544 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 



ward from this channel, the larval channels constantly enlarging dur- 

 ing the larval life, and sinking a little deeper in the wood as the pupa 

 state is reached. These larval channels are from 5 to 45™™ in length, 

 and from one-third to 1""" in width. The central channel is usually 

 slightly sinuous, being governed to some extent by the surface of the 

 wood and the number of beetles at work, they never coming in contact. 

 At about midway of the central channel there is in every instance a 

 change of direction— a curve sometimes hardly perceptible, at other 

 times and usually very marked. The lateral larval channels extend 

 outward at right angles from the central channel, and are about one- 

 third the length of the former, that varying from one to three inches 

 in length. 



" In November, 1885, live specimens of this insect were taken from 

 ash trees in the western part of Davis County. The bark of these 

 trees had apparently been abraded about a month previous, and had 

 been at once attacked by Hylesinus aculeatus. Large numbers of these 

 had eaten their way from one-fourth to one inch under the bark from the 

 point of entrance and had gone into similar quarters." (Ent. Amer., li, 

 1886, p. 76.) Mr. W. L. Devereaux, of Clyde, N. Y., writes me regard- 

 ing this beetle as follows : 



Hylesinus aculeatus does not operate on living trees in its larval state, but the 

 beetles do, and of course the more ash trees cut for rails, etc., the more rapidly will 

 the beetles increase. 



Beetle. — In Hylesinus the tibiae are serrate ; the autenual club elongate-oval, 

 pointed, not compresed ; in H. aculeatus the club of the antennae is elongate-fusiform, 

 the bands of the elytra oblique, while the sides of the prothorax are smooth (not 

 rauricate, as in the closely allied H. imperialis of Dakota and Arizona). Length, 2.2 

 to 3.4">"> (.09 to .13 inch). It ranges from Massachusetts to Texas, Kansas, and 

 Oregon. (Le Conte.) 



9. Hylesinus opaculus Le Conte. 



This timber borer has been found by Mr. E. A. Schwarz, living 

 under the dry bark of elm and ash trees. See fig. 72, p. 227. 



Beetle. — Body elongate, clothed with short, erect yellow hair without scales. Length, 

 2 to 2.5""" (.08 to .10 inch). (Le Conte). According to Riley it differs from the clover 

 beetle (H. trifolii) in the shape of the antennaj, the visible labrum, and other points 

 shown in Fig. 72. 



AFFECTINa THE LEAVES. 



10. The ash saw-fly. 

 Selandria barda{8iiy.) 



The larvpe of this saw-fly are said by Mr. H. Osborn to at times injure 

 the ash in Iowa. The adults have not been reared, but he feels sure 

 that the larvae were of the above species. The eggs are deposited in 

 rows along the sides of the petioles just beneath the outer bark, and 

 so neatly that it is almost impossible to detect any break in the epi- 

 dermis. Usually there are from six to ten on a leaf. They evidently 

 increase much in size before hatching, pushing the bark up in a blister- 



