DEVELOPMENT OF ZOOLOGY 521 



Species. His work greatly stimulated systematic studies and 

 laid the foundation for work in other iields of zoology. 



Buffon (i 707-1 788), in his Natural History, Cuvier (1769- 

 1832) in his "Animal Kingdom," Lamarck (i 774-1829), von 

 Siebold (1804-1885) and many later naturalists have worked 

 to perfect our system of classification of animals. 



517. Anatomy and its Divisions. — We have seen that Galen 

 studied the anatomy of lower mammals to throw light on 

 medicine. His accounts became the accepted rule for centuries. 

 Vesalius (15 14-15 64) a physician, born in Brussels, made elabo- 

 rate studies of the anatomy of the human body as well as of 

 many other animals. He published a great work on the ' ' Struc- 

 ture of the Human Body," in which he denied many of the views 

 held previously. His discoveries were illustrated by many 

 most effective figures and plates. Both because of the scope of 

 his work and of this investigative spirit Vesalius laid the founda- 

 tion of modern scientific Biology. It was not so much that all 

 his conclusions were correct. He did what was much better ; he 

 made it possible for his successors to criticise and add to his 

 work by following his own attitude. This makes progress. 



Prom the study of the habits and exterior of animals, and 

 the study of human anatomy, students would naturally pass to 

 a study of internal structures. As time passed and details of 

 structure accumulated, two new lines of study would be devel- 

 oped : a closer comparison of the structure of different organisms, 

 and, second, the study of smaller and smaller structures. The 

 former is called Comparative Anatomy, and the latter Histology 

 and Cytology. 



As in all other branches of Zoology there were forerunners 

 of the chief discoverers, but the French naturalist Cuvier, 

 mentioned above, was the first zoologist to undertake to compare 

 the structures of all the groups of animals on a wide scale. His 

 work strongly influenced his successors, particularly in France. 

 He was thus the real founder of comparative anatomy. It was 

 on the basis of these studies in anatomy that he made his con- 

 tribution to the classification of animals. Some of those who 

 continued the work of Cuvier were, Milne-Edwards (1800-1885) 



