612 On Aquatic Carnivorous Coleoptera or DytiscidcB. 



The male has the front and middle tarsi a little incrassate and compressed, and 

 furnished beneath with moderately small palettes, the front claws are moderately 

 long and slender, and nearly equal, the front one being nearly straight, the hind 

 one scarcely longer, but more bisinuate ; the middle claws are short, and of about 

 equal lengths, the outer one being remarkably thick. 



I have seen but a single male individual of this species, it seems allied to 

 Colymbetes vicinus, but to be rather longer and less convex, to have the claws on 

 the hind tarsi shorter and thicker, and the claws on the front and middle feet 

 different : a female in Wehncke's collection, probably belonging to this species, has 

 the posterior tarsi shorter ; in other respects it resembles the male, the thorax not 

 being in the least constricted in front. 



1 obtained this species in the collection of W. W. Saunders, Esq. Although 

 labelled Peru, I think it may possibly be from Mexico : Wehncke's female is labelled 

 " ChiU? " 



South America, (Pei-u). 878. 



930. Colymbetes divisus, A.uh6, Rhantua dirisus, M.C. — Ovalis, elongatus, hand 

 convexus, sat nitidus, subtus niger, supra testaceus, vertice nigro rufoque variegato, 

 thorace in disco maculis duabus parvulis fuscis, elytris creberrime nigro-irroratis, 

 minus subtiliter reticulatis, antennis fusco-testaceis, basi testaceo, pedibus rulis, 

 posterioribus magis obscuris ; prosterno in medio minus elevate ; pedibus posteriori- 

 bus gracilibus, articulo 4o gracili, unguiculo externo parvo quam interne triplo 

 breviore. Long, loi, lat. 5i m.m. 



The male has the front and middle tarsi considerably incrassate and moderately 

 compressed, and furnished beneath with rather large palettes, the claws of the front 

 feet are moderately long and stout, and are somewhat thickened and bisinuate 

 beneath, the front one being a little longer, and less sinuate than the other ; the 

 middle claws are of Yevj unequal length, the outer one being about twice as long 

 as the greatly curved inner one. The species is known to me only from the type 

 out of Dejean's collection ; it is remarkable from the fact that the coxal processes are 

 deeply divided, and the coxal lines less turned outwards, so that the form of the 

 coxal processes is more slender in the transverse direction, than it is in the allied 

 species ; this character is a slight approximation to Lancetes. 



North America, (Norfolk Sound). 879. 



931. Rhantus longipos, n. sp. — Ovalis, elongatus, baud convexus, sat nitidus^ 

 subtus niger, prosterno anterius cum processu testaceo, supra testaceus, vertice 

 rufo nigroque variegato, thorace in disco maculis duabus parvulis fuscis, elytria 

 creberrime nigro-irroratis, antennis iusco-testaceis basi testaceo ; pedibus rufis 



