The Effect of Temperature on Nuclear Differentiation in Microspore Development

Abstract

With one text figure and plate 150 "HEREDITY is effected by the transmission of a nuclear preformation which, in the course of development, finds expression in a process of cytoplasmic epigenesis" (Wilson, 1925).The evidence from genetic and cytological investigations has proven conclusively that nuclear preformation is dependent upon the genic constitution of the chromosomes.The mechanism of expression in cytoplasmic epigenesis is more obscure.The problem is difficult because it is not subject to direct attack.