TENEBRIONID^E 105 



Pe'ecyphorus Sol. 



Philolithus Lac. 



As originally organized by Solier this genus was a composite, no 

 two of his four species being assignable to any one genus, but, as 

 he figures the mouth-parts of mexicanus only, and as this is the 

 only one having the large scalene terminal joint of the maxillary 

 palpi a sexual character as previously stated, it is certainly 

 proper to assume mexicanus as the type of Pelecyphorus. It seems 

 probable furthermore, judging by the description, that mexicanus 

 is a species allied somewhat to the cegrotus morbillosus type and that 

 in a broad sense, therefore, Philolithus of Lacordaire must be con- 

 sidered a synonym. In the genus Pelecyphorus the general outline 

 of the body is quite different from that of Glyptasida, in having 

 the anterior parts much smaller when compared with the hind body 

 and in the truncate to broadly lobed form of the thoracic base, the 

 hind angles never being posteriorly produced as they are in that 

 genus, although occasionally posteriorly oblique as in <zgrotus. 

 The elytra have the two discal costae of Glyptasida, but the inner 

 one is very much reduced in prominence and is frequently obsoles- 

 cent; the ligula and palpi are also nearly as in Glyptasida. The 

 prosternum between the coxae is longitudinally impressed along 

 the median line; it slopes posteriorly much more gradually than in 

 Glyptasida, its truncate apex being more prolonged over the apical 

 margin of the mesosternum, this form of the prosternum constituting 

 a constant and very important difference between the two genera. 

 The outer apical angle of the anterior tibiae varies somewhat; in 

 some species, such as carinatus, the type of Philolithus, there is 

 hardly any eversion; but in others, such as cegrotus and actuosus, 

 the acute angle becomes rather prominent occasionally, though never 

 very strongly so as it is in Euschides for example; the tibiae are rather 

 more cylindrical than in some other genera. 



The species and subspecies of this, one of the more characteristic 

 of the American genera of the tribe, are numerous and those within 

 our faunal limits may be assigned to three very distinctly separated 

 groups as follows: 



with a dense crust of argillaceous material, from which the American species are 

 generally almost free, indicating some differences in habit; for "adobe mud" is as 

 all- pervading in New Mexico as it is in Durango. The prothorax is very broad, convex 

 and has two small oblique smooth areas. 



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