On Aquatic Carnivorous Colcoptera or Di/tiscid(e. 481 



Mas, sat nitidus, tarsis anterioribus et intermediis fortiter dilatatis, illis ungui- 

 culis insequalibus, anteriore crassiore, ultra medium subdentato, apice tenui. 



Fern., opaca, tarsis articulo tertio elongato. 



This species varies a good deal in colour, and especially in the extent of the 

 marks on the elytra. 



Northern Europe, and Siberia, (Sweden; Finland to 68" 10' North, Sahlberg; Britain, France, 

 Germany). 342. 



Group 6. 



631. Hydroporus kraatzii, Schaum, M.C. — Ovalis, convexus, breviter tenuius 

 pubescens, subopacus, niger, antennis pedibusque lufis ; capita latissimo ; prothorace 

 disco convexiusculo, crebre punctato ; elytris crebre obsolete punctatis ; coxis 

 posterioribus sat fortiter punctatis ; tibiis tarsisque anterioribus latis. Long. 3, 

 lat. ll m.m. 



This species is readily distinguished from H. celatus, by the broader head and 

 more obsoletely punctured elytra ; I am unable to see any sexual characters. 



Europe, (Germany). 391. 



632. Hydroporus celatus, Cik., M.C. — OvaHs, hand elongatus, breviter tenuius 

 pubescens, subnilidus vel fere opacus, niger, antennis pedibusque rulis ; capite 

 magQO ; prothorace disco subtiliter punctato, elytris crebre minus fortiter punctatis, 

 punctis apicem versus obsoletis ; coxis posterioribus fortiter punctatis ; tibiis tar- 

 sisque anterioribus latis. Long. 3l, lat. ll m.m. 



This is a variable species ; in Britain some of the specimens are duller and more 

 distinctly punctured than others, and in some the elytra are rufescent towards the 

 extremity, and there is also a good deal of difference in size ; all the specimens 

 have the legs and antennae clear red. The Piedmont specimens are smaller and 

 more shining, and have the thorax rather less punctured, and the antennse some- 

 what infuscate, but I do not think they are thus distinguished in a definite manner. 

 The few specimens I have seen from the Pyrenees, are even more polished than 

 the Piedmont variety. I do not see any sexual characters, the tarsi being broad in 

 all the specimens. 



Europe, (Britain ; Seine ; Pyrenees ; JIacugnaga). 390. 



633. Hydroporus nevadensis, n. sp. — Oblongo-ovalis, elongatus, tenuissime 

 pubescens, nitidus, niger, antennis pedibusque rufo-testaceis ; prothorace medio 

 impunctato ; elytris crebre distincte punctatis, punctis ad apicem obsoletis ; coxis 

 posterioribus fortiter punctatis. Long. 3^, lat. li m.m. 



