On Aquatic Carnivorous Coleoptera or Dytiscidce. 591 



comparatively small space along the middle smooth ; this smooth space reaches 

 however completely to the base : the strite of the elytra are rather fine, the sutural 

 one is rather distant from the suture and becomes very fine in its basal portion and 

 indeed altosfether obliterated near the base: between the ninth and tenth strice 

 may be seen the rudiments of another stria. I have seen only the tj^pe specimen 

 from Chevrolat's collection, which is a mutilated female; but I have received from 

 Herr Wehncke two individuals which may probably be the males of C. distinctus ; 

 the scratches on the thorax are absent but its surface is finely and sparinglypunctured; 

 the striae of the elytra are not so fine, and the size is rather larger ; they have the 

 front and middle tarsi moderately dilated, and the front tibiae nearly simple. 



Mexico, (Coll. Brussels Mus.;. G32. 



883. Copelatus c«latipennis, Aube, M.C. — Ovalis, subdepressus, angustulus, 

 nltidus, fuscescens, capite, thoracis lateribus elytrorumque basi, antennis pedibusque 

 rufis ; prothorace strigis minutissimis subtilissimisque ; elytris striis sat profundis ad 

 apicem fere continuatis, marginalique minus abbreviata; corpore subtus rufescente, 

 abdomine obscuriore. Long. 4i, lat. 2\ m.m. 



The male has the front and middle tarsi dilated, but not broad, and the front 

 tibiae are bent at the base, and have a notch below the knee : the female differs 

 only in the structure of the legs, the sculpture being quite similar in the two sexes. 



Brazil, (Santa Ritn, Aug. Sepr., 1850, Salilberg ; Espirito Santo). 630. 



884. Copelatus buqueti, Aube, M.C. — Ovalis, subdepressus, piceo-niger, capite, 

 thoracis lateribus elytrorumque basi extremo (hoc minus distincte) rufescentibus, 

 antennis pedibusque rufis, tibiis tarsisque posterioribus piceis ; prothorace strigis 

 sat numerosis sed haud rudis, basi laevigato; elytris striis profundis, ad apicem fere 

 continuatis, marginal! anterius valde abbreviata. Long. 6, lat. ^\ m.m. 



This species is smaller than Copelatus sulcatus, (No. 886) and has the sculjjture 

 of the thorax less developed ; the striae of the elytra though deep and broad do not 

 form such distinct grooves, and the elytra are indistinctly reddish at the base. 

 The male has the front and ndddle tarsi but little dilated: and tlie female seems to 

 differ from it only by the simple tarsi. 



South America, (Cayenne ; Columbia). 629. 



885. Copelatus exaratus, n. sp. — Oblongo-ovalis, subdepressus, piceo-niger, 

 nitidus, capite thoraceque versus latera dilutioribus, antennis pedibusque rufis, tarsis 

 posterioribv;s piceis ; prothorace crebre profundeque strigoso ; elytris singulo striis 

 decern per-profundis, ad apicem fere contiuuatii*, aliaque ad marginem exteriorem 

 anterius valde abbreviata. Long. 62, lat. Zh m.m. 



