402 On Aquatic Carnivorous Coleoptera or Dytiscide. 
gequaliter subtiliter punctatis, serie punctorum impressa minus distincta: coxis 
posterioribus externe minus crebre punctatis. Long. 5, lat 2? m.m. 
This species is readily distinguished from Hydroporus nubilus (No. 408), by its 
larger size, and more finely and densely punctured elytra. I have seen only two 
individuals, both of which are females, one is shining, the other dull; the front tarsi 
are less compressed and are broader than in the corresponding sex of Hydroporus 
nubilus. 
North America, (Nevada). 209. 
405. Hydroporus fraternus, Leec., M.C.—Ovalis, sine pubescentia, nitidus, 
ferrugineus, abdomine pectoreque nigris, elytris signaturis fuscis, fortiter crebre 
eequaliter punctatis, punctis apicem versus fere densis; coxis posterioribus, 
abdomineque ad basin punctis magnis profundis densis. Long. 33, lat. 22 mm. 
Mas, tarsis anterioribus fortiter, intermediis sat dilatatis, illis unguiculo interno 
paulo crassiore. 
I have seen only a single male of this species. 
North America, (California). 219. 
406. Hydroporus polonicus, Aubé, M.C.—Ovalis, fere sine pubescentia, sat nitidus, 
testaceus, abdomine pectoreque vel nigris vel testacies ; elytris creberrime subtiliter 
punctatis, punctis ad basin ineequalibus; prothorace elytris evidenter angustiore, 
lateribus leviter obliquis. Long. 43, lat. 2} m.m. 
Mas, tarsis anterioribus et intermediis valde dilatatis, anterioribus unguiculis 
crassis, clongatis, subrectis, externo paulo breviore ; abdomine coxisque posterioribus 
nigris. 
Frem., abdomine coxisque posterioribus testaceis. 
According to Aubé there is a female form of this species which is quite dull and 
more finely punctured. 
Europe, (Poland, Southern Russia). 220. 
407. Ceelambus sahlbergi, n. nom,.—d¢. Ovalis, fere sine pubescentia, sat nitidus, 
testaceus, abdomine pectoreque nigris ; elytris creberrime subtiliter punctatis, punctis 
ad basin ineequalibus, prothorace elytris evidenter angustiore, lateribus leviter 
obliquis ; coxis posterioribus parce sat fortiter punctatis. Long. 44, lat. vix 23mm. 
Mas, tarsis anterioribus et intermedius articulis 1 et 2 leviter dilatatis ; anterioribus 
unguiculis crassis, elongatis, subrectis, externo paulo breviore. 
I have seen but one individual which scarcely differs from the male of H: 
polonicus, except by the little dilated tarsi. 
