. Circular. Insects. 5 drops to the ground, into which it usually descends a short distance. Here it forms a tough silken cocoon, to which particles of earth adhere, giving it the superficial appearance of a little lump of soil. From the cocoons the adults emerge in time to oviposit in the second or seed crop of bloom, and the same mode of procedure is gone through with again, except that this time the insect hibernates in the cocoon and the midges do not appear until the following spring. It will thus be observed that there are two annual generations, the flies appearing simultaneously with t
. Circular. Insects. 5 drops to the ground, into which it usually descends a short distance. Here it forms a tough silken cocoon, to which particles of earth adhere, giving it the superficial appearance of a little lump of soil. From the cocoons the adults emerge in time to oviposit in the second or seed crop of bloom, and the same mode of procedure is gone through with again, except that this time the insect hibernates in the cocoon and the midges do not appear until the following spring. It will thus be observed that there are two annual generations, the flies appearing simultaneously with the first and second blooming periods of the clover. While they thus appear earlier in the South than in the North, it is doubtful if there are more than two broods throughout the area over which red clover (Trifolium pratense) is grown, though the broods may be more prolonged or widely sep- arated to the southward. EFFECT UPON THE PLANT. There is no material effect on the stem or foliage, but the heads quickly indicate the presence of the maggots by failure of the florets to develop, becoming reduced in size, often distorted, and lacking the familiar pinkish color more or less. In fact, the abundance of the pest may be approximately estimated by the appearance of a clover field during the blooming season. DISTRIBUTION. Although the pest did not attract more than local atten- tion until 1878 and was not described until a year later, there is considerable evidence indicating that it was injuri- ous in New England at least thirty years prior to these dates. Dr. S. A. Forbes, also, found good evidence of its occurrence in Illinois at about the time of its discovery in New York by Lintner. One of the writer's assistants, Mr. (i. I. Reeves, found it occurring in Nebraska in destructive abundance in 1904, though Prof. Lawrence Bruner did not know of its occurrence in that State in 1898. The late Miss Ormerod reported its occurrence in England in 1890 and stated that it had probably be
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