CYTOLOGICAL STUDY ON THE GONADAL DEVELOPMENT OF F1 HYBRID PRODUCED BY CROSSING CARASSIUS AURATUS L.(♀) WITH CYPRINUS CARPIO(♂)

Results of the present study are summarized as: 1). The gonad of the F1 female individuals occurred in two forms: one is completely fertile (44.3% of the stock), the other is abnormally developed (55.7% of the stock). In the latter condition, the ovari es are hermaphroditic, being composed of oocyte and spermacyte; 2). The gonad of F1 male individuals appeared in three states: the first is completely fertile (4.67% of the total), and the entire course of development (from spermatogonia to spermatozoa) can be completed endogenously under pond enviroment. The second (about 61.7%) is par tially developed, with some of the spermatoblasts forming spermatiozoa. The third, which consists of hermaphrodite (20.63%) and non-hermaphrodite (13.0%), cannot pro duce mature spermatozoa and is completely sterile.Due to the fact that some of the F1 male hybrids are completely fertile, F2 as well as F3 generation was also obtained.