ROLAND HAYWARD. 61 



impressions rather small, bistriate ; sides with the margin very narrowly reflexed 

 feebly arcuate in front, nearly parallel behind ; hind angles I'ectangular, finely 

 carinate. Elytra scarcely one-half wider than the thorax, oblong-ovate, moder- 

 ately deeply striate; strife entire, punctate, the punctures becoming obsolete 

 towards the tip ; third stria with the first dorsal puncture slightly in front of the 

 middle, the second about one-fourth from apex; intervals slightly convex. Be- 

 neath black, shining. Legs black. Length .15-. 19 inch ; 3.75-4.75 mm. 



More elongate and depressed than concolor, from which it is abun- 

 dantly distinct by the proportionally longer thorax, which is as wide 

 at base as apex, with the hind angles rectangular. The elytra are 

 less deeply striate, with the stride more finely punctured, and the legs 

 are black. From quadralum and longulum it differs in having all 

 the elytral strise entire, the thorax proportionally less wide as com- 

 pared with its length, and from the latter, in addition, by the thorax 

 not narrower at base than apex. 



From a very careful study of Chaudoir's description I am con- 

 vinced that tetragonoderuM is synonymous with this species. 



It extends from the Rocky Mountain region westward to the 

 Pacific coast, occurring in Wyoming, Colorado, New Mexico, Ne- 

 vada, California and Washington. 



Group vii. planatum. 



Mouth-parts as in the last group. Frontal grooves single, straight, 

 parallel ; eyes large, prominent. Prothorax trapezoidal, scarcely 

 convex, truncate at base ; basal impressions bistriate, the outer stria 

 as long as, or longer than the inner ; hind angles distinctly carinate. 

 Elytra without paler markings, usually finely striate ; third stria 

 with two dorsal punctures ; humeri rounded ; eighth stria not dis- 

 tinct from the margin. Legs usually piceous or black, sometimes 

 rufo-piceous. 



In the above definition of the group no mention is made as to 

 whether the head is alutaceous or not. The reason for this is, that 

 in some species it is either shining or finely alutaceous, but I have 

 been unable to make use of this character in their separation. This 

 is rao.st noticeable in fuuereum, vueklini and their allies, and it is to 

 be noted that the head is most apt to be alutaceous in .specimens from 

 more Northern regions. 



This is one of the most difficult groups of the genus for study. 

 Many of the species resemble each other very closely, and it is by 

 no means improbable that some of them may have to be united when 

 more collecting shall have been done in Alaska and the extrenie 

 Northwest. A large number of those herein contained wei'e de- 



TRANS. AM. ENT. SOC. XXIV. FEBRUARY, 1897. 



