OF PHILADELPHIA. 235 



PSELAPHUS Herbst. Latr. 



1. P. OARiNATUS. — Reddish-brown; elytra rectilinearly trun- 

 cated ; tergum tricarinate, and witb an elevated edge ; anterior 

 tibia arcuated. 



Inhabits the United States. 



Body with short hairs : head deeply indented on the front ; 

 vertex with two small indentations : maxillary palpi with the 

 three last joints dilated; the ultimate one triangular or cordate, 

 being widely emarginate at tip ; the inner lobe somewhat mucro- 

 nate ; penultimate joint also large and triangular, with a slender 

 spine or seta as long as the joint placed on the exterior angle ; 

 antepenultimate joint rounded, with a spine on the exterior side, 

 similar and equal to that of the other joint : thorax rounded, 

 somewhat angulated on the middle of the side, punctured : elytra 

 not quite half the length of the abdomen ; minutely punctured, 

 with two obtuse, elevated lines on each, obsolete before the tip, 

 and with an impressed groove between them: tergum rather 

 darker than the elytra, carinated along the middle, and with an 

 abbreviated, carinate line each side at base ; edge elevated : an- 

 terior tibia somewhat arcuated, gibbous before in the middle. 



Length less than one-tenth of an inch. 



This species is not uncommon, and is often found under the 

 loose bark of the yellow pine ; it [98] is referrible to the genus 

 Ctenistes Reich. The elytra are terminated by a straight line 

 like those of the dresdensis. It seems probable that the cordate, 

 terminal joint of the maxillary palpi, and the two elongated 

 spines of the preceding joints, may be peculiar to one sex, as a 

 specimen in my collection has but a single spine, and the termi- 

 nal joint is acute and not dilated. 



[Belongs to Tmesiphorus. — Lec] 



2. P. RiPARius. — Reddish-brown ; elytra rectilinearly trunca- 

 ted, half the length of the tergum ; tergum simple ; anterior tibia 

 rectilinear. 



Inhabits Missouri. 



Vertex convex, with an impressed line each side : antennae, 

 joints from the third to the eighth, inclusive, subequal ; ninth a 

 1824.] 



