For list see Scott, Ent. Mag. xviii. 1882, p. 253.
There is some doubt on this point, as the earlier observers seem to have supposed that a winged individual appearing in a generation chiefly apterous was ipso facto, a male; it seems, however, to be certain that perfect winged males appear in some species in generations producing no perfect sexual females. Speaking generally, the course of events seems to be that in summer there exist only wingless and winged parthenogenetic females, and that the sexually perfect forms appear for the first time in autumn.
Mitt. Schweiz. ent. Ges. iv. 1876, p. 529.
The term pseudovum is applied, as a matter of convenience, to the earlier condition of the viviparously-produced form, and the term pseudovarium to the ovary producing it.
Balbiani, Ann. Sci. Nat. Zool. (5) xi. 1869, p. 29. For concise recent remarks on the early embryonic states, see Lemoine, Bull. Soc. ent. France, 1893, p. lxxxix.