332 A Preliminary Monograi^h of the 



senting antennal differences corresponding with those of the 

 preceding species, but less marked. It resembles anthracinus 

 very strongly, but maybe distinguished by its more robust form, 

 relatively larger and more transverse prothorax widest in the 

 middle, by its smaller, less prominent eyes, shorter, more robust 

 male antennae, and several other minor characters. 



GrKOUP II. 



The extreme southwestern parts of our territory and northern 

 Mexico furnish nearly all the known representatives of this 

 small group; but one species amongst those accessible to me at 

 present extends as far to the eastward as the Texan sea-coast. 

 The species are easily differentiated and may be thus tabulated: — 



Legs pale. 

 Punctuation excessively dense, the punctures of the pronotum con- 

 tiguous and the lustre alutaceous. 

 Color dark ferruginous, the abdomen black. 

 Elytra slightly shorter than wide; together broadly, angularly 



emarginate at apex 5 dentlger 



Elytra quadrate, subtruncate behind; body more robust, 



6 mexicanus 



Color of body black throughout 7 texanus 



Punctuation more sparse, the punctures of the pronotum distinctly 

 separated in the middle; lustre shining. 

 More slender, the apical angles of the prothorax very acute and 

 prominent, the punctures of the pronotum scabrous and dull 

 only very narrowly near the lateral edges; elytra black. 

 Lateral angles of the prothorax very narrowly but distinctly 

 rounded. 

 Prothorax one-third wider than long and much narrower than 



the abdomen 8 arinatu§ 



Prothorax nearly one-half wider than long and almost as wide 



as the abdomen 9 gilse 



Lateral angles of the prothorax angulate, the angle not appre- 

 ciably rounded 10 prominens 



More robust, the apical angles of the prothorax decidedly less 

 prominent, the punctures of the disk large, contiguous, and 

 scabrous in a very wide area near the sides; black, elytra paler, 



rufescent 11 pacificn§ 



Legs piceous-black; body black, shining; punctures well separated, 



12 arizonse 



