232 BULLETIN 18 2, UNITED STATES NATIONAL MUSEUM 



Medonella Casey is not at all similar to Thinochnris, but some of 

 the South American species of Thinocharis will probably require new 

 subgenera. All our species belong to the subgenera Sciocharis and 

 Sciocharella, which differ from Thinocharis (s. str.) in having the 

 labrum bidentate. Sciocharis has the gular sutures most approxi- 

 mate along the middle or posteriorly, whereas Sciocharella has them 

 most approximate anteriorly. 



I have examined 182 specimens of this genus from the West Indies, 

 including the types of all but one of the valid species. Of these 130 

 are in the British Museum, 2 are in the Casey collection and 2 in the 

 general collection of the United States National Museum, and 40 were 

 collected by me in 1935-37. These belong to six species, of which two 

 appear to be new. 



KEY TO WEST INDIAN SPECIES OF THINOCHARIS 



1. Gular sutures most approximate anteriorly " 2 



Gular sutures most approximate posterioi'ly or along middle " 3 



2. Punctures of head moderate and distinct 5. smithi 



Punctures of head minute and very dense 6. exilis 



3. Labrum with a median denticle and two laterals; seventh sternite of male 



not modified 1. poundi 



Labrum without median denticle ; seventh sternite of male modified 4 



4. Labrum with very short minute denticles; emargiuation of seventh sternite 



in male not bounded laterally in any way 2. bakeri 



Labrum with distinctly triangular and prominent denticles ; emargination of 

 seventh sternite in male bounded laterally by denticles 5 



5. Elytra with' discrete tuberculi ; emargination of seventh sternite in male 



bounded laterally by a minute denticle 3. chapini 



Elytra without discrete tuberculi ; emargination of seventh sternite in male 

 bounded laterally by a strong tooth 4. fuscina 



1. THINOCHARIS POUNDI, new species 



Description. — Eufopiceous, elytra testaceous with large sutural in- 

 fuscation, abdomen rufotestaceous. Head nearly one-fourth wider 

 than long; eyes large, at much less than their diameter from base; 

 sides behind eyes nearly parallel, base feebly arcuate but angles mod- 

 erately prominent; base slightly emarginate at middle; neck nearly 

 one-half as wide as head; gular sutures moderately separated along 

 middle, feebly diverging at both ends; without distinct punctures 

 but with dense and rather uneven sculpture ; with very fine pubescence 

 and the usual longer hairs; labrum with two small acute denticles and 

 a smaller one between them. Pronotum one-sixth wider than long, 

 seven-eighths as wide as head; widest at anterior angles, moderately 

 narrowed posteriorly, angles all rounded; with a rather indefinite 



" The West Indian species cnn be separated also on tlie sculpture of the pronotum. In 

 Bcioclinrrlla (2) the surface is finely or coarsely punctate; in Sciocharis (3) it is tuborcu- 

 late but not at all punctate. 



