INTRODUCTION 

 CHAPTER 1. 



The average course in general Zoology uses marine animals for many of 

 its type forms, so that the student gets the impression that only at the sea' 

 shore can one study animal life in any abundance. As a matter of fact, the 

 land and fresh-water animals include members of all the major groups or 

 phyla of animals except the Brachiopods, Ctenophores and Echinoderms, which 

 are exclusively marine. Brachiopods and Echinoderms are abundant in the 

 limestone regions of our country as fossil remains, indicating that these areas 

 were formerly ocean floors. Since the majority of our population lives away 

 from the coast most of the time, some knowledge of and interest in inland 

 animals seem highly desirable. 



From ancient times man has been interested in naming animals. Aristotle, 

 who lived about 350 B. C, appears to have known about five hundred animals 

 by name. Linnaeus, who started our present system of nomenclature and 

 who, living from 1707 to 1778, had the advantage of receiving many speci' 

 mens from America, recorded the names of over five thousand. Today we 

 recognize several hundred thousand species of animals, and more are continually 

 being named. 



Various systems of nomenclature have been proposed at different times, 

 but a modification of that proposed by Linnaeus, being most flexible and 

 adaptable to our modern ideas of the relationship of all living things, has been 

 universally adopted. We now divide the animals into large groups called 

 Phyla. Each Phylum is, in turn, divided into Classes, each Class into Orders, 

 each Order into Families, each Family into Genera, and each Genus into 

 Species. Linnaeus' great inspiration was to use the Latinized name of genus 

 and species as the general scientific name of each animal, thus enabling the 

 scientist to learn one name instead of a different common name in each 

 language for each animal. So now to American, Russian and Japanese alike 

 the name of man is Homo sap:ens, the dog Cams famiharis, and so on. Thi.= 

 scientific name was intended to be a description in itself, the name of the 

 genus being a noun and the name of the soecies usually an adjective. 



The student of Taxonomy or Classification is at first likely to be puzzled 

 by the lack of agreement among different writers as to the major groupings. 

 The early scheme of classification was merely to establish a convenient catalogue 

 for ready reference. The modern idea is that the system of classification 

 should also express the degrees of relationship existing between the various 

 animals. Scientists, like laymen, often disagree as to the interpretation of 

 evidence and therefore do not wholly agree on taxonomic groupings. 



