312 



WEST VIRGINIA EXPERIMENT STATION. 



Fig. LX. Adult of European bark beetle destroyer 

 feeding on bark beetle. 



to me that they 

 were alone capable 

 of preventing an ex- 

 cessive increase of 

 the bark beetles, 

 (see Fig. LX,) and 

 thus prevent an ex- 

 tension of their rav- 

 ages beyond the in- 

 jured and felled 

 trees. In many in- 

 stances noted, the 

 Clerid has so com- 

 pletely destroyed 

 (he young or larvae 

 of the bark beetles 

 that but very few 

 matured examples 

 could be found in 

 otherwise would have contained 



the bark of the trees which 

 many thousands. 



It was also evident that had it not been for the beneficial in- 

 fluences of the Clerid in this forest where so much broken tim- 

 ber occurred, that the numbers of bark beetles would have 

 been sufficient to attack and kill the uninjured trees, as our 

 Dendroctonus was doing in West Virginia. 



Fig. XLI. Mouth parts of adult of European bark beetle destroyer. 



The injured trees were being rapidly worked up into lumber 

 and fuel, in order to destroy the bark beetles and thus avoid a 

 possible invasion by them the following spring, but I was con- 

 vinced from what 1 had seen that while this was apparently an 



