ZOOLOGY 



INTRODUCTION 



Zoology, the branch of Natural History which deals with 

 animals, is one of the two subdivisions of the great science Biology, 

 which takes cognisance of all organisms, or things having life, as 

 distinguished from such lifeless natural objects as rocks and 

 minerals. The second of the two subdivisions of Biology is 

 Botany, which deals with plants. 



The subject-matter of Zoology, then, is furnished by the animals 

 which inhabit the land-surface, the air, and the salt and fresh 

 waters of the globe : the aim of the science is to find out all that 

 can be known of these animals, their structure, their habits, their 

 mutual relationships, their origin. 



The first step in the study of Zoology is the recognition of the 

 obvious fact that the innumerable individual animals known to 

 us may be grouped into what are called species, the members of 

 which resemble one another so closely that to know one is to know 

 all. The following example may serve to give the reader a fairly 

 accurate notion of what Zoologists understand by species, and of 

 the method of naming species which has been in use since the time 

 of the great Swedish naturalist Linnaeus. 



The Domestic Cat, the European Wild Cat, the Ocelot, the Leopard, 

 the Tiger, and the Lion are animals which agree with one another in 

 the general features of their organisation in the number and form 

 of their bones and teeth, in the possession of retractile claws, and 

 in the position and characters of their internal organs. No one 

 can fail to see that these animals, in spite of differences of size, 

 colour, markings, &c., are all, in the broad sense of the word, 

 " Cats." This is expressed in the language of systematic Zoology 

 by saying that they are so many species of a single genus. 



According to the system of binomial nomenclature introduced^by 

 Linnaeus, each kind of animal receives two names one the generic 

 VOL. I B 



