BOWMAN LECTURE. LXXVJ1 



Archibald Grairod* states that the rare heritable con- 

 ditions, alkaptonuria, cystinnria and pentosuria are all 

 more frequent in males than females. In 157 subjects of 

 these three diseases he finds no less than 113 males. 



Now it is not a little remarkable, as regards the third 

 group of eye diseases just mentioned, that in retinitis pig- 

 mentosa (1381 cases) and lamellar cataract (1793 cases), 

 62 per cent, of those affected are male and 38 female ; 

 whilst in other forms of congenital cataract (335 cases) 

 and in albinism (upwards of 1000 cases) the proportions 

 are not very different about 55 per cent, males and 45 

 per cent, female. In day-blindness there is a consider- 

 able excess of males. 



It is said also that there is a marked excess of males 

 over females amongst deaf-mutes. 



I feel sure that stores of information as to the relative 

 liability of the sexes to hereditary disease must exist. 

 But meanwhile the few facts now brought forward favour 

 the view that, in man, the male is on the Avhole more 

 liable than the female to many innate defects and diseases, 

 and perhaps especially to such as affect the organs of 

 sense and intelligence. 



It is extremely important to know whether the inheri- 

 tance of an imperfection influences the longevity of the 

 affected who survive ; either by the direct effect of the 

 disease upon vitality as in diabetes or haemophilia, or by 

 some figures from the Education Office, which, although probably needing 

 correction in certain particulars, appear to point in the same direction. 

 These figures are taken from the Statistics of Public Education, 1906-7-8, 

 and refer to the number of children between the ages of five and sixteen 

 attending schools for the defective and epileptic in England. The 

 average number of children attending about 160 such schools in each of 

 the three years mentioned was 10,464, of whom 6019 were boys and 4445 

 girls. The numbers are vitiated to some extent by the facts that (a) 

 they include a certain number with physical rather than mental defects, 

 and (6) boys tend to leave the schools at an earlier age than girls ; but 

 these two sources of error may not improbably tend to cancel each 

 other, and in any case would not be likely to account for nearly all the 

 difference between 57 and 43 per cent, shown by the above numbers. 

 * Archibald Garrod, Inborn Errors of Metabolism, 1909, p. 20. 



