REPRODUCTIVE SYSTEM OF FREE-MARTINS 471 



in the 16.75 cm. male. Numerous, much convoluted vasa 

 efferentia lead from the rete into the coiled vas epididymis which 

 in turn opens into the Wolffian duct. The Mtillerian duct has 

 long since atrophied. 



In the case of the females, there were sectioned the left ovary 

 and ducts of a 20 cm. 9 N24 and the left ovary and ducts of a 

 23 cm. 9 N25. A dissection was made of the reproductive sys- 

 tem of a third female, measuring about 20 cm. The sectioned 

 ovary of the 20 cm. $ was 4.440 mm. long. That of the 23 cm. 

 9 measured 6.830 mm. The condition of the ovaries is almost 

 the same in these two cases. The medulla is relatively larger 

 in the younger specimen. In N25, figure 11, it is composed 

 mainly of fibrous stroma and contains fewer medullary cords 

 than does the medulla of the smaller female. 'Nests' of cells, 

 primary follicles, first found in the cortex in the 17 cm. 9 N23, 

 are more numerous in each succeeding stage. The individual 

 cords of Pfliiger are surrounded by wide sheaths of stroma, but 

 in this large amount of interstitial material, no interstitial cells 

 have been identified with certainty. Most of the cells are the 

 long slender spindle shaped cells typical of embryonic connec- 

 tive tissue. In the smaller female, most of the germ cells which 

 are found in the growth period are in Schoenfeld's early stages, 

 though a few have reached as advanced a stage as i. In the 

 23 cm. 9 they are found in these same stages, the majority of 



Fig. 10 Cross section through Wolffian body and middle of testis of 24 cm. 

 c? bos embryo, T4. 1, superficial epithelium; 2, blood vessels in tunica vas- 

 culosa; 3, rete; 4, interstitial material, including connective tissue stroma 

 and interstitial cells; 5, seminiferous tubules; 6, albuginea; 7, degenerating 

 Wolffian tubule; 8, Wolffian duct. X 15. 



Fig. 11 Cross section through Wolffian body and middle of ovary of 23 cm. 

 9 Bos embryo, N25. Note that the rete does not extend as far as the 

 middle of the ovary. 1, tubule of epoophoron; 2, degenerating Wolffian tubule; 

 3, MiiUerian duct; 4, primary follicle formed at inner end of cord of Pfliiger; 5, 

 primary albuginea; 6, medullary cords; 7, cords of Pfliiger; 8, germinal epithelium 

 (scarcely distinguishable from cord of Pfliiger) ; 9, beginning of ovarian albuginea. 

 X 22. 



Fig. 12 Cross section of gonad and Wolffian body of 20 cm. free-martin 

 T13, and entrance of rete into gonad. 1, degenerating Wolffian tubule; 2, rete; 

 8, sex cord region (no differentiation), 4, rudiment of MiiUerian duct; 5, fold 

 of peritoneum overhanging gonad. X 28. 



