On Aquatic Carnivorous Coleopteia or DijtiscidcB. 62^ 



only by the male tarsi, but by the small development of the vermiculate sculpture 

 of the prothorax, and by the wider spaces separating the transverse striae of the 

 elytra. 



North America, (Western portion ; Cala. sec. Crotch). 912. 



96fi. Colyrabetes exaratus, Lee, Cymatopterus exaratus, M.C. — Ovalis, elongatus, 

 convexus, subtus niger, coxarum posticarum processubus rufescentibus, supra capite 

 nigro, anterius testaceo, medio rufo-bimaculato, thorace testaceo, vitta discoidali 

 nigra, elytris fuscis, margine laterali testaceo; pedibus testaceis, femoribus medio 

 fuscis, prothorace sequaiiter conspicue veruHculato, elytris strigis transversis pro- 

 fundis remotis. Long. 17, lat. 8^- m.m. 



The male has the elytra moderately shining, and the transverse striae of about 

 one depth throughout ; while in the female the elytra are very dull witli a large 

 apical portion shining, the transverse furrows on the dull portion are deeper and 

 coarser than on the shining portion, so that the spaces between them are less. 

 The male tarsi seem to be almost the same as in the preceding species. The species 

 is very similar to Dytiscus striatus (No. 972), but the male may be readily distin- 

 guished by the basal band of glandular pubescence on its tarsi, and the female by 

 its sculpture, the furrows being finer, and the apical shining portion more clearly 

 differentiated from the dull part. 



Western North America, (Nebraska, Kansas, Oregon, Dacotah, Hudson's Bay, sec. Crotcli). 913. 



967. Colymbetes groenlandicus, Aub^, Spec. p. 233. — Ovalis, angustulus, parum 

 convexus, nitidus, subtus niger, supra capite anterius rufo, posterius nigro rufo- 

 bimaculato, prothorace testaceo medio plaga nigro-fusca, elytris fuscis lateribus tes- 

 taceis, pedibus rufis, femoribus medio infuscatis ; prothorace parum vermiculato, 

 elytris sat profunde transversim strigosis, strigis parum approximatis. Long. 14^, 

 lat. 7 m.m. 



The male has the prothorax almost smooth, while in the female it bears fine 

 vermiculate scratches : the sculpture of the elytra is almost similar in the two 

 sexes. 



Gvpfinland. 914. 



968. Colymbetes sculptilis, Harr., Cymatopterus sculptilis,M.C. — Elongato-ovalis, 

 angustulus, sat convexus, subtus niger, supra capite anterius rufo, posteriu.s nigro, 

 ruto-bimaculato, prothorace testaceo, medio plaga nigra, elytris fuscis, lateribus 

 testaceis, pedibus rufis femoribus medio leviter infuscatis ; prothorace crebrius, 

 sequaliter, undulatim reticulato, lateribus versus angulos posteriores parum rotun- 

 datis ; elytris profunde transversim strigosis, strigis approximatis. Long. 16, lat. 

 8 m.m. 



TBANS. BOT. DUB. SOC, N.S., TOL. II. 4 If 



