54 ECONOMIC ZOOLOGY AND ENTOMOLOGY 



Because as there is but one animal genus named Canis and 

 that is a member of the family Canidas, which in turn is a 

 member of the order Carnivora, which is a member of the 

 class Mammalia, which, finally, belongs to the great branch 

 Chordata, we have indicated all the superior groups by naming 

 the generic one only, and have pointed out what particular 

 species of that genus we are referring to, when we simply 

 say or write Canis familiar is. 



There are many rules of custom which zoologists try to 

 follow in deciding on names for new kinds and groups of ani- 

 mals, but they are too many and too technical to discuss here. 

 However it is worth while to point out that while the scientific 

 name of an animal may be more or less descriptive by the 

 meaning of its genus and species words, it is not necessarily 

 so. Canis familiaris is, translated, the common dog; Canis 

 latrans, the barking dog; and Caws occidentalis the western dog, 

 which are all therefore names of descriptive nature. But 

 there might be a wolf named Canis smithi, which would not 

 describe it at all. The name however would be a perfectly 

 proper scientific name. There are indeed hundreds of scien- 

 tific names which have no or almost no descriptive significance 

 at all; and some that are even wrongly descriptive. For ex- 

 ample a Russian naturalist might find in the wilds of Siberia 

 a new kind of wolf, larger than any other kind known. He 

 might name it therefore, descriptively, Canis maximus, the 

 largest wolf. In the next year an American naturalist might 

 find a still larger species in the heart of Alaska. But the name 

 Canis maximus would always be used for the smaller Siber- 

 ian wolf, because the scientific name is primarily a symbol, 

 an arbitrary name, and not a description. And also the ad- 

 vantage of having the first name Applied to a species retained 

 for all time is very great. The stability of the system and its 

 convenience depend largely on the custom of not changing the 

 names unless absolutely necessary because of some original 

 mistake in assigning the species to a wrong genus, or the 

 necessity of dividing too bulky genera into smaller ones. 



Branches and Classes of Animals. The following table gives 

 the names and arrangement of all the branches and classes of 



