6 GEO. H. HORN, M. D. 



i=e)H(i?e.— Autcrior tibial spur slender aud acute at tip. Upper middle tibial 

 spur longer than half the lower. First joint of hind tarsus slender, rarely as 

 long, never longer than the next three together. 



This species varies in the color of the elytra, usually they are pi- 

 ceous, but may vary to brown, while many fi-om Utah and Oregon 

 have the base, suture and side margin nuich palei-. 



In many specimens, es])ecially females, the elytra are apparently 

 truncate at apex, allowing the pygidium to be exposed, but this is so 

 variable in appearance, as has been observed in erraticns, that no part 

 can be drawn from it. 



Occurs from Maine to Oregon, in the region north and a little 

 south of the great lakes and in the mountain region extending south 

 to New Mexico and northward to Hudson's Bay. 



Subgen. Colobopterus Mnls. 



Scutellum elongate, one-fifth the length of the suture. Anterior 

 tibiae tridentate, not serrulate above, the anterior face smooth, the 

 tarsus with the first joint shorter than the second. Posterior tibiae 

 fimbriate at tip with unequal spinules. Front tuberculate at middle 

 in the male. 



One species represents this group in our fauna. 



A. erraticus Linn. — Subdepressed, black, elytra greyish yellow with the 

 suture darker. Head rather densely punctate, the clypeus feebly eniarginate, 

 the gense rounded, not prominent; antennse x>iceons. Thorax moderately closely 

 punctate, the hind angles obtuse, the base sinuate in front of the humeri, basal 

 marginal line entire. Elytra scarcely longer than wide conjointly, striate, strijE 

 finely punctured, intervals very slightly convex, finely alutaceous, finely not 

 densely punctate, apex subtruncate. Body beneath sparsely punctate at middle, 

 more coarsely at the sides. Posterior femora sparsely punctate; first joint of 

 hind tarsus as long as the three following. Length .30 inch ; 7.5 mm. 



The only sexual distinction observed is the small, but very evident 

 tubercle of the front of the male, the head of the female being en- 

 tirely plain. 



This species has been introduced from Europe, doubtless through 

 commerce, into the Middle States. Many years ago Melsheimer de- 

 scribed a specimen under the name pensvallensis, but whether from a 

 specimen actually native or an accidental cabinet specimen is not 

 known. It has, however, been taken in numbers bv Mr. Otto Luefsfer 

 near Baltimore. It is widely distributed in Europe. 



