MICHIGAN STATE POMOLOGICAL SOCIETY. 321 



5, a) incloses itself in a tough little yellowish cocoon of silk 

 (Fig. 5, b), then gradually assumes the pupa state (Fig. 5, c), 

 and at the end of about the same length of time that the Cur- 

 culio requires to undergo its transformations and issue as a 

 beetle, this, its deadly foe, gnaws a hole through its cocoon 

 and issues to the light of day as a black four-winged fly (Fig. 

 4, a, male ; b, female). In the vicinity of St. Louis, this fly 

 was so common the past season that, after very careful esti- 

 mates, I am satisfied three-fourths of all the more early 

 developed Curculio larva) were destroyed by it. On the 17th 

 and 18th of April, in that locality, a severe frost killed the 

 peach buds on all but a few of the young and most vigorous 

 trees of Hale's Early and Crawford, so that instead of a large 

 and abundant crop of peaches to depredate on, the little Turk 

 had to concentrate its attacks on the few peaches that were 

 left ; and no one expected that any fruit would be saved. Yet 

 the work of this little parasite was so efiectual that, wherever 

 fruit set, n fair crop was gathered even by those who made no 

 effort at all to protect their trees ! 



While visiting Dr. Fitch last August, at his house in Salem, 

 N. Y., I compared my bred specimens with his sj)ecies, and 

 found them identically the same ; but I shall, in this reading, 

 omit the description which follows and which may be read, by 

 those interested, when this essay is published. 



As Mr. Walsh bred this same parasite from the larvse of his 

 little Plum Moth, it doubtless attacks other soft-bodied larva) 

 and does not confine itself to the Plum Curculio. This is the 

 more likely, as it would scarcely pass the winter in the fly 

 state. The female, with that wonderful instinct which is 

 exhibited in such a surpassing degree in the insect world, 

 knows as well as we great Lords of Creation what the little 

 crescent mark upon a peach or plum indicates; and can doubt- 

 less tell with more surety, though she never received a lesson 

 from her parents, whether or not a Curculio larva is drilling 

 its way through the fruit. When she has once ascertained the 

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