I. 

 fig. 6, m.t.) second joint about one-fifth the length of the first joint. 



Hind legs (from the $ ) : trochanters and femora with fine teeth ; femur aljout two- 

 fifths longer than the tibia and tarsus together ; tibia four and a half or five times longer 

 than the tarsus ; tarsus cleft a little beyond the middle. 



Abdomen : sixth ventral segment a little longer than the fifth. 



Genitcd segments (PL I. fig. 6, g.) : first below nearly as long as all the ventral 

 abdominal segments together ; disk sloping forwards anteriorly, posteriorly flat, with an 

 oblique-sided hollow (from shrinking in dr5^ing ?), hind margin straight. Second below 

 with horns reaching four-fifths the length of the third below and with a tubercle near 

 the base of each. 



$ . Shortly ovate, widest behind the middle. Silvery ashy grey. Coxse, trochanters, 

 and base of femora below paler than in the male. Middle acetabula below more widely 

 and distinctly ochreous or nifo-ochreous, which colour sjireads to the adjoining part of the 

 hind margin of the mesosternum. First genital segment paler below. 



Head more convex. 



Pronotum more convex in middle, with two transverse fovese on each side, the anterior 

 larger and deeper. 



First genital segment below almost as long as all tlie ventral abdominal segments 

 together, tumidly convex in centre posteriorly, hind margin nari-owly straight in 

 middle, the sides somewhat obliquely rounded at the base. 



This species might readily be mistaken for sericeus, from which, however, it seems to 

 be structurally distinct. I have seen only three specimens (unfortunately not in the best 

 condition) from the following sources : — 



Celebes Sea, February 6 and 7, 1875, and between the Admiralty Islands and Japan, 

 March and April, 1875 (Challenger) ; "Mare della China" (Turin Museum). 



One specimen shows a curious abnormality of the right antenna (the left is broken), 



