Comparative cytomorphologic aspects of the male germ cells, especially of the "Gonia".

During early development of the human testis the male germ cell first appears as primordial germ cell or gonocyte and enters the prospermatogonial stage after the twelfth week of gestation. Prospermatogonia lack glycogen particles and are connected by intercellular bridges. During the same period in the ovary the female germ cell undergoes its oogonial stage. Prospermatogonial and oogonial development have been studied histologically in three laboratory species (white mouse, Acomys caharhinus dimidiatus. golden hamster). According to the therminolgy of Hilscher et al. (1974) proposed for the rat, prospermatogonia have to be subdivided into M- T (1)- and T (2)-prospermatogonia. In the ovary they correspond to oogonia, oocytes in the prophase of meiosis and oocytes in the diplotene stage.