96 INSECTS INJURIOUS TO FRUIT. 



Not one of the white moths that are now so numerous the mature insect from the 

 army of caterpillars that made such sad havoc with the foliage of our fruit trees a 

 month ago. The flies I have not yet examined closely. Many of them are the 

 blue and green bottle-flies, the maggots of which are the consumers of decaying ani- 

 mals. A very large proportion were those flies that extend their wings out at right 

 angles from the body, and have brown heads and bodies. These breed in and con- 

 sume the filth about our houses and barns. I noticed some varieties of the sulphus- 

 fly that deposits its eggs in colonies of plant lice, on which the young maggot feeds, 

 and thus befriends the gardener. Many also of the parasitic class, that deposit their 

 eggs on the sides of large caterpillars, near the head. The young from the eggs eat 

 into these caterpillars, and, there feed upon their living flesh, finally destroying 

 them ; and these also are often our friends. The lace-wing is also an enemy to the 

 plant lice. The wasp's reputation is equivocal. He destroys insects, but will also 

 eat our ripe fruits. 



In order to make a more exact test, I repeated this experiment for twenty-four 

 hours. The number of victims was 281. The kinds of insects were about the 

 same, and nearly in the same proportions as at first. To this statement I find 

 appended in my diary the following observations : " This is a poor business, and I 

 shall stop it What right have I to destroy these hundreds of flies, when we are cer- 

 tain that most of them are useful, and we do not know that any of them are injurious! 

 If I had found the Curculio, Apple Moth, Aphides, Pear or Apple Tree Borers, or 

 Mosquitoes in any proportion to the vast army of this pest now filling the air ; had the 

 flies been of the kind that annoy us in the house, or had I caught the moths of the 

 caterpillars that have been so troublesome, there would have been some excuse. 

 But this is like firing into a crowd of friends in hopes of killing an enemy." 



Aug. 13, 14, and 15. Am passing a few days in the northern part of New 

 Jersey, to escape the distressing heat of the city. I spend hours in the old orchards- 

 Have been cutting the blighted apples till knife and hands are black and sticky with 

 the juice. Find no grubs of the Curculio, but thousands of their marks. The cres- 

 cents had been made, the eggs deposited, most of them had been hatched, and the 

 young Curculio had started on its rambles towards the centre of the fruit. Its path- 

 way could be traced by a brown or green mark, as seen in Plate 5, Figure 4. This 

 mark is not visible when first made ; but, like a wound in the flesh of the apple 

 from any cause, soon becomes discolored. My experience here was similar to that 

 in Mr. P.'s orchard in Newark. The grubs of the Curculio were nearly all dead. 



Aug. 16. I have seen an old apple orchard to-day so different from others in 



