28 THE FITNESS OF THE ENVIRONMENT 



sunshine to the waste heat of the animal 

 body. 1 



B 



ORGANIC CHEMISTRY 



Independent alike of general biology and 

 of the science of metabolism there has grown 

 up still another department of natural sci- 

 ence, organic chemistry, which contributes 

 very materially to the description and com- 

 prehension of living things. During a large 

 part of the nineteenth century the efforts of 

 chemists were mainly directed to the cultiva- 

 tion of this subject, which seeks to describe 

 the molecular constitution of all the com- 

 pounds of carbon, including nearly all the 

 individual substances which make up animals 

 and plants. Gradually, as organic chemis- 

 try has progressed, very complete descrip- 

 tions of the atomic groupings within the 

 molecules of fats, 2 carbohydrates, 3 and pro- 



1 Here, as in so many other cases, it is not the conservation 

 of matter and energy, but the conservation of matter and the 

 degradation of energy which are important. For an exten- 

 sive development of this important difference see B. Brunhes, 

 "La Degradation de l'Energie." Paris, 1909. 



2 Chevreul, " Recherches Chimiques sur les Corps Gras." 

 Paris, 1823. 



3 E. Fischer, " Untersuchungen liber Kohlenhydrate und 

 Fermente." Berlin, 1909. 



