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RADIATION BIOLOGY 



mice used, or to other variables in experimental conditions, for it can be 

 seen from Table 12-2 that the data of Hertwig show appreciable incidences 



Table 12-2. Incidence of Permanent Sterility in Male Mice Exposed to 



Various Doses of X Radiation 



a Unpublished data of W. L. Russell, Josephine S. Gower, Gloria J. Jasny, and J. C. 

 Kile. 



6 Died less than twelve weeks after mating and tested against only one female each. 

 c Tested against only one female each. 



of permanent sterility with doses of 1000 r and below, while those of 

 Russell et at. show no difference from the controls even with 1000 r. 



Up to the dose level above which breeding experiments become imprac- 

 ticable, no effects on the viability or motility of mature sperm have been 

 observed. In electrically induced ejaculations from guinea pigs, Strand- 

 skov (1932) found motile sperm up to four weeks following exposure to 

 2592 r of X rays. Snell (1933b) performed a bilateral vasa efferentia 

 ligation on six mice and irradiated three of them with 800 r of X rays. 

 There was no difference between the irradiated and nonirradiated animals 

 in length of survival of motile sperm in the epididymides. 



The testis was one of the first organs studied histologically for the 

 effects of X rays and has since been the object of numerous investigations. 

 The references cited, particularly Schinz and Slotopolski (1925) and 

 Glucksmann (1947), may be used as an introduction to the voluminous 

 literature which can be only briefly summarized here. Hertwig (1938b) 

 and Schaefer (1939) have studied the subject with particular regard to 

 its bearing on genetic problems. There is now almost unanimous agree- 

 ment that spermatocytes, spermatids, and sperm, along with Sertoli cells 



