PREFACE 



While there are a few so-called "economic zoologies" on the market, 

 there is none known to the author that makes the economic aspect of the 

 subject the main, point of attack, with morphology, habits, etc., 

 secondary. Hence this volume which is based upon a brief course 

 in economic zoology given by the author for several years in West 

 Virginia University. 



The book may be used in several ways. As followed by the author, 

 the course may be given as a separate one to students who have already 

 had the regular elementary course in general zoology. In this case 

 the students will be familiar with the classification, structure and habits 

 of most of the type forms discussed, but, if desired, additional labo- 

 ratory work maybe arranged for the study of certain parasitic and other 

 economically important forms not generally considered in a general 

 laboratory course. Or, the text might be used in a beginning course 

 in zoology by some amplification of the morphologic and other aspects 

 and considerable increase in laboratory work. Again, it could well 

 be used as supplementary reading with, say, one hour credit per 

 semester for the year, in connection with the regular elementary course 

 in general zoology. 



It is thought that, used in one or other of these ways or in some still 

 different way, it should be especially useful to students in agriculture, 

 who want a "practical" course. 



Various sources of information have been drawn upon, and 

 recognized authorities in each subject consulted so far as possible. The 

 publications of the Government, especially those of the Department 

 of Agriculture, have been freely used and quoted. 



The figures have been borrowed largely, either from technical or 

 from more popular works, whichever gave the best ideas of the animals 

 portrayed; the source is indicated in every case. 



The brief bibliography at the end of the book is merely to aid the 

 student, who may have become especially interested in some animal 

 or group, to get more detailed information. 



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