AMERICAN PHILOSOPHICAL SOCIETY. 471 



marginal groove dilated, piceous, re<embling a narrow deprc.s.^ed 

 margin and reflected edge, dorsal line distinct, lateral c-.1l'«-* nut 

 excurved near the hind angles, base wider than the petiole, pos- 

 terior angles prominent and rounded; elytra, striae punctured, in- 

 terstitial lines convex, third one with a puncture behind the 

 middle, aud one near the tip; feet piceous ; postpectu.'? punctured 

 each side behind the intermediate feet and at base; venter im- 

 panctured. 



This species very much resembles decentU, but the thorax is 

 more dilated, and the elytra narrower. It may be distinguished 

 by having the postpectus punctured both at base and each side. 



[Afterwards described by Germar as Piecilus monedula. — Lec.J 



18. F. I M PUNCTATA. — Black, glabrous, impunctured ; antennx 

 and palpi pale rufou.* ; fest testaceous. 



Length a little more than two-fifths of an inch. 



Bod}- black, impunctured, glabrous; [46] antennae slender, 

 extending beyond the humerus, and with the palpi pale rufous ; 

 thorax broadest rather before the middle, contracted behind, 

 margin a little depres-sed behind, the edge somewhat recurved, 

 posterior angles obtusely rounded, base impunctured; elytra pro- 

 foundly striated, striaa impunctured, interstitial lines convex, the 

 third one with two distant punctures ; feet testaceous. 



Resembles suhmarginatus and decentU, but is entirely destitute 

 of punctures ; the form of the thorax also is perfectly distinct. 

 I caught it on Mr. R. Haines's farm in Germantown. 



[Belongs to Pristodacti/Ia ; described by Dejean as P. ameri- 

 cana. — Lec] 



19. F. VENTRALis. — Black. glabrous, all beneath piceous- 

 black ; thorax at base not wider than the pedicel of the post- 

 pectus. 



Length rather more than two-fifths of an inch. 



Body above black, polished, beneath piceous-black ; antennx 

 piceous, with ferruginous hairs towards the tip ; labrum deep 

 piceous; palpi piceous; thorax before the middle as broad as the 

 elytra, gradually much contracted behind, base hardly wider 

 than the pedicel, lateral margin not depressed, edge not excurved 

 behind, dorsal line slightly impressed, basal lines distinct, con- 

 1823.] 



