COLEOPTERA SCOLYTID^E. 



103 



and whip clothed with long ciliate hairs. The elytra are very coarsely 

 striated, thus imparting to the insect a rather rough appearance. 

 The legs are generally pitchy hlack. 



The larv are long, legless, white maggots, with brown head and 

 jaws. They pupate just immediately beneath the outer skin of the 

 rough bark, so that in looking for the full-fed larvae we must dig very 

 lightly. 



To prevent the spread of this insect, it is best to cut down all 

 back-going old trees with very rough bark ; 

 and this is in keeping with good forestry, 

 as an ash-tree, above all others, depreciates 

 very rapidly in value if left standing after 

 it has reached maturity. 



Hylesinus fraxini (Fabr.) 



This species is commonly known as the ash" 

 bark beetle. Miss Ormerod, in her valuable 

 work, says : " The beetles are often attracted 

 in large number by newly felled ash trunks, 

 in the bark of which they propagate, and 

 from whence the new brood spreads to 

 the neighbouring trees, mainly attacking those that are sickly or 

 decayed, or young trees, which they sometimes injure to a serious 

 extent." So far as my experience and personal observations go, 

 I have found that the beetles only attack very sickly or half-dead 

 trees, but never healthy or young ones. When marking trees in 

 Cheshire, I have observed the dead standing trees had been attacked 

 by the beetle, but this had always been done just when the trees were 

 in a half-dead condition. 



The life-history of this beetle is very easily followed. About the 

 end of March or the beginning of April the beetles emerge from their 

 winter quarters, and are attracted in considerable numbers to newly 

 felled trees or poles. In Cheshire I always discovered this species 

 on comparatively large stems, but in the south of England they are 

 very common on poles. The female beetle generally appears before 

 the male. She then commences to make a straight tunnel, and on 

 the appearance of the male, copulation takes place. The female 

 makes her tunnel perpendicular with the stem, deposits her eggs, 



Fig. 94. Hylesinus crenatus, 

 (From Fisher's ' Forest Pro- 

 tection.') 



