Differentiation of male chick embryo gonads during the last week of incubation in organ and tissue culture.

15th day chick embryo testes, were cultivated in organ and tissue culture for 5 days, in semisynthetic media. The histological examination of the cultured testes shows a noticeable retardation in development compared with normal testes at the same age. Microscopic examination of cultured testicular cells, shows two types of cells, epithelial and fibroblasts. The most remarkable result, the absence of germ cells from the tissue culture.