THE STRUCTURE OF FREE-MARTIN GONADS 



75 



penetrates to the posterior end of the medullary cord region, but 

 not at as early a stage as the rete testis. It retains its primitive 

 position at the hilus of the ovary during its further development 

 (fig. 3). On the other hand, the rete testis penetrates at an 



Fig. 4 Transverse section through the middle of the testis of a 20-cm. male 

 bos foetus, N 21. bv, blood-vessel in tunica vasculosa; r, rete testis (note its 

 central position); s, seminiferous tubules (note that the seminiferous tubules 

 are more convoluted near the periphery of the testis); st, tubuli recti; ta, tunica 

 albuginea; tv, tunica vasculosa; wd, Wolffian duct. X 33. 



early stage to the posterior tip of the testis, to form an axis from 

 which the seminiferous tubules radiate in all directions (fig. 4). 

 During the early development of the testis the rete lies between 

 the mesentery and the sex-cord region, and as the seminiferous 

 tubules begin to grow, they extend around the sides of the rete 

 until they meet, making the rete appear to be in the center of a 

 round gland; that is, seminiferous tubules grow around the 



