HISTORY OF ZOOLOGY. 



Methods of Zoological Study. In the history of 

 Zoology we can distinguish two great currents, which have 

 come in contact or united in a few men, but which on the 

 whole have developed independently, nay, more often in 

 pronounced opposition to each other; these are on the one 

 side the systematic, on the other the morphologico-phy- 

 siological mode of studying animals. In this brief his- 

 torical summary they will be kept distinct from one an- 

 other, although in the commencement of zoological inves- 

 tigation there was no opposition between the two points 

 of view, and even later this has in many instances dis- 

 appeared. 



Aristotle, the great Greek philosopher, has been dis- 

 tinguished by the title of " Father of Natural His- 

 tory," which means that his predecessors' fragmentary 

 knowledge of Zoology could not be compared with the 

 well-arranged order in which Aristotle had brought to- 

 gether his own and the previously existing knowledge of 

 the nature of animals. In Aristotle favorable external 

 conditions were united with more favorable mental ability. 

 Equipped with the literary aid of an extensive library, and 

 the pecuniary means then more than now indispensable 

 for natural-history investigation, he pursued the inductive 

 method, the only one which is capable of furnishing secure 

 foundations in the realm of natural science. It is a matter 

 for great regret that there have been preserved only parts 

 of his three most important zoological works, " Historia 

 animalium," " De partibus," and " De generatione," 

 works in which Zoology is founded as a universal science, 

 since Anatomy and Embryology, Physiology and System- 



7 



