ZOOLOGY. 



INTRODUCTION. 



I. Subdivision of tlie Animal Kingdom. 



There are animals so like one another that they are 

 given the same name. Such animals are ranked in 

 the same species. Animals whieh dififer so much that 

 they have to be referred to different species, but which 

 notwithstanding agree in the majority of their cha- 

 racters, especially the most important ones, are placed 

 in. the same genus. Hare and rabbit, or horse and 

 donkey, are reckoned as diflferent species of the same 

 genus. Genera resembling one another are united 

 into a family ; thus, the pine marten and the beech 

 or stone marten both belong to the Marten genus 

 (Martes), while the weasel and stoat are different 

 species of the Weasel genus (Mustela) ; but these two 

 genera are so similar that they are both placed in 

 the same family, i.e. the Weasel family (MustelidEe). 

 Nearly related families together build up an order. 

 Thus, the Weasel family. Dog family, Cat family, etc., 

 collectively constitute the order of Garnivora, cha- 

 racterized, speaking generally, by the same kind of 

 teeth, claws, habits, and food. Several related orders 

 are united into a class. Thus, for example, carnivorous 

 animals (Carnivora), ruminating animals (Ruminantia), 



B 



