Bui. 1107, U. S. Dept. of Agriculture. 



PLATE IV. 



'M%m 



Fig. 1. — Infested section of oak covered with 

 alloys and building paper in layers, but with 

 narrow strip of sheet steel that was placed 

 between layers of lead alloy and top layer of 

 alloy removed. Shows beetles in holes where 

 they were stopped by steel . Photograph by 

 H.E.Burke. 



Fig. 2.— Section of infested oak with all the 

 layers of alloy removed, showing how many 

 of the beetles attempted to escape from the 

 sides instead of boring through the alloys. 

 Photograph by H. E. Burke. 



Fig. 3. — Infested section of oak covered with 

 alloys and building paper in layers. Beetles 

 have emerged through aU except where nar- 

 row strip of sheet steel was placed between 

 layers of lead alloy. Photograph by H. E. 

 Burke. 





Fig. 4. — Same as Figure 1, except that next layer 

 of aUoy has been removed. The larger hole 

 was made by the round-head borer Xylo- 

 trechus nauticus. Photograph bj' H. E. Burke. 



THE LEAD-CABLE BORER. 



