On Aquatic Carnivorous Coleoptera or DytiscidcB. 801 



either side is a distinct, longitudinal, somewhat oblique fovea, extending from the middle to the line of 

 the base ; the surface is thicklj^ punctate ; when viewed obliquely, a transverse shallow depression may 

 be discerned near the middle, and also a minute punctured fovea near to the anterior margin ; in colour 

 black, the anterior margin and sides being distinctly suffused with flavous ; elytra broad, robust, very 

 finely pubescent ; beneath this pubescence are distinct punctures, and also a faintly punctate stria ; at 

 the anterior margin, halfway between the sutui-e and the lateral angles, is a short depressed fovea, corres- 

 ponding in position with the fovea on the thorax ; in colour a deep brown black ; abdomen and under- 

 side black : legs rufous : antennae rufo-fuscous." 



This is a species of Bidessus. — D. S. 



1397. Hydroporus masculinus. Crotch, Tr. Am. Ent. Soc. V, p. 74. North America. 



" Somewhat obovate, pointed behind, pale fulvous, breast and abdomen black ; head very finely puac- 

 tulate ; thorax short, transverse, sides straight, base margined with black ; finely and rather closely 

 punctulate ; elytra thickly and finely punctulate, pale yellowish, with the suture and four narrow lines 

 black (the fii-st and third not quite reaching the base). Mas, anterior claws much elongate, deformed, 

 subequal, the external one flattened. L. 4'75 m.m." 



"Lake Labache; very distinct by the male characters; the thii-d joint of the anterior tarsi is also 

 feebly bilobed and the claw joint is large and hardly longer than broad." 



This is a very distinct species of Ccelambus, and may be placed near Hydroporus nubilus (No. 403). 

 — D. S. 



1398. Hydroporus melancholichus, Motsch., Schrenck Reise, 18(50, p. 100. (Hydroporus lugubris, 

 Motsch., Bull. Mosc, 1845, IV, p. 353, pi. 6, f. 1). Kamtschatka. 



" Oblongo-ovatus, subdepressus, niger ; thorace transversim impresso ; hoc basi elytrisque dense 

 punctatis, ultimis parce pilosis ; antennarum basi, elytrorum margine reflecto pedibusque rufo-piceis. 

 Long. 1| Hgn., larg. 1 lign." 



" II ressemble un peu au H. planus, mais il est plus etroit. La tete est transversale avec deux 

 impressiones arrondies entre les yeux, et \ine troisieme moins profonde sur le front. Le corselet s'elargit 

 vers les elytres et presente vers la base une impression ponctu^e. Les 61ytreg sont un peu plus larges 

 que le corselet, en ovale allonge comme la base de ce dernier, la pubescence est peu epaisse ; la portion 

 reflechie des bords lateraux, la base des antennes et les pattes sont roussatres. Le dessous du corps est 

 noir." 



1399. Hydroporus mcestus. Walk., List. Col. Lord., p. 10. Waddy Ferran. 



" Black, elougate-oval, slightly shining. Head with a large reddish spot in the disc. Elytra smooth ; 

 each with three testaceous spots at the base, with two indistinct streaks in the disc near the base, with. 

 a testaceous costal streak proceeding from the base and ending in a patch at nearly one-thii-d of the 

 length, with an elongated testaceous dpt near the suture at half the length, with three posterior elongated 

 testaceous dots, one near the suture, two subcostal and near a testaceous costal line ; legs red. Length 

 of the body 2f lines." 



This name is in prior use for another species. I have not identified Walker's description with any 

 species known to me ; it is probably a Deronectes. — D. S. 



1400. Hydroporus monUicomis, Sahl., not. fenn., XIV, j). 154. Russian Lapland. 



" Breviter ovatus, depressus, nitidus, niger, palpis, antennis, pedibus apiceque elytrorum ferrugineis - 

 c.ipite basi rufo-piceo ; antennis medio iucrassatis, articidis subglobosis ; prothorace angulis posticis 

 acutiusculis elytrisque parce subtUissime punctatis, subglabris. Long. 1|^ lin." 



