On Aquatic Carnivorous CoJeopterj or Di/(isciihe. 4G7 



knowledge of the sexes of each, so that the tarsi may be compared, is essential 

 before a trustworthy conclusion can be arriv^ed at. 



North America, (Canada). 373. 



585. Hydroporus perplcxus, n. sp. — Ovalis, sat convexus, tenuiter pubescens, 

 niger, vix nitidus, pedibus fusco-rufis, antennis fusco-nigris, basi rufescente ; pro- 

 thorace limbo minus fortiter, disco sparsim subtlliter punctato; el3'tris sat crebre 

 et subtiliter punctatis; coxis posterioribus sat crebre et fortiter punctatis; abdomine, 

 basi excepto, minus crebre fere obsolete punctato. Long. 4^, lat. 2l m.m. 



The two specimens I have seen appear to be males, they have the front tarsi 

 moderately strongly dilated, with the claws simple. 



North America, (California). 372. 



586. Hydroporus rusticus, n. sp. — Oblongo-ovalis, evidenter pubescens, nigricans, 

 supra vix dilutior, pedibus rufo-fuscis, antennis fuscis basi minus \vete rufo ; pro- 

 thorace limbo minus fortiter, disco omnino sparsim subtiliter, punctato ; elytris sat 

 crebre et subtiliter punctatis ; coxis posterioribus crubre fortiter punctatis ; 

 abdomine (basi excepto) minus crebre subobsolete punctato. Long. 4, lat. 

 2f m.m. 



This species is very similar to Hydroporus tartaricus, Lee, (H. nigellus, Mann.) 

 (No. 597) but is rather larger, and the disc of the thorax is not quite so destitute 

 of punctures. 



North America, (Nevada). 371. 



587. Hydroporus tenebrosus, Lee, M.C. — Ovalis, minus convexus, evidenter 

 pubescens, subtus nigricans supra fusco-niger, pedibus rufescentibus, antennis fuscis 

 basi rufo ; prothorace limbo sat fortiter, disco subtiliter punctato ; coxis posterioribus 

 fortiter punctatis ; abdomine (basi excepto) minus crebre subobsolete punctato. 

 Long. 4f, lat. 2i m.m. 



Mas, supra sat nitidus, subtiliter sed evidenter punctatus, tarsis anterioribus 

 et intermediis bene dilatatis, illis unguiculis muticis. 



Fern., opaca obsoletius punctata. 



This species has the hind coxte more coarsely, but the ventral segments less dis- 

 tinctly, punctured than in the preceding species. 



The specimen sent me by Dr. Leconte is rather larger and of paler colour than 

 the other individuals I have described. H. sub-pubescens is perhaps also this species; 



TRANS. ROT. DCB. SOC, N.S., VOL. II. 3 P 



