Destructive Forest Insects of Dumfriesshire. 263 



over some sawdust is very- successful. The beetles shelter in the 

 sawdust and can be collected and destroyed. But prevention is 

 better than cure. Destroy the breeding places, viz., the bark on 

 the roots of felled trees, either by lighting fires over the roots or 

 stripping it off and burning it. On a bright sunny day the beetles 

 can be picked from the trees. The beetle is dull black in colour 

 with several yellow spots forming bars on its elytra. These 

 spots, through a magnifying glass, are seen to be composed of 

 hairs. 



Pissfldes Pini. — This insect is very much like the Pine 

 Wee\il, in fact it is often mistaken for a small specimen of the 

 latter. The main difference lies in the position of the Antennae. 

 Those of the Pine Weevil are situated at the extreme end of the 

 rostrum, while those of the smaller beetle are halfway down. 

 Pissodes Pini cannot be classed as a very destructive insect as the 

 larva2 which do the most damage are generally found on dead or 

 dying trees. The mature insect is to be found most often in saw- 

 dust piles. 



Bark Beetles. 



Hyhsinus Fraxini. — This beetle is generally found on dead 

 or back-going ash trees, and their markings on both bark and 

 wood are very pretty. The centre gallery is made by the female, 

 who lays her eggs to the right and left. On hatching out the 

 larvfe bore at right angles to the mother gallery, and after pupa- 

 tion make their exit through the bark and fly awav to healthy ash 

 trees, where they bury themselves in the bark and hibernate there, 

 emerging in March and April, when they fly to some dying tree to- 

 breed. 



Hylurgus Piniperda. — This is another of the forester's worst 

 enemies. In April they withdraw from their winter quarters 

 (generally in young shoots) and fly to a sickly or dying tree. The 

 female burrows into the bark, and then upwards partly in the bark 

 and partly in the cambium, laying eggs as she goes. The larvse 

 hatch out in from 10 to 20 days and proceed to eat their way, at 

 first at right angles to the mother gallery afterwards in all 

 directions. Pupation takes place at the end of the larval 

 galleries. After pupation the mature beetles escape by making 

 exit holes through the bark. The damage done by these insects 

 is confined to this stage. The beetles bore into the leading shoots 



