298 THE TREND OF THE RACE 
The lengths of the same series of babies were found to be 
as follows: 
Birth Order | I 2 | 3-4 | 5-6 | 7-8 | 9-10 |11andover|Mean Length 
BOYSija- ues xs Meee os 20.62]20.82|20.80/20.95|20.98]20.99| 21.14 20.81 
Gitlin £503 deeices 20.27}/20.33]20.51]20.43/20.36/20.41| 20.73 20.38 
These sets of tables,—and there is considerable additional 
evidence to the same effect,—indicate that the first born infants 
of both sexes are lighter in weight and shorter than the second 
born, and that there is a general increase according to order of 
birth until near the close of the child-bearing period. The reason 
for the relatively small size and weight of the first born may lie 
in the fact that the mothers are, on the average, young, and also 
in the circumstance that their organization is not so well adapted 
to child bearing as it becomes after one or more births. It is well 
known that the first birth is usually the most difficult. There is a 
relatively larger number of stillbirths among the first born. 
Taking the records of 48,843 births among the professional and 
upper classes, Ansell found the proportions of stillbirths distrib- 
uted as follows: 
Order of Birth I 2 3 4-6 | 7 and over 
Still births per 1,000 born alive. ......... 4o | 20 | 15.5 | 17.4 | 20.9 
According to Ansell there is a greater mortality among the 
first born in the first year of life. From the records of the 48,843 
births just mentioned he obtains the following data: 
Order of Birth I 2 3 4-6 | 7 and over 
Deaths in rst year per 1,000 living births .| 82.2 | 70 69 | 78.3 97-4 
Additional evidence in the same direction is furnished by 
Pearson from the records of the artisan classes from several 
