On Aquatic Carnivorous Coleoptera or Dytiscida. 267 



25. Noterus Ifevis, Sturm, M.C.— Ovalis, latiusculus, sat convexus, nitidus, 

 castaneus, antice dilutior ; elytris apicera versus punctis minutis ; prosterno medio 

 carinato ; femoribus posterioribus subtus apice macula densa pubescentige. Long. 4^, 

 lat. 2\ m.m. 



Mas, antennis breviusculis, irregularibus, articulo quinto maximo, quam sexto 

 valde transverso latiore et duplo lougiore, articulis 7 — 10 longitudine latioribus ; 

 corpore subtus femoribusque colore obscuriore ; tibiis posterioribus intus densissime 

 ciliatis. 



Fem., antennis fere regularibus, corpore subtus ferrugineo, fere concolore. 



Southern Euvojie, and Algeria. 524. 



II. 2. — Group SuPHisiNi. 



Swimming legs very feeble, rather widely separated at their articulation ; the 

 femora with elongate cilise at the extremity of their hind margin ; front coxse 

 placed very near the front edge of the prosternum, this latter thickened along the 

 middle longitudinally ; front tibia3 very twisted, with an extremely large terminal 

 hook. 



The group comprises only two genera ; they are remarkably globose insects, 

 although distinctly acuminate behind. 



Prosternum forming a prominent angle in front of anterior ) ^„r zjT-T-rc / -j i i % 

 coxse. A single North American species. / ^ ^^^^ ^^^ (''*«« below.) 



Prosternum flexed in a gradual curve in front of anterior ( r-Trnrjrc/ -i 



coxEe. South American and West Indian species. ]'^'^^ ^'^^^ (''■^''^ P- 26»-) 



I. 7.— Genus COLPIUS. 



Middle of the prosternum so prominent in front that it forms a conspicuous 

 outstanding rectangle ; epipleurre abruptly inflexed, horizontal through their whole 

 length. 



The unique species is North American. 



26. Colpius inflatus, Leconte, M.C. — Convexus, ovalis, postering sat acuminatus, 

 sine pubescentia, opacus, niger, antennis pedibusque rufis, supra sanguineo- 

 maculatus, subtus capite thoracisque lateribus rufescentibus ; elytris fortiter 

 punctatis ; corpore subtus opaco, coxis punctis paucis magnis, abdomine impunctato, 

 margine apicali setoso. Long. Si, lat. 2i m.m. 



United States, (Louisiana, Florida, fide Crotch). 463. 



TRANS. BOT. DUE. SOC, N.S. VOL. n. 2 N 



