REPRODUCTIVE SYSTEM OF FREE-MARTINS 455 



The following pages comprise detailed descriptions and com- 

 parisons with normal males and females of eight free-martins, 

 viz.:— (1) f.m. T19, (2) f.m. T26, (3) f.m. T6, (4) f.ms. 13, 2, 

 and 4, (5) f.m. 12, and (6) f.m. 42. 



1. FREE-MARTIN, 7.5 CM. T 19 



The smallest free-martin which has been accessible for study, 

 T19, measures 7.5 cm. in total length. Lillie, figure 13. The 

 gonads are very small, being only 2.07 mm. long, whereas a 

 testis of its twin brother is 3.5 mm. long, and an ovary of an 

 8.5 cm. female (N4) measures 3 mm. The gonads of this free- 

 martin are lemon-shaped structures which lie close to the Wolf- 

 fian body, near its anterior end. The area of the central cross 

 section is about one-fourth of that of the testes of normal males 

 measuring 7 cm. (NIO) and 8 cm. (T19) and of the ovary of a 

 normal female, 7.3 cm. long (N8), (figs. 2, 3, and 5). 



a. Normal conditions at this stage 



In the normal male T19, twin with free-martin T19, and 

 measuring 8 cm., the sex cords, seminiferous tubules, are dis- 

 tinct, much branched, and separated from each other by con- 

 nective tissue and the cells of the interstitial gland. (Unfortu- 

 nately, the preservation of cf T19 was not made with a view to 

 histological study and the central portion of the gonad is indis- 

 tinct.) In cf NIO, 7 cm. long and preserved in strong Flemming 

 (figs. 1 and 2), the seminiferous tubules make up the larger part 

 of the testis. The outer layer, in both cases (T19 and NIO) is 

 the typical albugineal layer of connective tissue with the long 

 axis of the cells parallel to the peritoneum. The rete enters the 

 testis near the anterior end and runs posteriorly, forming the 

 core about which the seminiferous tubules radiate, figures 1 and 

 2. Most of the germ cells of the seminiferous tubules are still 

 indifferent but a very few are found in the early stages of the 

 growth period.^ 



In a normal female 8.5 cm. long (N4), the medulla is relatively 

 large in cross section. " The medullary cords have not yet begun 



3 Schoenfeld, Arch, de Biol., Tl8, 1901-02. 



