LXXVI BOWMAN LECTURE. 



cataract, retinitis pigmentosa, albinism, and probably 

 some of the less frequent affections, such as congenital day- 

 blindness we still find great discrepancies as to sex 

 numbers in individual families, but when large numbers 

 are taken a fairly uniform, though not extreme, pre- 

 ponderance of males. 



As the sex-inequality in this last class cannot be 

 accounted for by any obvious cause it is probably the 

 expression of some general law, and the following facts 

 seem to support this view : (1) Although more boys than 

 girls are born (about 104 boys to every 100 girls in 

 England and Wales in 1807)* the inequality is more 

 than redressed by the higher general death-rate for males 

 so that the total living population shows a deficit of 

 males (about 93 males to every 100 females in England 

 and Wales in 1907). (2) The males die in excess chiefly 

 (a) between birth and five years of age, (?;) between 

 fifteen and sixty-five ; between five and fifteen the sexes 

 die in nearly equal numbers (about fifty-one females to 

 forty-nine males). The higher mortality of males under 

 five, which alone concerns us now, is due chiefly to deaths 

 from causes classed by the Registrar-General collectively 

 as " immaturity," i. e. premature birth, congenital defects, 

 teething and congenital hydrocephalus. In 1907 out of 

 every hundred children dying from these causes under 

 five years old fifty-six were males, forty-four females. 

 (8) There appears to be a similar excess of boys over 

 girls with various " defects of development," principally 

 of the sense-organs and intelligence, such as Dr. Francis 

 Warner described in 1894 in children at the elementary 

 schools. t Dr. Warner's statistics show that if the 

 number of boys and girls examined by him had been 

 equal there would have been sixty defective boys to forty 

 defective girls in every hundred of those selected by him 

 as showing deficiencies. % 



* The data from which these and the succeeding statements are drawn 

 may be found in the Report of the Registrar-General. 



t Warner, Francis, Report of British Association. 



Since the above was written Mr. Alan Barlow has supplied me with 



