COLEOPTERA. 91 



is about an eighth of an inch long, and of a dark- 

 reddish colour. This beetle is terribly mischievous in 

 granaries. 



Another, destructive on a grander scale, is Scolytus 

 destructor, a little cylindrical, brown, wood-boring beetle, 

 which attacks elm-trees. In the London parks, in the 

 Champs Elysees of Paris, and indeed wherever these beau- 

 tiful trees are to be found in their glory, there the ravages 

 of this minute enemy have been conspicuous. For many 

 years a controversy was carried on as to whether the 

 presence of these beetles was the cause or the effect of 

 disease in the trees, but the question seems to have been 

 set at rest in a most satisfactory manner by the investi- 

 gation and experiments of Captain Cox (see the " Zoolo- 

 gist" for 1858, p. 5995), who, by the simple expedient of 

 spoke-shaving the outer bark down to the mines of the 

 Scolytus, and destroying the larvae, entirely restored 

 seventeen out of eighteen trees in the Regent's Park 

 assigned to him for experiment by the " Woods and 

 Forests." Many trees in the park had died, and were 

 dying, prematurely, and of the eighteen chosen some 

 were slightly injured, some " very severely," and some 

 " most severely." The greater part of these were re- 

 covered by his treatment in the course of five years, in 

 six all were perfectly healthy, with the exception of one 

 which was too far gone for restoration. 



There are several other species in this family which 

 attack the bark of various trees. The pine forests of 

 Germany afford an example of what it is in the power of 

 these small creatures to effect. It is recorded that in one 

 year (1783) more than a million and a half of trees were 

 destroyed in the Hartz Forest alone. 



The mines of different species have a marked cha- 



