On Aquatic Carnivorous Coleoptera or DytiscidcB. 703 



tinct species, the undersurface being of a pure yellow colour, and the yellow cinc- 

 ture of the upper surface being even broader than in that specis. 



Australia, (Darling River). 1120. 



T. 77.— Genus HOMCEODYIES. 



Coxal lines absent ; unguicular cleft broad and rounded at base. 

 This genus comprises three species* found in Australia and New Zealand. They 

 form two well-marked groups : — 



Prosternum distinctly cliaunelled along tlie middle, postero-external ) ^ llnO 

 angle of hiiid femur rectangular ; size small (15 ni.m.) long. J 



Prosteraum indistinctly grooved; postero-extei'nal angle of hind 1 -^j ,,„, , 110'' 

 femur acute or spinose ; size rather large (about 25 m.m. long). j ' 



1100. Dytiscus atratus, Fab., Tragus ntratus, M.C. — Minor, ovalis, anterius 

 conspicue angustatus, convexus, supra niger, capite anterius prothoraceque ad latera 

 testaceis ; el\ tris vitta marginal!, posterius attenuata et angustissima, testacea ; 

 subtus nigro-piceus, pedibus quatuor anterioribus testaceis, tarsis intermediis piceis, 

 pedibus posterioribus piceis, crassiusculis ; prosterno sulca angusta anterius dilatata 

 et profunda. Long. 15, lat. 9 m.m. 



In the male the front tarsi are small, their claws are moderately elongate, and 

 but little unequal, the palettes of the undersurface are small and oblong, the 

 pubescent area moderately large ; on the intermediate tarsi the three basal joints 

 are densely clothed beneath with rather long sexual pubescence, their claws are 

 simple and equal. 



This little species has a good deal of resemblance to Cybister senegalensis (No. 

 1145), but is readily distinguished from it by the sulcate prosternum. The few 

 specimens I have seen of the species show little variation, in some of them the 

 uppersurface has a faint metallic lustre. 



Australia, (Brisbane, Rockhampton, Clarence River, South Australia). 1115. 



1101. Cybister scutellaris. Germ., Tj-o^'ms scuieZ^am, M.C. — Ovalis, parum con- 

 vexus, supra olivaceus, capite anterius prothoraceque ad latera testaceis, elytris 

 vitta marginali posterius parum arguta testacea ; subtus testaceus ; pedibus pos- 

 terioribus piceo-testaceis, femoribus angulo posteriori-externo acute subspinoso ; 

 prosterno late obsoletissime sulcato. Long. 26, lat. 14 m.m. 



* The two folloMdug species should very probably be added to this number: — Cybister goryi, Aubd 

 (No. 1277 huj. op.) near No. 1100; Australia.— Cybister insularis, Hope (No. 1278), near 1100; 

 Tasmania. 



