232 CALIFORNIA ACADEMY OF SCIENCES. 



States, which may also be considered as Medon until future 

 investigation can be made with more ample material. These 

 three groups will then probably give rise to four allied 

 genera, or perhaps more properly, subgenera. 



LiTHOCHAKis Lacord. — Represented in our fauna by och- 

 racea Grav. , alutacea Cas., and giiadricolUs Csls. The last 

 tw^o differ from the first in sexual characters — although they 

 have the characteristic comb-like sculpture at the apex of 

 the fifth segment — and in the smaller, more acute and prom- 

 inent labral tooth. 



Metaxyodonta Cas.=LiTHOCHAKis Lacord. 



LiPAROCEPHALUS Mann. — No description of the anterior 

 tarsi is given, and the position of the genus is assumed. 



Aderochaeis Sharp. — Represented by A. corticina Grav., 

 and possibly also by iahacina Cas. 



EcHiASTER Er. — No species of this genus has yet occurred 

 within the United States, and it is therefore omitted from 

 the table. 



SciocHARis Arrib. — Although Dr. Sharp intimates that this 

 genus may occur within our limits, I have not yet seen it. 

 It may be easily recognized by the very robust first and 

 second joints of the antennse. The labrum is bidentate 

 and the integuments are generall}^ very finely and densely 

 punctate. 



APOCELLUS Ericbs. 



A. niger n- sp. — Moderately robust, convex; upper snrfcice intense black 

 throughout, except the elytral suture which is dark piceo-te.staceons; metas- 

 teruum, abdomen and head beneath black; prosternum and side-pieces paler, 

 piceo-testaceons; antennae same toward base, black toward tip; legs pale 

 luteo-testaceous, femora shaded piceous in the outer half; pubescence ex- 

 tremely sparse; integuments highly polished. Head distinctly longer than 

 wide; sides behind the eyes distinctly convergent and rather strongly arcuate; 

 base truncate and very feebly iucurvate in the middle; augles very broadly 

 rounded, coarctate with the sides; eyes small, in the middle, rather promi- 

 nent; on a transverse line slightly less than their own length behind them, 



