OF ATTRIBUTES IN STATISTICS. 



315 



TABLE IX. Showing the Association between Imbecility or Idiocy and Deaf-mutism 

 for both Sexes and successive Age Groups ; and the proportion per 100,000 of 

 Imtaciles and Deaf-mutes. 



nutrition.* In the case of Census defects (Tables VIII. and IX.), the proportion per 

 100,000 living at all ages is less for females in blindness, deaf-mutism, and 

 imbecility, but greater for females in the case of general mental derangement. 

 Comparing the separate age groups the proportion per 100,000 living at each age is 

 least for females in every case at age groups under twenty-five. In the older age 

 groups, on the other hand, in the cases of mental derangement and imbecility, the 

 females show the greater proportion of defectives. 



Thus at first sight it would appear that the female, though at first a greatly 

 superior animal to the male, was liable to break down mentally at a much more rapid 

 rate and at an earlier age. This, however, would probably be a fallacious conclusion ; 

 it is pointed out in the Census Report for 1881 that the death-rate for male 

 lunatics is known to be very much higher than for female lunatics almost half as 

 high again in fact.t Hence the greater proportion per 1000 living at the later age 

 groups may, either entirely or to a large extent, be simply due to accumulation. 

 There is apparently no evidence that the case-rate is greater for females at the 

 higher age groups. Thus, so far as we can say at present, the female may remain 

 the less defective animal throughout life. 



69. Summarising the general conclusions, I have shown good ground for accepting 

 as general laws that females are more highly associated than males, and that 



* Cf. Table VI., p. 54, for a comparison in each separate Standard. 



t General Iteport for 1881, pp. 66-67 : " According to the returns of the Lunacy Commissioners from 

 1872 to 1881 inclusively, the mean annual death-rate among the registered male insane was 1T94 per 

 cent, of the average daily number on the register, while the death-rate of the females was 8' 13 per cent. 

 The recovery rate of the males was 10'50 per cent., and that of the females 11-59 per cent." 



2 82 



