Goleopterological Notices, V. 499 



Texas. 



I have not seen the ant with which this species lives, and am 

 uncertain also of the sex of the unique individual. Sexual differ- 

 ences appear to be very feeble in this particular group of genera. 



AIVITRA Ti. gen. 



Body short, compact, moderately convex. Head triangular, the 

 antennal tubercle short, narrow, strangulated at the sides, not at 

 all divided by a median depression and continuous with the surface 

 behind it ; vertex with two very feeble subobsolete fovese separated 

 by nearly one-third the total width, and also another larger behind 

 the tubercle. Eyes large, nearly at the base, half divided by the 

 .posterior canthus; sides of the head behind them transversely ex- 

 cavated beneath ; sides between the eyes and the frontal constric- 

 tion long convergent and perfectly straight. Maxillary pa]|)i mode- 

 rate, slender, cylindrical, three-jointed, the first minute; second arcu- 

 ate, gradually increasing in thickness from base to apex; third 

 shorter, cylindrical, with an internal and external seta at apex. 

 Labial palpi slender, the terminal seta very long. Antennae long, 

 cylindrical, with an elongate terminal joint ; club long, very feeble, 

 three jointed. Prothorax sinuate at apex above, with a broad lon- 

 gitudinal discal depression from the apex to basal fourth, where 

 there is a pronounced obtusely elevated median tubercle before the 

 basal margin. Elytra ample, with a fine sutural, and partial discal, 

 stria, each coarsely bifoveate at base. Abdomen with the first four 

 dorsals subequal, strongly margined ; first ventral short but visible 

 from side to side ; stomata of last dorsal distinct at the lateral angles. 

 Prosternum deeply, broadly emarginate at apex, prominent later- 

 ally, very short before the coxae which are long and conical. Meso- 

 sternum short, smooth. Metasternum moderate. Intermediate 

 coxae very narrowly, the posterior rather widely, separated; inter- 

 mediate trochanters long, the insertion terminal; anterior and pos- 

 terior shorter. Legs rather slender ; second joint of the tarsi 

 shorter than the third ; ungues well developed, stout, subequal. 



This remarkable genus evidently belongs to the Ctenistini, but 

 exactly in which direction its affinities are most pronounced it is 

 difficult to state. In the recent table of the Ctenistini by Mr. Raff- 

 ray I should be disposed to place it in a distinct section between 

 Chennium and Ctenistes and the three principal headings would 

 then read : — 



