104 LEONELL C. STRONG 



Tabulation 



Males 299 negative : 20 reactions ±2.92 or 6.27% ± 0.91 

 Females 353 negative : 15 reactions ±2.55 or 4.07% ± 0.70 

 Difference 2.20% ± 1.15 



The difference is thus 1.91 times the probable error 



There is still no significant difference between the sexes, 

 although the males are slightly more susceptible. The curves 

 for the inoculation are quite different from the analogous 

 curves for the second inoculation, although not significantly so, 

 as will be discussed later. Figure 19 (p. 103) is a composite for 

 figures 17 and 18. 



Tabulation 



Total castrated males 607 negatives : 36 reactions ±3.93 or 5.60% ± 0.61 

 Total spayed females 672 negatives : 27 reactions ±3.43 or 3.86% ± 0.48 



Difference 1.74% ± 0.77 



The difference is thus 2.26 times the probable error 



The male curve is still slightly above that for the females, 

 but not significantly higher. The initial susceptibility of the 

 sexes is approximately equal. The females are, however, able 

 to resist the action of the tumor cell better than the males, and 

 almost entirely eliminate it within the six-week period (one spayed 

 female, however, continued to grow the tumor progressively). 

 The castrated males, on the other hand, have a harder struggle. 

 They fail to eliminate some but not all of the transplantable 

 tumors, since a few individuals continue to grow the tissue mass 

 progressively. 



Comparing the castrated males (first inoculation only) with 

 the normal males, we obtain an entirely different type of curve. 

 The normal male curve is probably significantly higher than the 

 castrated one. (The last three points are, however, not different ; 

 figure 20, heavy solid fines.) 



Tabulation 



Normal males 313 negatives : 46 reactions ±4.27 or 12.81% ± 1.19 

 Castrated males 308 negatives : 16 reactions ±2.64 or 4.93% ± 0.82 



Difference 7.88% ± 1.44 



The difference is thus 5.48 times the probable error 



