| Abstract: | The early development of the gonads, and the ontogenesis of the rete testis and tubuli seminiferi recti in the chicken (Gallus domesticus) The primordium of the gonads can be discerned in the 4-day chick embryo by the elevation of the celomic epithelium to form germinal epithelium, and by the arrival of the primordial germ cells. Already in the 4½ day chick embryo there appears on the left side of the body, as a result of the first proliferation of the germinal epithelium, a subepithelial mesenchymelike cell conglomeration, which has been erroneously labelled in the literature a “urogenital union”. In contrast to the opinion expressed in the literature such a union does not appear until the 10th day, when the mesenchymal cells change to forerunners of rete cells which after hatching differentiate into rete-epithelial cells. The rete testis consists of intra and extratesticular transverse cisterns and of an intercalated and partically subdivided longitudinal cistern. The tubuli seminiferi contori end on the intracapsular lingitudinal cisterns either directly, or indirectly by intercalated tubuli siminiferi recti or intratesticular transverse cisterns. |
