64 GEO. H. HORN, M. D. 



vex, a few scattered large punctures, smooth in front. Elytra oval, narrower at 

 base than the thorax, humeri prominently dentiform, striae rather fine, hut deep, 

 with very large, round distant jiunctures, intervals slightly convex, smooth. 

 Mesosternum coar.sely punctured, not carinate between the cox». Length .14 

 inch ; 3.5 mm. 



The above is virtually a copy of the original description. From 

 my memory of the type it is really impossible to say whether it 

 should be referred to this or the nevadensk group. In any event it 

 may be known by the large and distant punctures of the finer elytral 

 striae. 



Occurs at Detroit, Mich. ; a second specimen has been taken in 

 Maryland by Mr. Ulke. 



A. (Oxyomns) ca<laTeriiiiis Mann. — Oblongus, supra nigi-o, subtus rufo- 

 piceus, clypeo profuude emarginato. thorace anterius dilatato, varioloso, elytris 

 punctato-striatis. Longit. 3 lin. Lat. I'i lin. 



Habitat in California, Trogium instar in cadaveribus exsiccatis. 

 D. Eschscholiz. 



The above is the entire description, and there is nothing to guide 

 one as to its position except that the thorax is dilated in front and 

 variolose, pointing in a manner either to the nevadensls group or that 

 immediately preceding. 



OXYOMUS Cast. 



This genus was considered by Erichson a division of Aj)hodius, 

 and the same view was adopted by Lacordaire, although the latter 

 author remarks that the mouth parts make a passage toward Am- 

 moecius and Psaramodius. 



The only obvious character separating it from Aphodius is found 

 in the costate elytra. The costse are quite acutely elevated, while 

 the striae are replaced by broad grooves often so coarsely and closely 

 punctured that the bottom seems divided transversely by small par- 

 titions. 



The only species known to our fauna has been introduced. 



O. porcatus Fab. — Oblong, parallel, moderately convex, brownish piceous, 

 opaque. Antennse and palpi rufotestaceous. Head feebly convex, sparsely finely 

 punctate. Clypeus hemiliexagonal, the angles obtuse, sides feebly arcuate, gense 

 moderately prominent, obtuse. Thorax one-half wider than long, not narrowed 

 in front, anterior angles obtuse, sides scarcely arcuate, hind angles well defined, 

 but obtuse ; base arcuate, but slightly irregularly, the marginal line absent ; disc 

 convex, the median line broadly sulcate behind the middle, surface moderately 

 coarsely, but not closely punctured, the punctures finer in front. Elytra as wide 



