IV 



ROLL CALL 



Preview. Earh^ contributions to classification • Binomial nomencla- 

 ture ■ Law of priority • What is a species? • A classification of plants and 

 animals • Classification of the plant kingdom • Classification of the animal 

 kingdom ■ Glossary of terms occurring in the Roll Call. 



PREVIEW 



It is hoped that this section will be freely used by the student. 

 It is not expected that the classification of plants and animals will be 

 learned by rote, but rather used for reference from time to time as 

 new forms are seen. By this means the diagnostic characteristics 

 of different phyla and classes will gradually be learned as needed, and 

 the relationship of one group to another become more apparent. 



In order to enjoy hikes or longer trips, the student should be able 

 to recognize the larger groups of the plant and animal kingdoms. 

 Fortunately there are museums, botanical gardens, and zoological 

 parks to which one may refer, all the more intelligently of course if he 

 has himself first discovered living animals and plants. 



Identifying plants and animals correctly becomes more of a plea.s- 

 ure than a task, if the principles of scientific, as well as common, 

 nomenclature are understood. Both scientific and common names 

 will be encountered. The former are written in the dead, unchanging 

 Latin language, and are of more universal usefulness, since the latter 

 are frequently misleading and confu.sing, as more than one common 

 name may be applied in different countries, or in different parts of the 

 same country, to a single plant or animal. For example, the common 

 "chain pickerel" is listed under the scientific name of Esox, indicating 

 the larger or generic group to which the fish belongs, and niger, which 

 is its specific name, but it has at least twenty-two connnon names in 

 different parts of this country. Here are a few of them: black 

 pickerel, pike, common eastern pickerel, duck-bill pickerel, green p'lkv, 

 little pickerel, and lake pickerel. The terms pike, pickerel, aii.l lake 

 pickerel are also quite commonly used in some parts of the country 

 to designate another fish, the great northern pike, Esox lucius. In 

 still other localities "pike" refers to an entirely different group, the 

 pike-perches, belonging to the genus Stizostedion. This examph^ will 



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