. Annual report. Entomological Society of Ontario; Insect pests; Insects -- Ontario Periodicals. 5S suckers. As soon as the ground thaws and the sap starts in the spring, these young lice work oflf their winter coat, and, growing apace, commence to deposit eggs. All, without ex- ception, become mothers, and assume the degraded form (a) already described. Fig. TvpK Kadicicola :—a, shows a healthy root; 6, one on which the lice are workiDg, re- presenting the knots and swellings caused by their pmictures ; c, a root that has been deserted by them, and where the rootlets have commenced to d
. Annual report. Entomological Society of Ontario; Insect pests; Insects -- Ontario Periodicals. 5S suckers. As soon as the ground thaws and the sap starts in the spring, these young lice work oflf their winter coat, and, growing apace, commence to deposit eggs. All, without ex- ception, become mothers, and assume the degraded form (a) already described. Fig. TvpK Kadicicola :—a, shows a healthy root; 6, one on which the lice are workiDg, re- presenting the knots and swellings caused by their pmictures ; c, a root that has been deserted by them, and where the rootlets have commenced to decay ; rf, rf, rf, show how the lice are found on the larger roots ; e, female pupa, dorsal view ; /, same, ventral xiew ; ;;, winged female, dorsal view ; h, same, ventral view ; i, magnified antenna of winged insect;.;', side view of the ^vingless female, laj-ing eggs on roots ; k, shows how the punctures of the lice cause the larger roots to rot. " At this season of the year, with the exuberant juices of the plant, the swellings on the roots are large and succulent, and the lice plump to repletion. One generation of the mother form (a) follows another—fertility increasing with the increasing heat aud luxuriance of summer—until at last the third or fourth has been reached before the winged form (b) makes its appearance in the latter part of June or early in July. Such are the main fea- tures which the development of the insect presents, to one who has studied it in the field as well as in the closet. "Since I proved, in 1870 (adds Mr. Eiley), the absolute identity of these two types by showing that the gall-lice become root-lice, the fact has been repeatedly substantiated by dif- ferent observers. Yet, strange to say, no one has heretofore succeeded in making gall lice of the young hatched on the roots, though I formerly supposed that Signoret had done so. It is, therefore, with much satisfaction that I record the fact of having succeeded this winter in ob- ta
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectinsectp, bookyear1872
