On Aquatic Carnivorous Coleoptera or Dytiscide. 427 
The male has the front and middle tarsi broader than in the female. and the 
claws of the front ones rather more developed, and its thorax is slightly broader 
and a little more curved at the sides. 
Southern Europe, Algeria, and the Canary Islands. (Andalusia, Blidah). 246. 
470. Deronectes amurensis, n. sp.—Oblongo-ovalis, omnium brevissime sub- 
tilissimeque (vix visibiliter) pubescens, subopacus, rufo-testaceus, subtus nigricans ; 
thorace anterius et posterius elytrisque lineis plurimis confluentibus subinterruptis 
nigris; elytris apicem versus denticulo minus conspicuo ; corpore dense subtilissime 
punctulato. Long. 42, lat. 22 m.m. 
In the male the front and middle tarsi are broad, and the unguiculi of the front 
pair are moderately elongate and slightly thickened, and the interior (or anterior) 
one is furnished near the base with an obtuse swelling or tooth. 
I have seen only a single male of this species, which has the hind angles of the 
thorax much less rounded than in the corresponding sex of Dytiscus depressus, (No. 
472); the black lines more completely cover the elytra, and the undersurface is 
black. Its larger size and broader form readily enough distinguish it from varieties 
of Dytiscus assimilis, (No. 471), with dark undersurface. 
Siberia, (Irkutsk). 242. 
471. Dytiscus assimilis, Payk., Hydroporus assimilis, M.C.—Oblongo-ovalis, 
convexiusculus, subtilissime brevissimeque pubescens, fere opacvs, testaceus, 
prothorace basi (sed vix antice) elytrisque lineis haud imterruptis nigris, corpore 
subtus vel ferrugineo vel infuscato; elytris apicem versus denticulo acuto; 
prothorace basi quam apice evidenter latiore ; corpore dense subtilissime punctulato, 
Long. 43, lat. 25 m.m. 
The front tarsi are broad in both sexes, in the male slightly broader and distinctly 
longer than in the female, and with the claws elongate and comparatively stout, 
and the interior one dilated towards the base ; the middle tarsi are broader in this 
sex than in the female. 
Europe; East Siberia. (Scotland, Alsatia, Nimes, Munich, Gastein), 245. 
472. Dytiscus depressus, Fab., Hydroporus depressus, M.C.—Obiongo-ovalis, 
brevissime subtilissimeque pubescens, subopacus, testaceus, thorace anterius et 
posterius nigricante, elytris lineis plus minusve confluentibus nigris, maculis 
pallidis interruptis ornatis; thorace lateribus rotundatis angulis posterioribus 
per-obtusis (4), vel rotundatis 9; elytris apicem versus denticulo acuto; corpore 
subtilissime punctulato, subtus suturis plus minusve nigro-ornatis. Long. 42, lat. 
22 mem. 
TRANS: ROY. DUB. SOC., N.S-, VOL. II. 
