Chapter I: Parthenogenetic and Sexual Egg 339

The process of the formation of polar bodies very 339
widely distributed

The significance of polar bodies according to 340
Minot, Balfour, and van Beneden

My hypothesis of the removal of the histogenetic 341
part of the nucleus

Confirmation by the discovery of polar bodies in 345
parthenogenetic eggs

Parthenogenetic eggs form only _one_ polar body, 346
while eggs requiring fertilization form _two_

Parthenogenesis depends upon the fact that the 348
part of the nucleus which is expelled from sexual
eggs in the second polar body, remains in the egg

History of this discovery 349