n6 THE MAIN CURRENTS OF ZOOLOGY 



organic evolution, the truth of which is so clearly 

 evidenced by the facts of comparative anatomy, of 

 embryology and of paleontology. Philosophical 

 interpretations of development, of heredity, and of 

 other zoological generalizations, also come under this 

 division of zoology. 



Miscellaneous Divisions. Zoology has been 

 broadened and enriched by the cultivation of especial 

 lines of interest and this has led to an arbitrary sub- 

 division of some of the larger provinces. The position 

 of some of these subjects is not clearly defined and 

 they owe their prominence to particular interest in 

 their applications. Others of the miscellaneous group 

 are clearly offshoots from the larger divisions. 



Eugenics. The subject of Eugenics (a subdivision 

 of Genetics) commands at present a large place. 

 This scientific study of the conditions that may im- 

 prove or impair the racial qualities is properly under- 

 taken only on a broad knowledge of biology and, 

 especially, of zoology. As previously stated it was 

 especially fostered by Francis Galton. 



Protozoology. In reference to unicellular organ- 

 isms, a department of protozoology has been created 

 with especial reference to pathogenic protozoa. But, 

 quite outside the question of disease-producing 



