650 On Aquatic Carnivorous Coleoptera or Dytiscidce. 



Group 1. 



1006. Dytiscus seminiger, deGeer, Hydaticus seininiger, M.C. — Ovalis, sat latus, 

 parum nitidiip, niger, subtus ^^'osterno anterius capiteque in medio testaceis, supra 

 capite thoraceque rutis, illo in vertice nigro rufo-bimaculato, hoc basi in medio 

 extensius nigricante, elytris margine laterali flavo ; antennis pedibusque anterioribus 

 rufis, tibiis intermediis piceis, pedibus posterioribus nigro-piceis, unguiculo interno 

 quam externo vix duplo longiore. Long. 13, lat. 71 m.m. 



In the male of the sj^^^cies, the fringing hairs of the front tarsi are rather short, 

 and the palettes differ little inter se in size, those at the base not being very large, 

 the claws ai'e rather stout, are abruptly curved at the base and are sinuate beneath ; 

 the middle tarsi are broadly dilated and the basal patch of dense rough seta? is 

 rather large. The female has some coarse impressions on the thorax near the sides, 

 and a few similar marks at the side of each wing-case near the front. 



The species seems to vary but little, the female often has the black colour on 

 the thorax more extensive than in the male, so that it occasionally nearly attains 

 the front margin, the yellow lateral stripe of the elytra is, too, generally more dis- 

 tinct in its terminal portion than it is in the male. 



Eui'ope. (Sweden ; Fiulancl, 61°, Sahlberg ; England ; France ; Germany : Alpes IMaiitimes, sec. Bedel). 

 1038. 



1007. Hydaticus modestus, n. sp. — Oblongo-ovalis, parum latus, subtus nigro- 

 piceus, capite prosternoque rufis, supra capite thoraceque rufis, illo in vertice nigro 

 rufo-bimaculato, hoc basi in medio nigro, elytris nigris margine laterali pvinctisque 

 transversis subbasalibus ilavis, antennis pedibusque quatuor anterioribus rufis, 

 pedibus posterioribus piceis, unguiculo interno quam externo hand duplo longiore. 

 Long. 14, lat. 7i m.m. 



The male has the front tarsi rather large, their claws are ratlier long, are sud- 

 denly bent at the base and are sinuate beneath ; the middle tarsi are broadly dilated, 

 and the basal patch of dense rough setse is very large and conspicuous. 



I have seen only a single individual of the species (a male in very bad condition) ; 

 it seems to be very closely allied to Dytiscus seminiger, and is extremely similar to it, 

 but is of narrower form, the black colour at the base of the thorax is definitely 

 limited and does not reach quite so far forward as the middle, and there are faint 

 indications of a transverse line of pale colour on the elytra near the base. The 

 apices of the elytra are slightly sinuate, and in the female sex this is no doubt more 

 conspicuous. In size and form it appears to be very similar to Hydaticus america- 

 nus (No. 1009), but seems to Le readily distinguished by the absence of yellow 

 longitudinal lines on the wing-cases. 



North America. 1037. 



