heterogenesis

n. [ Hetero- + genesis. ] 1. (Biol.) Spontaneous generation, so called. [ 1913 Webster ]

2. (Biol.) That method of reproduction in which the successive generations differ from each other, the parent organism producing offspring different in habit and structure from itself, the original form, however, reappearing after one or more generations; -- opposed to homogenesis, or gamogenesis. [ 1913 Webster ]