HYLASTES CUNICCLARIUS, ER. 



279 



ground, is the young coniferous plantation. Here, if the 

 beetles are newly emerged and sexually immature, they feed 

 to develop their reproductive faculties (" reifungs-frass ")or, if 

 mature, to recuperate after their first breeding period 

 (" ernahrungs-frass "). It is this "feeding," or " frass," which 

 makes H. cunicnlarius the enemy of the forester. It attacks 

 young, recently-planted conifers just below the root-collar, 

 gnawing away the bark, girdling 

 the root-stem, and by preventing 

 the sap-flow causes the young 

 trees to wilt and die. 



Figure 3 shows the lower por- 

 tion of a young (four-year-old) 

 Scots pine destroyed by the adult 

 ainicularius. On the plant from 

 which Fig. 3 was made five //. 

 cutiicularius and two H. ater were 

 feeding. The gnawed portions of 

 the young plant are unshaded in 

 the figure. 



Often H. cimicularius is accom- 

 panied by the large Pine Weevil, 

 Hylobius abietis, L., which gnaws 

 the bark of the young plant above 

 ground. In fact, so common is 

 this association of H. cunicu- 

 lariiis and the Weevil that, until 

 recently, I was inclined to con- 

 sider the Scolytid was a follower 



of the Weevil, which is much the more common beetle 

 and is, in fact, our worst forest pest. That H, cunicularins 

 is, however, primarily destructive I have now abundant 

 evidence. 



Fig. 3. Lower Portion of young 

 Scots Pine, showing " frass " of 

 H . cunicnlarius. 



Relations to the Forest. 



The relations of H. auiicuhxrins to the forest can, I think, 

 best be illustrated by the description of an attack by it. 



On 7th October 191 5, on Darnhall Estate, Peeblesshire, I 



