192 MEMOIRS ox THE COLEOPTERA 



regard to elytral sculpture: "striis geminatis utrinque tribus, 

 interstitio lato subsuturali plerumque laevi," the significant word 

 being italicized. I am unable to define latifovea, which also belongs 

 to this subgenus, not having seen authentic examples, but the 

 species described above under the name Icevicollis, is probably a 

 fairly typical representative; it differs from gyas, besides form and 

 sculpture, in having the hind tarsi shorter and much more slender. 



Group II. 

 Subgenus Ligyrus in sp. 



This subgenus is widely diffused but apparently does not occur 

 in South America, being replaced there by Group IV, as defined 

 above, which group, however, also extends to the northward into 

 Central America. The species are numerous, and when viewed in 

 series do not seem to be especially closely allied among themselves; 

 but they display rather few structural differences in special organs 

 or parts and are therefore difficult to classify in such manner as to 

 be recognizable very readily from description; I have therefore 

 adopted a geographic division as a primary character as follows: 



Species of the Atlantic regions 2 



Species of the Sonoran regions; body short in build and inflated behind 



to greater or less degree 13 



2 Basal joint of the hind tarsi large and triangular 3 



Basal joint slender basally, more abruptly enlarged apically ; body shorter 



in form, almost always inflated behind 4 



3 Form elongate-oval, convex, not posteriorly inflated, polished, black, 

 the elytra and sides of the pronotum somewhat picescent, the under 

 surface and legs blackish-piceous; head rather more than two-fifths 

 as wide as the prothorax, finely rugose, the clypeus more coarsely 

 and feebly, the base smooth; front longitudinally impressed along 

 the middle, the transverse ridge entire, not quite attaining the sides-; 

 clypeal teeth small, sharp and approximate; prothorax barely 

 one-half wider than long, the sides from above converging and nearly 

 straight almost to apical third, then more convergent and nearly 

 straight to the apex; basal angles narrowly rounded; punctures fine, 

 rather deep, everywhere very sparse; concavity smooth, the tubercle 

 rather strong; apical coriaceous margin well produced medially; 

 scutellum much wider than long, smooth, ogival ; elytra fully a fourth 

 longer than wide, not evidently wider than the prothorax, circularly 

 rounded in about apical two-fifths; punctures rather coarse and 

 impressed, notably sparse throughout and rather widely spaced 

 even in the geminate series, few in number on the subsutural interval, 

 each enclosing a small annulus as usual; punctures smaller and 



