98 



QUINCE CULTUliE. 



insect, in all its stages, will be readily recognized by the 

 accompanying illustrations. 



During the months of May and June this beetle 

 emerges through a round hole, having completed all its 

 changes from the egg to the imago. It comes out in the 

 night, and hides during the day among the leaves, which 

 are now its food. The sexes pair at night, after which 

 the female deposits her eggs in the bark at the collar of 

 the tree. The eggs are the size of a small pin-head, and 

 may be looked for from May till August. Their entire 

 life history embraces about three years. Within about 



Fig. 67. Larva. Fig. 68. Chrysalis. Fig. 69. Beetle. 



ROTJND-HEADED APPLE-TREE BORER. 



two weeks from the laying of the eggs, they hatch into a 

 larva, which penetrates through the bark to the sap-wood 

 the first season, where they form a burrow, and may 

 often be detected by the discolored appearance of the 

 bark of young trees, or by the fine-grained castings they 

 have pushed out of their holes. They remain in the tree 

 three years, becoming each year more destructive. Be- 

 fore the end of this time, as they approach the comple- 

 tion of their larval growth, they cut a passage through 

 the heart-wood of the tree, extending it outward to the 

 bark. These passages are cut very direct up to this 

 point for a future exit, or they may be found turning 

 abruptly back in any direction. "With an instinct bor- 



