Page:Phylogeny of cynipid genera and biological characteristics.pdf/15



A large proportion of the Cynipidæ reproduce agamically. There can be little question of the non-existence of the males of many of the species. Hartig (1840) bred almost 10,000 individuals of a single species, Dryophanta disticha, and secured only females. In spite of extensive collecting and breeding of many species of gall-wasps, both in Europe and America, no males have been found for some of them, and Adler (1881) and other workers have regularly secured galls and mature insects from the eggs of these agamic females.

The successive generations of some species are all similar and agamic; Adler found this to be the case with five species, each of which he bred for two successive generations—for three generations in the case of Andricus serninationis. In the case of other species, most likely for the