THE SCOPE OF BIOLOGY O 



GENETICS and EMBRYOLOGY; and the origin and develop- 

 ment of species, ORGANIC EVOLUTION, are other wide fields, 

 sciences in themselves, which must be approached from both 

 the structural and functional aspect if any real advance is 

 to be made toward a comprehensive appreciation of life. 



(Fig. 1.) 



Thus, just as the various physical sciences have expanded 

 and become specialized until they are beyond the grasp of 

 a single man, so biology and its subdivisions, or the BIO- 

 LOGICAL SCIENCES, are now distributed among many special- 

 ists. Although specialization results in a narrowing and 

 isolating of the fields of study, as deeper levels of investiga- 

 tion have been reached in all the sciences there has been a 

 tendency for the basic phenomena to meet on the common 

 ground of the fundamental sciences, physics and chemistry 

 -for in the last analysis the biologist must assume as a 

 working hypothesis that the properties of protoplasm are the 

 resultant of the properties and interrelationships of the 

 chemical elements which compose it. "In one direction, 

 supported by chemistry and physics, biology becomes bio- 

 chemistry and biophysics. In a contrary direction it forms 

 a connection with the psychical sciences which relate to 

 human nature, with psychology and sociology, with ethics 

 and religion." 



