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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1898 Excerpt:...leave the cocoons and when these unfertilised females have been examined after oviposition no traces of spermatozoa were discovered in the ovaries, while they are easily seen in those that have been fertilised. The first statement made by Cameron was subsequently modified, for in the Appendix to Vol. I. of his Monograph (p. 218), he says that the virgin females of Abia fasciata and N. ribesii yielded males and females. In N. rufa, etc., male and females were also produced, but in Hemichroa rufa, Eriocampa ovata, Ncmatus appendiculatus and others without exception females only were bred. Not only can this parthenogenesis last for one generation, but in one species at least (A. fasciata) Dr. Osborne has shown that a third generation may be obtained without any male connection. Prevention and Treatment of Currant and Gooseberry Sawflies. The attack of different Sawflies on gooseberry and currant is usually fairly persistent. Year after year certain gardens, and even certain parts of a garden, are ravaged by one or other of these pests. This is when no steps are taken to check the increase of the insects, which in nearly all cases pupate in the earth beneath the bushes. From these pupae the adults emerge close to the food plant of their future progeny, and thus can readily deposit their eggs. It is therefore very desirable to check this increase, or to try and exterminate the pests when in their winter quarters. This can be done in two ways: (i) by removal of the earth and pupae. (2) by applying some caustic substance to the ground in which they are present. Removal of surface soil during the winter and burning it or burying it deeply, whilst the fresh soil taken from the hole is placed beneath the bushes, is an excellent plan, and may well be practised when th...