AMERICAN COMPONENTS OF THE TENTYRIIN^ 49I 



similarly somewhat shouldered, the ridges less elevated and the 

 series of squamiferous punctures, separating the series of coarse 

 punctures, rather more prominent, so that all the series of pale 

 close-set squamns are more nearly equal in elevation; punctures 

 of the series distinct to the apex, though becoming notably smaller 

 posteriorly ; abdomen less dull, rather coarsely, somewhat sparsely 

 punctate ; spicule beyond the middle of the under surface of the 

 anterior femora a little larger than that of the intermediate femora 

 as in ar?natiis. Length 3.9-4.1 mm.; width 1.18-1.25 mm. 

 Wyoming (Green River), — H. F. Wickham...duplicatus n. sp. 



Although the coarse punctures of the elytral series generally 

 become materially less coarse toward apex, due to the contrac- 

 tion of the elytra, arniatus is the only one in which they 

 become obsolete, or nearly so, for a long distance from the apex, 

 this being a very remarkable distinguishing character of that 

 species ; the punctures become unusually small, for a much 

 shorter distance from the apex however, in decifiens also. 

 Duplicatiis was confounded with annatus by Dr. Horn, though 

 they are strikingly different in many characters, but especially 

 in the relative degree of prominence of the elytral ridges and 

 in the nature of the punctuation posteriorly. In arvzatus the 

 squama of the intermediate lines appear to be less securely 

 attached than those of the principal ridges, and I have one 

 specimen in which they have become entirely removed, except 

 in a portion of one line, while those of the prominent ridges are 

 undisturbed ; the tuberculiform punctures bearing them can 

 always be easily observed, however, so that this character can 

 be verified with a little care in observation. 



Tribe Dacoderini. 

 While widely removed from any other, this tribe betrays an 

 affinity with the Araaoschizini, and particularly the Adelo- 

 stomini, in the antennae, which are similarly stout, cylindric and 

 perfoliate, differing from the first only in having the eleventh 

 joint still more deeply sunken within the tip of the tenth, though 

 perfectly visible from an oblique anterior view, thus proving 

 that the antennee are really ii-jointed and not lo-jointed as 

 generally stated. In the Adelostomini the eleventh joint has 

 sunken still deeper within the capacious apex of the tenth joint, 

 in such manner as to have entirely disappeared, leaving only its 



