378 Coe — A Century of Zoology in America. 



ity have in recent years successfully adopted an experi- 

 mental aspect and have made significant progress 

 thereby. Biology has now taken its place beside chem- 

 istry and physics as an experimental science. 



The latest great advance in biology has been in the field 

 of heredity. The rediscovery of the Mendelian principles 

 of heredity in 1900 brought to light the most important 

 generalization in biology in recent times. The new 

 science of genetics is essentially the experimental study 

 of heredity. 



We are at the moment in the midst of an effort to 

 establish in biology a few relatively simple laws by using 

 for the purpose the vast accumulations of observational 

 data gathered in past years, supplemented by such exper- 

 imental data as have been provided by these more recent 

 investigations. Such hypotheses as have been formu- 

 lated are for the most part only tentatively held, for their 

 validity is generally incapable of a critical test. But 

 wherever such tests have been possible, the laws of math- 

 ematics, physics and chemistry are found applicable to 

 biological phenomena. 



The number of investigators has now become so great 

 and their activities so prolific that the list and synopses 

 of the zoological publications each year cover upwards 

 of 1000 to 1500 pages in the International Catalogue of 

 Scientific Literature. 



American Leadership. — During the first half of the 

 century the progress of zoology in America remained dis- 

 tinctly behind that of Europe. At the beginning of the 

 century the science was farthest developed by the French 

 and English, although Linnaeus was a Swede and took his 

 degree in Holland. Under the influence of Von Baer and 

 his monumental treatise on embryology (Ueber Entwick- 

 lungsgeschichte der Thiere, 1828), and supported later 

 by the great physiologist, Johannes Muller, whose "Phy- 

 siologie des Menschen" (1846) forms the basis of modern 

 physiology, the German school forged rapidly ahead and 

 eventually assumed the leadership in zoology, as in sev- 

 eral other branches of science. 



In the latter half of the century the influence of the 

 German universities dominated in a large measure the 

 zoological investigations in America. The reason for 

 this is partly due to the fact that many of our young 

 zoologists, after finishing their college course, com- 



