486 DR MATTHEWS DUNCAN ON THE VARIATIONS OF THE FERTILITY 



ages of 20 and 24 inclusive, and a gradual declension from that time on either 

 side as age diminishes or increases. 



TABLE X. — Showing the Initial Fecundity of Women of Different Ages within 



THE First Two Years of Marriage. 



Ages of Wives newly ) 

 Married, . . . j 



15-19 



20-24 



25-29 



30-34 



35-39 



40-4445-49 



50-54 



55-59 



60-64 



65-69 



Total. 



No. of Wives newly ) 

 Married, ... J 



No. of Wives Mothers \ 

 within two years of >- 

 Marriage, . . . j 



Proportion of latter ) 

 to former is 1 in / 



700 

 306 

 2-3 



1835 



1661 



M 



1120 

 849 

 13 



402 

 253 

 1-5 



205 

 84 

 2-4 



110 



17 



6-4 



46 



2 



23-0 



20 



6 



2 



1 



4447 



3172 



1-4 



Percentage, .... 



43-71 



90-51 



75-80 



62-93 



40-97 



15-45 



4-35 



... 



... 



... 



... 



71-33 



The two following tables (XI. and XII.) show that on the side of the women 

 younger than 20 years, initial fecundity steadily decreases with age. In regard, 

 however, to these young wives, it may be objected that there is a source of error 

 from immaturity which is certainly very trifling after the age of 20 is reached. 

 And the objection is, theoretically at least, quite just, for it is absurd to attempt 

 to measure the fecundity of women who have not become sexually mature, and 

 the admixture of immature with mature is a source of error, important, directly 

 according to its amount. It is unsatisfactory merely to allege in answer, that 

 immature girls are not likely to be found among young wives in such numbers as 

 to form a source of great error. I have therefore taken the following means to 

 ensure that this source of error be completely excluded. 



TABLE XI. — Showing the Initial Fecunditv of Women under 20 Years of Age 



IN THE First Year of Marriage. 



1 

 Ages of Wives newly Mai-ried,^ 



16 



17 



18 



19 



No, of Wives newly Married, 



No. of Wives Mothers within first year of Marriage, 



Proportion of latter to former is 1 in 



Proportion after correction for Immaturity, is 1 in 



43 



2 



21-5 



15-5 



108 



7 



15-4 



12-8 



225 

 31 



7-2 

 7-0 



314 



56 



5-6 



5-4 



Percentage, 



6-45 



7-77 



14-70 



18-30 





