488 DR MATTHEWS DUNCAN ON THE VARIATIONS OF THE FERTILITY 



2. That initial fecundity is very high from 20 to 34 years of age. 



3. That the climax of initial fecundity is probably about the age of 25 years. 



At this point my present inquiry is closed. I know of no other way of ad- 

 vancing our knowledge of this subject, than by the collection and analysis of 

 statistics. The only very good quarry for such materials that I know of is the 

 Scottish registers for 1855. The tables adduced might be improved by going over 

 a larger field, and increasing the numbers analysed. But I do not see how the 

 matter in the registers could be turned to more account, without encroaching on 

 another topic which is at the same time closely connected with that under discus- 

 sion, — viz., the fertility of marriage. Or, as marriage is scarcely admissible as a 

 term in physiology, I should give this subject the title of ' sustained fecundity,' 

 the degrees of fertility which women of different ages, beginning to live with men, 

 continue to exhibit during the child-bearing period of life. In the meantime I 

 shall summarily state, that, so far as I have advanced in this new topic, the evi- 

 dence gained shows that, speaking generally, young women after the outset of 

 child-bearing continue to exhibit a fecundity greater than is sustained by those 

 married when comparatively elderly. The fourteenth table exhibits some of these 

 results. It reads as follows : — Wives of from 20 to 24 years of age exhibit in the 

 fifth year of marriage a comparative fecundity of 1 in 3-0 ; wives of from 25 to 

 29 years of age exhibit in the fifth year of marriage a comparative fecundity 

 of 1 in 14-5 ; and so on. The table shows that at the fifth, the tenth, and the 

 fifteenth years of marriage, the mass of women youngest married continue to 

 show the greatest fecundity. The mass of younger women not only are more 

 fecund at the outset of child-bearing, but after that time is past, they continue 

 more fecund than older women who have been married the same number of years. 



TABLE XIV.* — Showing the Fecundity op Wives in Edinburgh and Glasgow, 



AFTER THREE DIFFERENT PERIODS OF CONTINUANCE IN THE MARRIED StATE. 



Age of Wives, 



20-24 



25-29 



30-34 



35-39 



40-44 



Fertility in Fifth Year of Marriage 



Fertility in Tenth Year of Marriage, 



Fertility in Fifteenth Year of Marriage, .... 



3-0 



14-5 

 40 



59-9 



23-2 



6-5 



202-4 



955 



44-3 



698-2 



1 



404-9 

 3400 



I have made various other inquiries with a view to throw light on the topic of 

 this paper. They refer to variations in sex, size, and weight of newly-born children 



* This Tahle is not prepared so as to show anything- more than is described in the text. Espe- 

 cially the figures in one horizontal line should not be compared with those in another horizontal 

 line. To permit this, the table requires large corrections for deaths. 



