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 



1856-60 23 . 3 



1866-70 32.8 



1876-80 45 . i 



1886-90 59 . 2 



1896-90 69 . 2 



1906-10 86 . 9 



1911 92.6 



1912 94.0 



1913 99-4 



