BIOLOGY: E. HUNTINGTON 
131 
It appears as if climatic environment were able to cause changes in pig- 
mentation and bodily form more easily than in the more direct physio- 
logical conditions which determine the relation of the organism to tem- 
perature. 
There is probably, however, a slight difference in races, as appears 
from a comparison of the deaths among colored and white people in 
the twelve American cities where colored people are most numerous. 
Unfortunately the figures for the two races have been published sep- 
arately only since 1912, and only the years 1912-1914 are available. 
The results are given in table 4. 
TABLE 4 
Optimum Temperature among White and Colored People During the Years 
1912-1914 on the Basis of the Death Rate 
PLACE WHITE COL'D PLACE WHITE COL'd PLACE WHITE COL'd 
I. Northern cities II. Central cities III. Southern cities 
New York... 68. 5 71.4 Baltimore. . ..60.4 69.2 Atlanta 59.2 72.4* 
Chicago 65 . 5 69 . 4 Louisville ... 68 . 0 74 . 5 Birmingham.73 .3 72 . 2 
Philadelphia. 68.0 74.0 St. Louis. .. .70.8 74.9 Memphis. .. .68.2 76.8 
Washington . 65 . 3 69 . 2 Richmond ... 66 . 4 66 . 4 
Average.. 67. 3 71.8 
Average. .66.6 72.0 Average .-. 66 . 8 72.0 
Weighted Grand Average: White 67.5, Colored 71.6 
* This figure is doubtful. A much more pronounced minimum of deaths occurred at a 
temperature of 44°. This apparently means that a good many colored people come to Atlanta 
in the summer and go away in the winter. 
Because of peculiar weather conditions, epidemics, or other causes 
the optimum during the years 1912-1914 was 2° or 3° higher than dur- 
ing the longer series of years indicated in a preceding table. Such dif- 
ferences are inevitable and need not here concern us. The important 
point of the present table is that as a rule the negroes seem to be at 
their best at a temperature 4° or 5° higher than that which is best for 
white people. This, however, is insignificant compared with the dif- 
ference of 40° between the mean temperature of the Baltic home in 
which the white race probably developed and the African home of the 
negroes. Moreover, the average optimum temperature in northern, 
middle, and southern cities is almost identical. There is not the slight- 
est hint that either the whites or the colored people by residing in the 
north or the south have become adjusted to a particular temperature. 
So far as these facts go, therefore, they suggest that man's adaptation 
to temperature is so deep seated and of such remote origin that it changes 
very slowly. Untold thousands of years of the contrasted environments 
of northwestern Europe and central Africa appear to have produced a 
