

DEVELOPING 

 SEMINIFEROUS 

 TUBULES 



OVARIAL SAC 



Fig. 350. Sex gland differentiation. (A) Transverse section through early genital 

 rudiment on media! aspect of mesonephric kidney in the 10 mm. pig embryo. (B) 

 Transverse section through early sex gland of the chick about middle of sixth day of 

 incubation showing ingression of sex cord of first proliferation. Observe primordial germ 

 cells in germinal epithelium. Compare with fig. 345G. (Redrawn from Swift, 1915, Am. 

 J. Anat., 18.) (C) Transverse section through sex gland rudiment of human embryo 

 11 mm. greatest length. (Redrawn and slightly modified from Felix, 1912, Chap. 19, in 

 Human Embryology, vol. II, by F. Keibel and F. P. Mall, Lippincott, Philadelphia.) 

 (D) Transverse section through testis of human embryo 70 mm. head-foot length. 

 (Redrawn from Felix, 1912. For reference see C above.) (E) Section through human 

 testis of embryo 70 mm. head-foot length, showing connection between testicular cords 

 (developing seminiferous tubules) and developing rete tubules. (Redrawn from Felix, 

 1912, reference same as in C, above.) (F) Transverse section through testis of seventh 

 month human embryo showing developing seminiferous tubules. (Redrawn from Felix, 



(Continued on facing page.) 



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