134 WALTER LAWRENCE. 



Moore ('246) has already shown that a normal breeding 

 guinea pig testis artificially retained in the abdomen loses 

 practically all its germinal epithelium within twenty days and 

 that it does not recover from this striking degeneration as long 

 as it remains in the abdomen. My own observations confirm 

 Moore's assertions that degeneration of the seminiferous tubules 

 is marked after six days, that the degenerative process is pro- 

 gressive, and that by the twentieth day the tubules contain only 

 the Sertoli syncytium within which are a few spermatogonia. 



In my series of experiments testes retained from 25-113 days 

 in the abdomen show no signs of seminiferous tubule recovery; 

 indeed degeneration is more pronounced in that the testis becomes 

 progressively smaller so that by the end of the second month the 

 whole testis is but half the diameter of the opposite or normal 

 organ. In these testes retained for two months or more in the 

 abdominal cavity the diameter of the seminiferous tubules is 

 greatly reduced and the interstitial cells occupy the greater part 

 of the intertubular spaces; there is also more or less serous 

 exudate between the tubules. The tunica albuginea is five or 

 six times as thick as that of the normal testis. 



It is apparent therefore that active degeneration of the germinal 

 epithelium begins some time before the sixth day, is most rapid 

 from the sixth to the tenth, during which time the greater part 

 of the germinal epithelium is shed; succeeding changes have to 

 do chiefly with the Sertoli cells which seem to be increased, the 

 diameter of the tubules, and the relative abundance of interstitial 

 cells. The rapidity of the transformation seems to be quite 

 constant for all animals studied. 



Vas Deferens Ligation of Abdominal Testes. Seminiferous 

 tubule degeneration, as pointed out above, is of a varied char- 

 acter; some cells are thrown out into the lumen, some apparently 

 undergo solution in situ, the autolyzed products being absorbed 

 directly into the blood stream. The question arose in reference 

 to this degeneration, whether a part of the fragmenting cells and 

 general debris in the lumen of the tubules were carried into the 

 epididymis and eliminated from the body through the genital 

 passages, or whether it was wholly or partially absorbed into 

 the blood stream from the testis. To demonstrate just what 



