252 WEST VIRGINIA EXPERIMENT STATION. 



entrance to the vital parts of the bark. Between 1891 and 1894, 

 this beetle became less abundant and in some sections of the 

 forest was quite rare, but during the past year I found it to be 

 again quite common. 



So far as I have observed it confines itself entirely to the 

 spruce. 



Very little appears to have been published with reference to 

 the life history and distribution of the species, except that 

 recorded by Le Conte who described it from specimens collected 

 in the mountains of Pennsylvania, and later, he recorded it from 

 the District of Columbia. 



THE COSMOPOLITAN SPRUCE BARK BEETLE. 



This bark beetle is of especial interest, since it has been de- 

 termined that the examples collected in this country are iden- 

 tical with those from Europe where it is widely distributed 

 and a common enemy of the Norway spruce. It was described 

 as early as 1837 by Ratzeburg in his great German work on 

 forest insects. 



It was possibly introduced into America with young Norway 

 spruce trees imported from Europe at a very early date, since 

 it is now widely distributed over North America, it having 

 been recorded by Le Conte in 1868 from Alaska and Hudson 

 Bay to Virginia. It is considerably larger than its near rela- 

 tion, Le Conte's spruce bark beetle, and darker in color, yet of 

 similar form and general appearance. Its habits, while similar 

 to those of the other spruce bark beetles, so far as mining in the 

 bark and development of broods is concerned, differs in its pre- 

 ference for the bark at the base of the tree or stumps, and even 

 that of the roots of the latter, in which I have frequently found 

 it in abundance, both in the exposed roots, considerable dis- 

 tance away from the base, and in those several inches below 

 the surface of the ground. This habit of attack, together with 

 the fact that I have frequently found it in living bark on stumps 

 and logs of recently felled trees, as well as in that of recently 



1 Dryocoetes autographus, Ratz. 



