376 THE TREND OF THE RACE 
Australia. In the more advanced ages the expected duration of 
life has shown a smaller amount of increase, but in a number of 
countries even the man of eighty may count on living a little 
longer than he would a few decades ago. 
The increase in the degenerative diseases of later life in the 
United States is probably due, to a considerable extent, to the 
increase of our foreign stocks which show a strong tendency 
to segregate in cities where they live under conditions which 
frequently dispose them to an early break down. It is a debatable 
question, especially in view of the varying categories of the 
diagnosis of disease, whether degenerative diseases are on the 
increase in the civilized world, and it is further a matter of un- 
certainty how far our industrial development and increasing 
urban life may tend to accelerate the development of these 
afflictions. 
The most discussed problem in relation to the increase of 
degenerative diseases is that of the alleged increase of cancer. 
The problem is of particular importance since cancer ranks very 
high among the causes of death in adults, especially those of 
over 45 years of age. Many medical writers have become con- 
vinced that cancer is on the increase. Certainly the mortality 
statistics of most civilized countries attribute an ever increasing 
proportion of deaths to this cause. Taking the statistics of cancer 
mortality for Massachusetts, for instance, we find the following: 
Proportions of Deaths from Cancer in Massachusetts 
Years Cancer Death Rate per 100,000 
TOSO-OOsk eo i7ah oe Sadewes 23.3 
1806-70; 505 sve Gee ae eee 32.8 
TS 70-802 ase cap anne ia Mamas 45.1 
1880—-00-2 seis eusagusesswdens 59.2 
T8060-00s etic s al enka es 69.2 
LQOOHIOs0. Tp ae wish aoe BES Pees 86.9 
TOUT esti sa ceteqadieea ads 92.6 
TODO he Giese Acta teays 94.0 
IQT3 ec anes dee Wee yey Hee a 99.4 
