. Annual report - Entomological Society of Ontario. Entomological Society of Ontario; Insect pests; Insects. 43 3rd of May; from that date until the end of June they were very abundant, and from the careful examination of many seed-heads towards the end of that month it was- estimated that, while five-sixths of the clover seed had been destroyed by the midges, four-fifths of the midges had been destroyed by this parasite. Thus through the good offices of this one species of parasite the prospective numbers of the next brood of midget were reduced to the extent of 80 per cent. The second parasi
. Annual report - Entomological Society of Ontario. Entomological Society of Ontario; Insect pests; Insects. 43 3rd of May; from that date until the end of June they were very abundant, and from the careful examination of many seed-heads towards the end of that month it was- estimated that, while five-sixths of the clover seed had been destroyed by the midges, four-fifths of the midges had been destroyed by this parasite. Thus through the good offices of this one species of parasite the prospective numbers of the next brood of midget were reduced to the extent of 80 per cent. The second parasite, P. error, develops more slowly, and remains within the body of the midge larva until after it has escaped from the clover head, entered the ground, and spun its cocoon; then the full-grown parasite, having destroyed its host, eats its way through the cocoon and escapes. This has been found as yet only in specimens of the midge larva received from Yates County, New York State. THE CLOVER ROOT-BORER—^2/^as^«« trifolii, Muller. This is another new pest—a small beetle about one-twelfth of an inch long, belonging to the family usually known as Bark-borers, Scolytidce, from their habit of boring irregular channels through the inner bark of various trees. This species, however, is a root-borer. The beetle is of a reddish-brown colour, coarsely punctured on the body, not so coarsely punctured on the head and thorax, with the whole body more or less hairy. They usually reach maturity in October ; and the beetles hibernate in the root and probably live upon the root. Early in spring they leave their hiding-places, and, after pairing, the female proceeds to deposit her eggs. The insect in its various stages is represented in the accompanying figure, 15 : d shows the beetle; 6, the larva as found in the burrows; c, the pupa, which is usually found lodged in a cavity at the bottom of the burrow; the figures are about ten times their natural size. At a a «, the destructive work of
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectinsects, bookyear1872
