8 INTRODUCTION 



such definitions imply, it would be unfortunate if too much defin- 

 ing should give the impression that Zoology consists of many, 

 isolated fields of knowledge. An understanding of the table 

 corrects such an impression. Anatomy, Embryology, Physiology, 

 and the other sciences are merely different angles from which the 

 study of animal life may be approached. Reflection will show 

 that each overlaps others and that none is isolated by the nature 

 of its subject matter. The problems and sciences defined in the 

 foregoing paragraphs and illustrated by the tabulation will all be 

 considered in the present course of study. 



Note.— Italics are used throughout the present voKime, as in Chapter 1, 

 to emphasize the names of important parts or processes. Unfortunateh', 

 the font of type used for these itahcs does not show without close inspection 

 the difference between the diphthongs (v (iv) and cc (a-). The student should, 

 therefore, bear in mind this difficult}', and when in doubt as to the spelling 

 of an italicized word containing one of these diphthongs should note the 

 spelling where the word is printed in the regular type. 



