The Biology of Microplectron fuscipennis, Zett. (Chalcid.), a Parasite of the Pine Sawfly (Diprion sertifer, Geoff.)

Abstract

Cocoons of Diprion sertifer, Geoffr., containing nearly eight millions Microplectron fuscipennis, Zett., were collected in Europe in 1934 and despatched to Canada for the control of the Spruce Sawfly, Diprion polytomum, Htg.This parasite is widely distributed throughout Europe as a primary parasite of several species of pine sawflies of the genus Diprion.A full account of the biology and a detailed description of the various stages is given.In the laboratory it was reared in large numbers on the cocoons of D. polytomum from Canada.Its chances of success in Canada depend on its acclimatisation and the accessibility and quantity of host material. Its tremendous fecundity and rapid rate of increase are greatly in its favour.