AMERICAN COMPONENTS OF THE TENTYRIIN^ 201 



smaller ligula entirely exposed, the labial palpi distinct ; tarsi and 

 scutellum variable; mandibles bifid at tip; body oblong, de- 

 pressed, very roughly and densely sculptured Nosodermini 



Eyes coarsely faceted, more rounded; antennas received in dorsal 

 cavities, short and stout, the last three joints free, dilated, form- 

 ing a very compact 3-jointed club; mentum, ligula, mandibles, 

 labial palpi and form and rough sculpture of the body nearly as 

 in Nosodermini; scutellum very minute; body much smaller in 

 size Usechini 



17 — Scutellum obsolete; body elongate, the elytra more or less 



inflated, costate ; mentum large, closely filling the buccal opening, 

 completely covering the maxillag but exposing the ligula in a 

 large apical sinuation ; eyes very widely divided and coarsely 

 faceted *Adelostomiiii 



Scutellum extremely minute; body slender, with oval, inflated, 

 costulate elytra; mentum moderate, subquadrate, not filling the 

 oral opening and not sinuate at tip ; eyes coarsely faceted, 

 narrowly divided Araeoschizini 



18 — Spurs of the anterior tibise minute or obsolete 19 



Spurs of the anterior tibiae longer and distinct 22 



19 — Antennae thick, subfiliform, moderate in length and perfoliate 



as in the two preceding tribes 20 



Antennae very small, slender and compact; anterior coxte separated; 

 body glabrous 3 1 



20 — Anterior cox£e separated as usual; body elongate, convex, 



glabrous, the scutellum visible and sometimes large, the elytra 

 not costulate; eyes coarsely faceted; mentum moderate, sub- 

 quadrate, not filling the oral opening or covering the maxilljE. 



* Stenosini 



Anterior coxae contiguous; body slender, depressed, glabrous, the 

 scutellum very minute, rounded, the elytra not costulate, the 

 pronotum and front of the head remarkably excavated; eyes 

 coarsely faceted, wholly dorsal though on the deep sides of the 

 head; mentum transversely lunate, completely filling the semi- 

 circular oral cavity, covering the maxillae, the apex sinuate and 

 exposing the ligula .. Dacoderini 



21 — Antennae enlarged distal ly, received in a deep cephalic groove 

 continued into the propleurae ; mentum moderate, slightly trans- 

 verse, concave, covering the ligula and to a slight extent, the 

 maxillaj, the sides of the oral opening acute and prominent; 

 maxillary palpi small and slender, the last joint very narrowly 

 oval, obtusely pointed ; eyes wholly dorsal and far from the 

 margin of the head, extremely minute ; body narrow, elongate, 

 subparallel, convex, the scutellum small but distinct, triangular; 

 pronotum depressed at base Typhlusechini 



Antennae not enlarged distally, very compact, cylindric, free; 

 mentum moderate, subquadrate, wholly exposing the maxillae ; 

 Proc. Wash. A.cad. Sci., August. 1907. 



