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CLASSIFICATION 



THE first great biological division is into kingdoms, namely, 

 the animal kingdom and the vegetable kingdom. Then by 

 classification the vast number of existing animals and plants are 

 grouped so as to give each individual a definite place. By this 

 system a beautiful order is established, which enables the student 

 to find any particular animal or plant he may wish to study, and 

 also to know its general characteristics from the name of the 

 group to which it belongs. 



In broad generalization, objects of wide dissimilarity are rec- 

 ognized as belonging to the same kingdom, as do trees and 

 grasses, or as do birds and fishes. Certain trees or grasses and 

 certain birds or fishes have such points of resemblance that they 

 plainly show that they belong to subdivisions. The most untu- 

 tored people recognize these distinctions, but the naturalist goes 

 further and finds points of distinction which the casual observer 

 overlooks. 



The animal kingdom has a varying number of divisions, called 

 branches, subkingdoms, or phyla. Some late authors have admitted 

 twelve divisions, and have given them the name phyla. Each 

 phylum is composed of a group of animals with a plan of struc- 

 ture which is common to themselves, but differs from that of the 

 animals of all other phyla. 



The higher animals begin with the twelfth phylum, namely, 

 the Chordata, or vertebrates. These animals have a spinal 

 column, or series of vertebrae, while the lower animals, or inver- 

 tebrates are without a spinal column, and depend for stability 



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