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manual of elementary zoology 



homologous with one another and with the hands of a man 

 and the paddles of a whale. Organs which have the same 

 function, but have arisen independently, are called analogous. 

 The wings of a bird and an insect or the legs of a rabbit and 



Suina. Ruminantia. 



Anthropoidea. 



Lemuroidea. 



MAMMALIA. 



Fig. 388. — The classification of the Mammalia arranged in the form of 

 a genealogical tree. 



a crayfish are analogous. In the same class of evidence 

 we may place the existence of vestigial organs, such as the 

 ear muscles of man, which can only be satisfactorily ex- 

 plained on the supposition that they were functional in an 

 ancestor. (3) The facts of embryology suggest evolution. 

 We have seen that different animals pass through similar 



