44- BULLETIN 18 2, UNITED STATES NATIONAL MUSEUM 



riorly; alate; posterior coxae contiguous, "transverse" (in the usage 

 of previous writers, but "not expanded laterally and caudally" in 

 the usage of Blackwelder, 1936, p. 76) ; abdomen margined; sternites 

 of first and second segments not present. 



Remarks. — With the exception of P. capncornis Laporte all the 

 West Indian species belong to the subgenus Piestiis (s. str.), which 

 is characterized by its unarmed head, smooth pronotal disk, and stri- 

 ate elytra. P. capncornis belongs to the subgenus Ziropho-us Dal- 

 man, characterized by the two horns on the front of the head. It is 

 doubtfully West Indian. Another species of Piestus is recorded by 

 Leng and Mutchler (1914, p. 403) from Haiti; it is P. mexicanus 

 Castelnau. The type in the British Museum is very distinct from 

 all West Indian examples of the genus I have seen and leads me to 

 assume that the record is based on a misidentification. Specimens 

 of a PiestKS from Cuba, Haiti, and Trinidad in the British Museum 

 were identified by Dr. Cameron as P. niinutus Erichson. They dif- 

 fer, however, from Central and South American examples of rmnutus 

 in the same collection by the sculpture of the head and the puncta- 

 tion of the pronotum. They are herein assigned to P. penicillatus 

 (Dalman). 



I collected 268 examples of our species of this genus during 1935- 

 37; 62 examples were already in the collections of the United States 

 National Museum ; and 198 examples were studied in the collections 

 of the British Museum. In addition to these I have seen 25 examples 

 from the Museum of Comparative Zoology and 3 from the American 

 Museum of Natural History. 



KEY TO WEST INDIAN SPECIES OF PIESTUS 



1. Front of head prolonged as two horns 5. capricornis 



Front of head not prolonged 2 



2. Elytra with six striae 1. sulcatus 



Elytra with sixth stria obsolescent 3 



3. Snlci of pronotnm one-third length of pronotum or less 4 



Sulci about one-half length of pronotum 4. pygniaeus 



4. Pronotal sculpture very fine and sparse; large discal area 



smooth 3. penicillatus 



Pronotal sculpture comparatively coarse and very dense; only a 



small smooth area 2. fulvipes 



1. PIESTUS SULCATUS Gravenhorst 



Piestus sulcatus Gravenhorst, 1806, p. 224. — LkPelktier and Serviixe, 1825, 

 p. 123.— Erichson, 1840, p. 835.— Lacordairb. 1854, p. 128.— Sharp, 1876, p. 

 407. — Bernhauer and Schubert, 1910, p. 7. (Not Laporte, 1834.) 



Description. — Piceous to rufotestaceous. Head with supra-anten- 

 nal tumescences very feeble, united behind by a ridge feebly set off 



