648 On Aquatic Carnivorous Coleoptera or Dytiscida. 



I. 67.— Genus PRODATICUS. 



Coxal lobes broad, their supra ai-ticular border rather narrow ; claws of hind feet 

 nearly equal in length. 



The only species is found in western Asia. (Persia and North India). 



1005. Prodaticus pictus, n. sp. — Sat latus, parum convexus, nitidus, niger, capite 

 anterius prothoraceque lateribus testaceis, vertice testaceo-bimaculato, elytris 

 maculis decern censpicuis flavis, antennis (parum elongatis) pedibusque anterioribus 

 rufis, pedibus posterioribus piceis : prothorace lateribus subrotundatis, angulis 

 posterioribus obtusis ; tarsorum posticorum unguiculis fere sequalibus ; elytrorum 

 punctis seriatis censpicuis. Long. 15, lat. 8| m.m. 



The male has the undersurface of the front tarsi irregularly covered with palettes 

 about thirty-six in number, there is no definite division of them into larger and 

 smaller, but those in the middle of the heel are much larger than the marginal 

 ones : the three basal joints of the intermediate tarsi are broad, and bear beneath 

 very numerous small palettes quite irregularly placed, but with a rather broad 

 uncovered line along the middle. The terminal two joints both on the front and 

 middle feet are less elongate and slender than in the allied forms. 



The yellow marks on the elytra are very conspicuous ; they consist on each of an 

 elongate mark on the shoulder, a very large basal spot near the scutellum, two 

 large spots beyond the middle placed transversely, the inner one rather remote 

 from the suture, and the outer quite separate from the hind margin, and a subapical 

 spot, touching neither the suture nor the outer margin. 



I have seen only two individuals of this remarkable species, which cannot 

 easily be confounded with any other ; the form of its thorax suggests a likeness to 

 Agabus. 



Northern India. 1000. 



I. 68.— Genus HYDAIICUS. 



Coxal lobes but little developed in the transverse direction, but with broad and 

 definite supra-articular border ; inner claw of hind tarsus tmce as long as the 

 outer. 



The species are very difficult to distinguish, I arrange them provisionally in 

 three groups viz : — 



