MR. HALDEMAN'S DESCRIPTIONS OF COLEOPTERA. 101 



PLATYDEMA Lap. 4- BrulU, (1831). Ann. Sc. Nat. xxiii. 350. 



P. ELLiPTiCA F. (Mycetophagus) ii. 566. No. 3. Lap. Br., 380. No. 36. Black, 

 opaque, elytra each with an oblique sanguineous spot. 3 1. long. Rare in 

 Pennsylvania, abundant in the South. 



P. FLAVipES F. (Mycetophagus) ii. 567, No. 11. Lap. Br., 338. 



P. RUFiVENTRis Lap. Br., 378, No. 33. Pennsylvania and Georgia. 



P. BASALis Hald. Subdepressed, black, opake ; head impressed immediately in 

 front of the eyes, coarsely and densely punctate ; mouth flavous ; palpi, feet, and base 

 of the antennae rufous : prothorax emarginate in front, with the base bisinuate, finely 

 punctured, an indistinct fovea upon each side near the base : scatel finely punctured : 

 elytra with strongly impressed punctured striae : under parts rufo-piceous, strongly 

 and coarsely punctured, 2 1. long. Inhabits from New York to Georgia, in fungi. 

 More elongate than the preceding, with deeper elytral striae ; the head more coarsely 

 punctured than the thorax ; and the antennae are not ferruginous. 



P. ANALis Hald. Oval, shining black, head distinctly and confluently punctured ; 

 irregularly impressed from the eyes converging forwards and meeting along the 

 clypeus, a transverse obsolete impression posteriorly : antennae . . . base, mouth and 

 feet flavous; prothorax finely punctate, base on each side impressed, lateral margin 

 slightly reflexed, extreme margin faintly rufous : elytra punctate-striate, interstices 

 flat, iuflexed margins rufo-piceous : beneath rufo-piceous, coarsely punctured, 

 abdominal segments with'a fovea upon each side, two apical ones black. 2 1. long. 

 Distinguished from P. basalts by being glossy, and in wanting impressed striae upon 

 the elytra. 



P. L^viPEs Hald. Oval, shining black, head depressed, thickly punctate ; an 

 impressed transverse line in front of the eyes : prothorax very minutely punctured, 

 moderately emarginate before and bisinuate posteriorly ; a fovea upon each side of the 

 base, and a corresponding obsolete one anteriorly ; lateral margins reflexed, 

 converging rectilinear ly from the posterior angles to beyond the middle ; basal angles 

 acute, anterior ones obtusely rounded : scutel small : elytra strongly striate, striae 

 punctured, interstices flat, impunctured : antennae rufous, labrum and palpi 

 ferruginous: beneath piceous, strongly punctate : feet shining rufo-piceous. 2i 1. 

 long, 1 1. wide. Allied to P. basalts and P. analis, but distinguished from the former 

 by the gloss and pale antennae ; and from the latter by the smoother pronotum and 

 more deeply impressed striae. Inhabits the Middle States. 



P. L^vis Hald. Oval, shining black, smooth: head with a fine transverse 

 impressed line between the eyes; labrum and clypeus rufo-piceous; antennae, mouth. 



