348 



Apparently approaches very near to C. Pennsijlvanicus, Melsheimer; but 

 differs from Mr. Say's description of that species in being pubescent, in the 

 paler color of the base of the antenna? and feet, and in the differently 

 colored elytra, and truncate labruni, the jiunctures of the stria?, altho' less 

 distinct, are by no means obsolete at tip. Found under stones in wet 

 places. 



GENUS DICELUS. 



D. *Leonard'd. Reddish black, polished; body, beneath, feet, and palpi 

 piceous ; antenn89 fawn-colored. 



Length half an inch. 



Body glabrous, polished, impunctured, above deep piceous or reddish 

 black, beneath paler. Mandibles and labrum black, palpi piceous at base, 

 paler at tip. Three basal joints of the antennae piceous glabrous, remaining 

 ones covered witli fawn-colored pubescence. Thorax quadrate, diameters 

 equal, not contracted before; anterior angles simply rounded; somevihat 

 contracted behind the middle, and rectangular at base, where it nearly 

 equals the coleoptra in breadth ; lateral edge not reflected ; dorsal and lat- 

 eral lines deep; anterior part of the disc witli a small foveolus, each side of 

 the dorsal line, and having a fortuitous appearance. Elytral stria? impunc- 

 tured; interstitial lines very convex, submarginal one serrato-punctate 

 within. Feet piceous, tarsi paler abcpve, and almost fawn-colored beneath. 



The filiform antenna? will prevent this insect fi'om being mistaken for Ahax 

 coracinux, Say, to which it appears to have some resemblance. The latter 

 insect is known to me only by description. 



This fine Diccelus was sent to me from Dublin, N. H. by the JJev. L. W. 

 Leonard, whose kindness I am happy to acknowledge by the name. Two 

 other species of the genus ai'e found in this vicinity, namely, D. dilatalus, 

 Say, and D. elongalus, Bonelli. They are found under stones, but are rare. 



[New England Farmer, Vol. VII, No. xx, p. 156, Dec. 5, 1828.] 

 CONTRIBUTIONS TO ENTOMOLOGY. NO. V. 



Family Dytiscidoe. 



In order to distinguish our friends from our enemies, insects decidedly 

 injurious from those that are beneficial to mankind, we nuist study the his- 

 tory of all which may be observed, whether inhabilants of the air, the earth, 

 or the water. The insects of this family pass the first and last stages of 

 their existence in lakes, ponds and pools. They are among those that make 



