THE CHEERY FRUIT SAWFLY. 77 



orchard under observation there were early and late blooming cherries 

 in alternating rows. Eggs of this insect were numerous and a few 

 larvae present before the adults apparently noticed the later-blooming 

 varieties. Afterwards, when the petals of the Royal Anne cherry 

 were beginning to open, eggs were just being deposited in numbers in 

 this variety while the Black Tartarians immediately adjoining these 

 trees had shed the petals and the larvae had mostly hatched and only 

 very rarely could an egg be found. The time required for incubation 

 of the egg is practically the same in all varieties of fruits. Ordinarily 

 only one egg is deposited in a single flower. Occasionally, however, 

 two and very rarely three eggs were found in the sepals and calyx of 

 one flower. 



THE LARVA. 



Upon hatching the young larva may feed for a short time in the 

 tissue immediately surrounding the egg cavity, or on the inner sur- 

 face of the calyx cup, but it soon finds its way to the bottom of the 

 calyx cup and eats directly into the newly formed cherry. The larva 

 at this time almost always enters the fruit through the base imme- 

 diately adjoining or very near the stem. Going directly to the center 

 of the cherry, the larva eats away the small kernel. The cherry thus 

 injured soon withers. In two to four days after entrance the larva 

 makes its first molt and leaves this cherry in search of other and fresh 

 food. When attacking the second cherry the larva may enter the 

 fruit through almost any place on the surface but invariably goes 

 directly to the seed, and if this has not hardened eats out the kernel, 

 as was done with the first fruit, seeming to prefer this to the meat of 

 the cherry. The second cherry, being larger when attacked, usually 

 withstands the effects of feeding longer and the larva may remain inside 

 for some six to ten days or even longer. The growth of the cherry is 

 checked and it frequently hangs on the tree retaining a rather pale 

 green color for some days after growth ceases and the fruit has 

 shriveled. When the kernel in this second cherry has been destroyed 

 the larva usually goes to a third cherry and if the pit has not hardened 

 eats it out as before. However, when the pits become too hard the 

 larva feeds on the meat of the cherry near the pit until it attains full 

 growth in much the same manner as does the plum curculio in peaches. 

 In Plate IX are shown photographs of the injured fruit and the 

 entrance and exit holes of the larvae. 



Each larva usually destroys three cherries, although some go to the 

 fourth, while a very few complete their growth in the second cherry. 

 The time required for the larvae to attain their full growth averages 

 from 22 to 26 days. In Table I the record is given for 34 individuals. 



