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The Journal of Heredity 



about whom we have gathered com- 

 plete information has hardly more 

 than replaced itself. There were 126 

 men in this decade whose total number 

 of children to date, living and dead, 

 were reported. There were nineteen 

 single men. The married men had 

 been married an average of 22.7 years 

 when the information was collected. 

 This parental group of 271 persons 

 (husbands, wives, and single men) had 

 279 surviving children. The latter ex- 

 ceeded the former by three per cent. 

 The average age of the children is not 

 known, but it is probably considerably 

 less than the above average duration 

 of the married period. That is, the 

 mean age of the children is doubtless 

 less than twenty-three years. The 

 slight excess (3 per cent.) in the num- 

 ber of children above the parental 

 group will undoubtedly be lowered or 

 obliterated by the time the average 

 age reaches twenty-three years. 



If only those families (70 in num- 

 ber) are considered in which future 

 child bearing is improbable or impos- 

 sible, the surviving children (161) ex- 

 ceed the parental group (husbands, 

 wives, and a proportionate number of 

 single men) by only 6.6 per cent. The 

 average duration of married life in 

 these cases was 25.3 years. 



The ages of the fifteen women gradu- 

 ates of the decade 1890-1899 show that 

 their families will doubtless not in- 

 crease. All but one (43 years old) 

 have reached or passed their forty- 

 fifth year. There are only twenty- 

 two surviving children, scarcely half 

 the number (45) of the parental group 

 (husbands, wives, and single women). 



Conclusion 



I believe the facts justify the fol- 

 lowing conclusions. (1) The selected 

 group of graduates I have studied will 

 raise to maturity only about enough 

 children to replace itself. (2) Could 

 complete data have been collected for 

 all the graduates from 1870-1899, it 

 would probably have been found that 

 this aggregation has not replaced itself. 

 It will be recalled that about twenty- 

 five per cent of the alumni are dead. 

 This means that the survivors, to whose 

 families almost exclusively our facts 

 apply, were longer-lived, on the whole, 

 than their deceased colleagues. The 

 longer-lived people have the larger 

 families. Hence the group of alumni 

 we have studied was doubtless some- 

 what more fecund, in proportion to its 

 size, than the whole alumni body. 

 Therefore, if the former scarcely more 

 than replaced itself, the latter probably 

 did not.* 



The writer does not imply that 

 Allegheny College is in any way 

 unique in this respect. Low birth 

 rates seem to be characteristic, as has 

 been mentioned, of college graduates 

 and the "higher" classes of society in 

 general. The showing of the Allegheny 

 College alumni is better than that of 

 graduates of Wellesley, Mount Holy- 

 oke, Vassar, Harvard, Yale, and Syra- 

 cuse. The writer is inclined to believe 

 that the pleasant and wholesome social 

 relationships, fostered by the college 

 authorities, between men and women 

 students at Allegheny, favors matri- 

 mony. 



*The following suggestion was received from Dr. Sewall Wright of Washington, D. C, 

 after this article went to press: 



Lt is obvious that the parental group under consideration includes not only the college 

 graduates, but also a part of the general population, namely, the wives and husbands of 

 these graduates. Hence, in addition to including in the parental group the unmarried 

 graduates, a certain number of unmarried persons from that section of the population into 

 which the graduates married should have been added to the parental group. The writer 

 knows of no way in which the appropriate number of such single persons from the general 

 population could be comiputed. However, it is clear for the above reason that the parental 

 group cited in this paper is smaller than it should be. Therefore, it seems likely that the 

 families of Allegheny graduates have fallen even farther short of replacing their section 

 of the population than is indicated in this article. 



