On Aquatic Carnivorous Colcojjtcra or DytiscidcB. 349 



infascato; elytris nigro-fuscis, fascia lata interruptasub-basali,maculaque magna ante- 

 apicali testaceis ; elytris cum thorace dense, distincte, fere oequaliter punctatis ; coxis 

 posterioribus crebre fortiter punctatis ; clypeo anterius marginato. Long. 2, 

 lat. li m.m. 



North America. 138. 



257. Hydroporus plicipennis, Crotch, Tr. Am. Ent. Soc. IV, p. 388. — Oblongo- 

 ovalis, sat latus, fere opacus, brevissime pubescens, fuscus, thorace testaceo, basi et 

 margine anteriore fuscis ; elytris fliscia lata, interrupta, sub-basali, et macula magna 

 ante-apicali testaceis, cum thorace asqualiter dense et distincte punctatis, sutura 

 sat elevata, disco plica longitudinali, lata, elevata ; antennis jjedibusque obscure 

 rufis ; pectore rufo, dense fortiter punctate ; clypeo anterius marginato. Long. 2, 

 lat. It m.m. 



The only specimen I have seen is a male, and has the front and middle tarsi 

 rather strongly dilated. 



California. 139. 



258. Hydroporus flavicollis, Lee, M.C. — Oblongo-ovalis, opacus, brevissime evi- 

 denter pubescens, testaceus, elytris fuscis, fasciis latis duabus interruptis testaceis ; 

 elytris cum thorace densissime subtiliter punctatis, coxis posterioribus crebre fortiter 

 punctatis. Long. 1#, lat. 1 m.m. 



The outline of this peculiar little species is much that of Dytiscus duo- 

 decempustulatus, (No. 4G2) ; in the male the front and middle tarsi are distinctly 

 dilated : the hind tibite seem to approximate to those of Deronectes and Hydroporus ; 

 in the only individual I have been able to examine the wings are abortive, so that 

 this will probably prove to be a very distinct and important species. The hind tibiae 

 seem to make a link between Bidessus and Deronectes ; in the specimen I broke 

 up, the wings as stated were undeveloped. 



North America, (Illinois, Pennsylvania, Massachusetts). 141. 



259. Bidessus obesus, n. sp. — Latus, ovalis, convexus, brevissime pubescens, fere 

 opacus, obscure testaceus, elytris obsolete fusco-signatis, thorace et elytris dense 

 subtiliter, fequaliter punctatis ; coxis posterioribus dense fortiter punctatis ; clypeo 

 minus distincte marginato. . Long. 2, lat. 1| m.m. 



This species is similar in appearance to Hydroporus cribrosus, Schaum, (No. 242), 

 but the upper surface is much more densely, finely, and evenly punctured. The 

 male has the front and middle tarsi distinctly dilated. 



North America, (Texas). 142. ■ 



