PAPERS ON MEDICINE AND PUBLIC HEALTH 311 



DISEASES AND FATE OF TWINS 

 Dr. I. A. Abt, Chicago 



It is with the modern biological, rather than with an 

 anthropological, study of twins that the present paper 

 is concerned. Grassl expresses the opinion that multiple 

 pregnancies are neither atavistic nor the result of varia- 

 tion, but simply indicate an excess of the natural or 

 usual fertility. 



A. Orgler recorded some observations on twins from 

 his examination of twenty-six pairs. The weight was 

 the same in only five pairs. The difference in weight 

 was more marked when the twins were of different sex. 

 They usually increased in weight at the same rate, 

 though frequently one continued to be heavier than the 

 other for a considerable time, unless one or the other fell 

 ill. He also observed that if both twins fell ill, one of 

 them usually lost more markedly in weight than the 

 other, and when they regained health, both increased in 

 weight at the same rate, though the original dispropor- 

 tion continued for some time. 



In a number of cases the heavier child is more resist- 

 ant and becomes less severely ill when attacked than the 

 lighter one. In a number of cases this does not hold. 

 Frequently there is a difference in the length of the chil- 

 dren at birth. While many of them seem to increase at 

 the same rate, in a certain number the increase in length 

 occurs at different rates, so that the one shorter at birth 

 may reach the height of the longer one or even over- 

 take him. 



The average weight of twins is approximately eqjui], 

 to the weight of a single newborn. The average wei^rc 

 of uni-sexual twins was 3960 grams, though the female 

 pair weighed 840 grams less than the male. The average 

 weight of the male pairs was 4380 grams, of female pairs 

 3540 grams, and the average weight of one twin was 

 1980 grams, though there was a difference in the weight 

 of the sexes. Thus, boys weighed on the average 2190 

 grams, girls 1770 grams. 



Concerning the height of newborn twins, it may be 

 noted according to the statistics of N. Miller that the 



