NORTH AMERICAN COLEOPTERA. 91 



The mouth parts are practically identical in Pleurophorus and 

 Psammodius, and the anterior femur is as stout or stouter than the 

 posterior. The middle and posterior tibiae of Pleurophorus are 

 slender, not thickened at tip, the spurs are slender as in Atienius, 

 but less elongate. The posterior tarsi are slender, not compressed, 

 the joints not triangular, the claws of normal size. 



All the species of Psammodius have the side of the thorax fim- 

 briate, but no such structure is seen in either of the Pleurophorus. 



In Psammodius there is a feeble trace of the carina of the second 

 venti'al segment, but in no species so well marked as in Pleurophorus. 



Two species are known to me : 



Clypeus veiTucose, thorax irregularly coarsely punctured, anterior fenuir cniar- 

 giuate beneath ctfSUS. 



Clypeus finely sparsely punctate, thorax very regularly, not densely punctured, 



anterior femur entire veutralis. 



P. csesus Pauz.^Form slender, elongate, piceous black, shining, subcyliu- 

 drical, legs ferruginous. Antennse pale rufotestaceous. Head moderately con- 

 vex, a few coarse punctures along the occiput, in front verrucose. Clypeus 

 broadly emarginate at middle, the angles obtuse, sides arcuate, gensc feebly 

 prominent, very obtuse. Thorax about one-fourth wider than long, slightly 

 broader in front, anterior angles obtuse, sides feebly arcuate, hind angles dis- 

 tinct, hut obtuse ; base arcuate, with distinct marginal line, disc moderately con- 

 vex, a deep postapical groove beginning at the front angles, but not reaching the 

 middle, a large round fovea at middle of declivity sometimes divided into two 

 smaller fovese, the median line impressed with coarse deep punctures, the surface 

 very coarsely and irregularly sparsely punctured, a smooth space at the sides. 

 Elytra a little narrower than the thorax, humeri obtuse not carinate ; sides i)ar- 

 allel, the stripe deep, punctate, intervals slightly convex, smooth, crenate on their 

 inner border. Mesosteruum opaque, rugulose, carinate between the coxae. 

 Metasternum smooth, deeply longitudiually impressed. Abdomen smooth, the 

 segments crenate in front, the second segment carinate at middle. Anterior 

 femur emarginate on its lower edge forming thereby two obtuse teeth. Posterior 

 femur smooth, the marginal line fine, but entire : the tibi£e slender, spurs slender 

 and long, tarsi long, the first joint nearly as long as the next three. Length .1-2 

 inch; .3 mm. 



This is one of the smallest Aphodiides in our fauna, very nearly 

 of the same general form as Ata'nins (/ntcili% but rather more convex. 

 The punctuation of the thorax is somewhat closer in some specimens, 

 these may possibly be females, at all events no sexual chai-nctcrs have 

 been observed otherwise. 



In this species the first three elytral strijv only are eiitiri' and nacli 

 the apex. 



Occurs abundantly in Europe, and probably intro<lu('ed in our 

 country, where it is foiuid in the Middle States regions ixud occasion- 

 ally abundantly near Baltimore (Lugger) and Washington (Vlke). 



