558 On .iqinU/'c Carnlrorous Coleoplcra or DytiscldiE. 



796. Ilybius obtusus, n. sp. — Ovalis, haud angustus, subdopressus, fere opacus, 

 niger, supra nigro-subteneus, antennis crassiusculis rufis, articulo ultimo apice fusco, 

 pedibus piceis; prothorace margine lateral! lato ; elytris deusius minus subtiliter 

 reticulatis, et versus apicem fere punctatis, puuctis subseriatis magnis ; coxis 

 posterioribus subobsolete reticulatis, margine anteriore minus cur%'ato; prosterni 

 processu minus elongate. Long. 9f, lat. 5 m.ni. 



The female has a plica or fold in the middle of the apex of the last ventral 

 segment, which does not project backwards at all. 



I have seen only a single individual of this species, which seems to be a very 

 distinct one, only likely to be confounded with I. senescens, and Dytiscus angustior 

 (Nos. 790 and 791), which ii resembles in size, and its little elongate prosternal 

 process; but the nmch more conspicuous scul{)ture of the elytra will make the 

 determination of this species very easy. 



Eastern Siberia. S.'JO. 



797. Dytiscus biguttulus, Germ., Ins, sp. nov. p. 29. — Ovalis, fere brevis, 

 convexus, subtus piceus, supra nigro-seneus, limbo anterius minus ferrugineo, 

 elytrorum epipleuris ferrugineo-seneis, antennis pedibusque anterioribus rufis, 

 pedibus posterioribus piceis ; supra sub-opacus, elytris densius subtiliusque 

 reticulatis, guttulis duabus pallidis, quarum posteriore conspicua ; cuxis posteriori- 

 bus subtiliter strigosulis et punctatis, margine anteriore extus alinipte curvato ; 

 jjrosterni processu elongate. Long. 9\, lat. oj m.m. 



The male has the basal joints of the front and middle tarsi a little incrassate, and 

 furnished beneath with moderately long hairs which bear small palettes ; the claws 

 of the front feet are not elongate, the anterior one is very slightly, the hinder 

 rather deeply, emarginate near the base ; on the hind feet the outer claw is 

 acuminate, and differs only slightly from the inner, except in its length ; the ajjical 

 ventral segment, has a rather short carina along the middle of its apical portion, 

 and its hind margin is only obscurely rugose from a slight elongation of the 

 punctures wliich it bears ; the female has the apex of the last segment, with a short 

 plica, and a rather broad short apical emargination, and is smooth at the sides, 



This species is shorter in form than any of the three preceding; and is 

 smaller than L subasneus No. (789), and has the front border of the hind coxte 

 more abruptly defle.xed at its outer part. It greatly resembles I. oblitus (Nc. 801), 

 but is distinguished by the less approximation of the front border of the hind coxce 

 to the middle coxal cavity. 



North America. 843. 



798. Ilybius similis, Th., M.C — Ovalis, convexus, niger, subtus nigro-piceus, 

 antennis pedibusque quatuor anterioribus rufis, pedibus posterioribus rufo-plceis, 



