326 BULLETIN" 182, UNITED STATES NATIONAL MUSEUM 



opa&vm, S\inv\) = pAicry ptina opaca (Sharp) (monobasic and orio-inal 

 designation) ; of Gastrolohium,^ Lathrobiiwi hicolor Gravenhorst= 

 Ga-'ttrolohium hicolor (Gravenliorst) (designated by Blackwelder, 

 1939) ; oi II esperolyintn. Crypt ohivm tnmidum 'LcC()ntf = Hi^speroJjhtm 

 tmnidwn (LeConte) (original designation) ; of Homoeohium, Ilomo- 

 eotarms {Homoeohium) halcerinnmn Blackwelder (monobasic and 

 original designation) ; of NenweoUm^ Gr-yptohhan, nihigh^sum Bern- 

 hauev= II omocota9\ms (Nemoeofus) nibiginosus (Bernhaner) (mono- 

 basic and original designation). 



Diognosls. — Body very elongate, parallel; integuments moderately 

 densely punctate; antennae anteriorly flexile, strongly geniculate, 

 basal segment much elongate; labrum bilobed; fourth segment of 

 maxillary palpus subulate; gular sutures separate; neck more than 

 one-half as wide as head, abruptly constricted across dorsal surface; 

 prosternum not dilated under the coxae; hypomera feebly lobed 

 behind coxae; anterior coxal cavities open behind; front coxae large, 

 ex.serted; elytron with a longitudinal fold above side margin; middle 

 coxal cavities confluent; posterior coxae contiguous, "conical''; flrst 

 and second abdominal sternites absent; third longitudinally carinate 

 at base; fourth and fifth in male sometimes with a median fovea, fifth 

 sometimes lobed (males sometimes dimorphic) ; basal half of anterior 

 tibia with a concavity lined with diagonal ctenidia, with a corres})ond- 

 iiig prominence on the femur; apex of posterior tibia with a ctenidium 

 on each side. 



Remarhs. — This genus is distinguished by the structure of the an- 

 tennae and the presence of the pleural elytral fold. It is rather 

 variable in the secondary male characters, and the subgenus Gastrolo- 

 hiinn^ to which all our species belong, is highly developed in this 

 respect. At least some of the species have dimorphic males. 



The name given above to this genus has not previously been used 

 in connection with New World faunas (except temporarily by Casey, 

 1889a, p. 182). The division of the genus Cryptohlurn on the char- 

 acter of the elytral fold leaves us with four subgeneric names, of 

 which one must be the generic name as well. The oldest name is 

 n omoeotarsus and must be accepted on that basis. 



I have seen 187 specimens from the West Indies. Tlieso I assign to 

 4 species, of which 2 are new. 



KEY TO WEST INDIAN SPECIES OF HOMOEOTARSUS 



1. Head with ground sculpturo throughout 2 



Vertex between eyes witliout ground sculpture 1. solus 



2. Pronotum with dense ground sculpture 4. testaceipes 



Pronotura without ground sculpture 3 



3. I^'ovea of fifth sternite obsolescent, very shallow 3. obsolescens 



Fovea of fifth sternite distinct, deep, usually oval and srrongly concave. 



2. albipes 



