288 NEW YORK STATE MUSEUM 



Dark elm bark borer 



Hylcsi)ins opaciilus Lcc. 



Making small, pinholelike perforations in elm, particularly diseased bark in August 

 and September, a minute, cylindric, dark brown bark beetle about '/o inch long, its wing 

 covers marked with deeply impressed, punctured furrows and bearing short hairs. 



This species mines under the green bark of ehns, particularly th^se in 



a sickly or thing condition. It is not, as a rule, injurious. 



Description. This beetle has been described by Dr LeConte as follows : 

 " Cylindrical, brownish black, opaque, thinly clothed with short stiff yellow 

 hairs ; antennae and feet ferruginous ; head convex, thickly punctured ; 

 prothora.x nearly as long as wide, narrowed in front, side subsinuate near 

 the tip ; densely but not finely punctured, with a very narrow faint dorsal 

 carina ; elytra with striae composed of deep subquadrate punctures, inter- 

 vals narrow, rough with transverse rugosities." The antennal structure is 

 shown on plate 67, figure 6. 



This species has been recorded from the .Middle .States and Pennsyl- 

 vania by Dr LeConte, and Dr Smith lists it from New Jersey, where it is 

 said to mine the green bark of elms. 



Ash timber beetle 



r{\lcsi)iiis at II /ca his .Say 

 A small, brownish, rather stout, cylindrii beetle bores commonly in freshly cut asli. 



This species is our most common ash borer, and specimens may be 



found wherever ash posts have been split in the spring of the year. The 



main adult burrow is usually excavated in the inner bark and sapwood by 



two females working in opposite directions from the entrance point, which 



latter is usually indicated by a slight notch. The compound main gallery 



is from about i inch to nearly 4 inches in length, and eggs are deposited at 



short intervals on each side, young larvae making their gradually dilated 



burrows at appro.ximately right angles to the parental groove. The lateral 



burrows are from about ^ to nearly 2 inches in length. 



Description, This beetle has been described by Zimmerman as follows : 

 "Of the same form as the European H. fraxini but sinaller ; blackish 

 brown, thickly clothed with very short ashy squamiform hairs; antennae 



