On Aquatic Carnivorous Coleoptera or Dytiscide. 595 
the male tarsi are less dilated, and the fine aciculations or scratches on the elytra 
of the female are even less conspicuous, so that they can be scarcely said to be 
present. 
South America, (Cayenne). 625. 
895. Colymbetes sulcipennis, Cast., M.C.—Ovalis, subdepressus, niger, prothorace 
ad angulum antericrem, antennis pedibusque anterioribus rufis, posterioribus nigro- 
piceis ; prothorace crebre profundeque strigoso ; elytris singulo striis undecim basi 
perprofundis, ad apicem fere continuatis, aliaque ad marginem exteriorem anterius 
abbreviata. Long. 9, lat. 4¢ m.m. 
The male of this species has the three basal joints of the front and middle tarsi 
greatly dilated ; and the interstices of the elytra quite smooth ; in the female the 
interstices, except the three or four sutural ones, bear extremely fine scratches or 
aciculations, these however are confined to the basal portion. 
South America, Cayenne. 624. 
Group 14. (No. 896). 
Elytra with a submarginal stria, and twelve other striz on each. 
In this interesting species the striation of the elytra attains its maximum ; the 
strie are very regular and equidistant and deep, except that at the apex there are 
some detached fragments, which strongly suggest that this species has arrived at 
its perfect striation by a development from a condition similar to that still existing 
in No. 847 (C. interruptus). 
896. Copelatus aubei (Montr. forte), M.C.—Ovalis, sat depressus, niger, capite 
prothoracisque lateribus piceo-testaceis, antennis pedibusque rufescentibus; capite 
transversim in medio prothoraceque strigulis brevibus profundis; elytris striis 
duodecim per-profundis, vix ad apicem disintegratis, aliaque marginali anterius 
abbreviata. Long. 52, lat. 2? m.m. 
This species is very distinct by the coarse sculpture of the upper surface. The 
male is not easy to distinguish from the female, there being no differences of 
sculpture, and the front and middle tarsi are only obscurely incrassate (not 
dilated). Montrouzier’s description can scarcely be cited as the authority for the 
name of this insect. , 
New Caledonia. 679. 
TRANS. ROY, DUB, SOC,, N S., VOL. I, 4H 
