110 WOBK AT HOME AND IN THE FIELD 



chisel, and examine both its inner surface and the wood from which 

 it was removed. The wood thus exposed may reveal openings 

 of the galleries of wood-eating larvae, in which case, unless the 

 material is too hard to be broken up with the chisel, you may be 

 able to trace out a few pupae. Where these exist, they are usually 

 to be found very near the entrance, sometimes even protruding 

 slightly from the opening, for the larvae generally place themselves 

 in this position of easy escape when about to change. 



Next give your attention to the moss, if any, covering the lower 

 portion of the trunk. This affords a very favourite shelter to 

 many species. Tear it off very carefully, beginning at the top, and 

 watch for loose pupae and cocoons as you do so. Then hold the 

 clumps you have removed over a patch of bare ground or over a 

 spread handkerchief, and pull it to pieces, in order that any pupae 

 it contains may fall out ; also examine the fragments carefully for 

 others that may remain attached. 



This done, the surface of the ground must be examined. 

 Remove all dead leaves, and watch for pupae that may be sheltered 

 beneath them. If any loose stones lie on the ground, turn them 

 over. Search well into the angles between the roots, and if there 

 are any holes or hollows beneath them or in the trunk itself, pull 

 out all loose matter within, and feel gently above and around for 

 cocoons. 



After all loose matter has been removed, there still remains the 

 soil for examination. If this is very hard and clayey, it is proba- 

 bly useless to carry the search any farther ; also if very wet you 

 need not expect much ; but if comparatively dry and friable there 

 are more hopes of success. 



As a general rule the north and east sides of the trunk are 

 drier than those which are exposed to the heavy rains brought 

 by the south and south-west winds, and are consequently more 

 favoured by larvae that are seeking a resting place for the winter. 



Most larvae seek shelter in the angles between the roots of the 

 trees on which they fed, but a few species seem to prefer the 

 edges rather than the corners ; and in cases where no such angles 

 are formed at the surface, you will do well to examine the earth 

 and turf all round the trunk ; but it is generally useless to extend 

 the search more than a few inches from the tree. 



After having searched every available nook and corner as far. 

 as possible without digging, thrust the trowel obliquely into the 

 soil a few inches from the tree, turn over the sod, and then 



