The New Student's Reference Work/Apogamy

Apogamy (á-pŏg′á-my). In plants with regular alternation of generations (which see) the gametophyte produces the sporophyte by means of a fertilized egg. Occasionally the sporophyte is produced directly upon the gametophyte without the intervention of an egg, and such a phenomenon is known as apogamy. In general, therefore, apogamy refers to the appearance of the embryos of higher plants without any sex act.