WHAT IS PHYSICAL LIFE 



son's disease I have kept for a number of 

 years from succumbing to it, by daily 

 doses of extracts of the adrenals of sheep. 

 Here, therefore, is another adaptation, 

 which would make all the other number- 

 less adaptations useless if it alone were 

 wanting. 



In the foregoing brief review we have 

 merely given examples, out of any num- 

 ber of others, of adaptations in the living 

 body, by far the most of which, if they 

 failed to fit perfectly, would involve 

 death. No satisfactory account of the ori- 

 gin of any of them has yet been given. On 

 this one subject of adaptation the words 

 of Professor Kellogg may well apply, 

 " We are ignorant, terribly, immensely 

 ignorant." * But he sensibly adds, " Our 

 work is to learn, to observe, to experiment, 

 to tabulate, to induce, to deduce." They 

 must all occur according to natural laws, 



* Darwinism To-day, p. 337. 

 150 



