INSECTS INJURIOUS TO STONE FRL1TS 



651 



larva in silken-lined cells or burrows in the spongy tissue of the 

 bark at the crotches of the limbs. Their presence is indicated 

 by small mounds of comminuted bark, as shown in Fig. 503, at a 

 and b. Early in the spring, as the foliage is putting out, the 

 larvae begin to leave their burrows and attack the tender shoots, 

 boring into and down the pith, the galleries ranging from about 

 one-third inch to 1^ inches in length. The shoot thus injured 

 soon wilts and dies, as shown in Fig. 504, at a. Many shoots may 

 be attacked by a single larva 

 which is thus capable of doing 

 considerable harm. There are 

 two or three generations of 

 larvae during the summer in 

 the West, those of the second 

 and third attacking the fruit, 

 the later varieties being the 

 worst injured. According to 

 Professor C. V. Piper, the 

 larva enters the peach at the 

 stem end, usually boring into 

 the pit, the seed of which it 

 seems to prefer, usually caus- 

 ing the stone to split as the 



FIG. 502. The peach twig-borer 

 (Anarsia lineatella) : adult moth 

 with wings spread and folded 

 much enlarged. (After Marlatt, U. 

 S. Dept. Agr.) 



fruit 'ripens; or simply the 

 flesh may be tunnelled, de- 

 pending on whether or not 

 the stone is hard, when the fruit is attacked. In California, 

 according to Clarke, the larva usually enters the fruit along the 

 suture at the stem end, and excavates a chamber beneath the 

 skin, which blackens and shrivels somewhat, affording entrance 

 to organisms of decay. In the ripe fruit the larva) fre- 

 quently make their way to and around the stone, which, 

 if split, may be entered and the seed fed upon. . . . Early 

 in the fall, about September 1, in California, the very young 

 larvae from eggs of the last generation of moths construct 

 their hibernation cells in the soft tissue of the crotches of 



