Part 3 

 ANIMAL BIOLOGY 



Chapter 17 



SURVEY OF THE ANIMAL KINGDOM 



A detailed study of the entire animal kingdom cannot be made be- 

 cause there are over 800^000 species (different kinds) which are more 

 or less well known. Only a few species which are representative of the 

 various subdivisions of the animal kingdom will be considered. 



In order to study representative species of the animal kingdom scien- 

 tifically, a system of classification must be used whereby all investigators 

 in all parts of the world may study the same species of animal and call 

 them by the same scientific name. Without scientific names and classifi- 

 cation, students in various parts of the country may apply dozens of 

 entirely different names to the same animal. For instance, such names 

 as night crawlers, fishworms, or groundworms might be applied in dif- 

 ferent localities to the same earthworm, which, by biologists the world 

 over, is known by its scientific name of Lumhricus terrestris. On the 

 other hand, if the term night crawler were applied in various communities 

 to any animal which crawled at night, there would be great confusion 

 and many entirely different animals would have the same common name. 



Greek and Latin are used in classification and scientific names be- 

 cause they are universally understood and because they are not suscep- 

 tible to changes in each local community. Because of their standardiza- 

 tion throughout the world, they are extremely desirable for scientific 

 purposes. 



Complete scientific descriptions and classifications of animals also 

 make it possible to identify accurately unknown animal species no matter 

 when or where found. Without scientific terms and classifications, each 

 investigator would have to make his own classification and follow his in- 

 dividual ideas of naming. If this procedure were universally followed, an 



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