On Aquatic Carnivorous Coleoptera or DytiscidoB. 625 



The male has the upper surface shining, wliile in the female the elytra are very- 

 dull, with the apical parts shining ; the sculpture of the latter sex is scarcely so 

 deep as it is in the male. The male front and middle tarsi have the whole of the 

 three basal joints densely and uniformly clothed beneath with one kind of glandular 

 pubescence. 



Siberia. 907. 



961. Colymbetes paykulli, l£r., Cymatopterus paykulli, M.C. — Elongato-ovalis, 

 convexus, niger, antennarum basi testaceo, clypeo rufo, vertice parum conspicue 

 rufo-bimaculato, thorace lateribus fasciaque mediali parum discreta in medio late 

 interrujita rufis, elytris marginibus rufescentibus ; corpore strigoso, strigis trans- 

 versis elytrorum sat profundis. Long. 19, lat. 10 m.m. 



Each sex in this species has the elytra shining, and similarly sculptured : the 

 male tarsi are hardly so broad as in the preceding species, and the pubescence of 

 the basal portion of the tirst joint is of a distinctly different character to that 

 beyond it, this distinction is greater on the middle than it is on the front feet. 



Europe ; North America, (Sweden ; Finlajid 68° 30', Sahlberg; North Germany, western North America). 

 908. 



962. Colymbetes longulus, Lee, Cymatopterus longulus, M.C. — Elongato-ovalis, 

 angustulus, sat convexus, niger, antennarum basi testaceo, clypeo rufo, vertice rufo- 

 bimaculato, pro thorace lateribus testaceis, elytris fuscis, marginibus testaceis ; corpore 

 strigoso, prothorace disco profundius vermiculato, strigis transversis elytrorum sat 

 profundis. Long. 16|, lat. 8 m.m. 



I have seen only the male of this species, the front and middle tarsi are rather 

 narrow, and more compressed than in C jDaykulli ; the pubescence at the heel of 

 the basal joint of each is of a quite different character from the glandular pubes- 

 cence beyond it ; the emargination of the last ventral segment is slight. 



The sjDecies cannot be considered closely allied to C. paykulli, it is smaller, 

 narrower, and more parallel, less sombre in the colour of the upper surface ; with 

 the sculpture of the thorax of a different character, and the male tarsi different. 



North America, (Lake Superior, Kansas). 909. 



963. Colymbetes seminiger, Lee, Cymatopterus seminiger, M. C. — Ovalis, hand 

 angustulus, convexus, niger, antennarum basi testaceo, clypeo rufo, vertice rufo- 

 bimaculato, prothorace testaceo, pkiga transversa discoidali nigra, elytris fuscis 

 marginibus testaceis ; corpore strigoso, prothorace disco verniiculato, strigis trans- 

 versis elytrorum sat profundis. Long. IS, lat. 9| m.m. 



Of this species T have seen only the male ; it does not appear to me very closely 



