848 



Apparently approaches very near to C. Pennsylvanicus, 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 punctures of the stria?, altho' less 

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

 places. 



GENUS DIC^ELUS. 



D. *Leonardii. Keddish black, polished ; body, beneath, feet, and palpi 

 piceous; antennae 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 antenna} pi'ceous glabrous, remaining 

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

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

 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 with a small foveolus, each side of 

 the dorsal line, and having a fortuitous appearance. Elytra! strife impunc- 

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

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



The filiform antenna? will prevent this insect from being mistaken for Abax 

 coracinus, 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 fi,ev. L. W. 

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

 other species of the genus are found in this vicinity, namely, D. dilatatus, 

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



[New England Fanner, Vol. VII, No. xx, p. 150, Dec. 5, 1828.] 

 CONTRIBUTIONS TO ENTOMOLOGY. NO. V. 



Family Dytiscidce. 



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

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

 tory of all Avhich may be observed, whether inhabitants 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 



