AMERICAN COMPONENTS OF THE TENTYRIINyE 375 



vals with a sinjj;le uneven series of rather smaller, more widely 

 spaced punctures ; abdomen Hnely but distinctly, not very sparsely 

 punctured medially. Length 6.3-7.0 mm.; width 2.4-2.S5 mm. 

 Texas (near El Paso) pallidum Csy. 



As tending to show the propriety of associating the genera 

 from Triinylis to Chilomctofon^ to form a natural tribe, it may 

 be noted that the anterior angles of the prothorax bear vibrisste, 

 particularly long and conspicuous in Chilomctopon and Promc- 

 topion, but shorter and less evident in Triniytis, though so dis- 

 tinct in Trimytis obovata as to have been especially mentioned 

 by Mr. Champion, and, as further tending to show the intimate 

 relationship of the Trimytini and Eurymetoponini, attention may 

 be drawn not only to the similarity of general habitus, but to the 

 singular short longitudinal impression on the lower part of the 

 elytral flanks before the middle, so prevalent in both tribes, 

 becoming obsolete only in Trimytis and a few subapterous 

 Eurymetoponids, and evidently correlated in some obscure way 

 with the winged condition, in common with the transverse ante- 

 coxal grooves. It is interesting, in view of his subsequent 

 change of opinion, that Dr. Horn should have associated 

 abnorme originally with Trimytis, and in fact described it as a 

 species of that genus. He afterwards very properly founded 

 for it a special genus, but for some very inadequate reasons 

 referred it to the Epitragini, where it is wholly out of place, as 

 shown by the structure of the mentum, as well as by its general 

 habitus. His first impulse in this case was the correct one. 



If the language used in describing the punctuation of the head 

 in abnorme is at all correct, it differs a good deal from the next 

 three species of the table, but, in any event, as the species are 

 known to be moderately numerous and are unquestionably all 

 very local in habitat, there can be but slight risk of synonymy 

 in the above interpretation of the species ; the description of 

 abnorme is drawn from the original diagnosis. The enormously 

 elongated terminal joint of the antennee in ensifer, which is 

 founded upon a unique male, raises the question of sexual differ- 

 ences. Pallidum is the only species in which both sexes are 

 represented before me, and here the sexual differences in gen- 

 eral form of the body and particularly in the development of the 



