PREFACE 



The course for which this book of laboratory directions was prepared 

 is a recognition of the growth which the science of Zoology has made 

 in the past several decades. No longer a purely morphological subject, 

 zoology is not in the opinion of the authors properly treated in a purely 

 morphological course. Good teachers have long recognized that dis- 

 section and classification alone would not make a zoologist, and have 

 striven in lectures and recitations to provide the larger outlook which the 

 science has come to possess. But this recognition seems hardly adequate. 

 If in the lectures and recitations due attention is paid to the type dis- 

 sections in the laboratory, morphology can scarcely avoid receiving an 

 emphasis it does not deserve. If to avoid this over-emphasis the recita- 

 tions and lectures are devoted exclusively to evolution, distribution, 

 ecology, genetics, etc., the laboratory exercises and recitations must seem 

 unrelated to one another. Recitations and laboratory work thus become 

 two courses which the student pursues simultaneously. 



The only solution has appeared to be to make the laboratory work 

 itself bear on the large questions of biology. The laboratory work may 

 thus have a balance of its own, it does not need to be averaged with the 

 recitations. This book contains directions .for first-hand exercises which 

 we believe have the emphasis properly placed. Morphology still receives 

 more attention than any other division of the subject, but it is nearly 

 everywhere directed to some end which is not merely structure. 



The large number of inquiries received concerning this course, indi- 

 cating a widespread belief that some plan of this kind is preferable to 

 the usual type course, have led us to make the book available for use in 

 other institutions. Many details of the course may well be altered. One 

 form will often illustrate a point as well as another form. In a number of 

 instances alternative tasks are provided ; others will occur to the experi- 

 enced teacher. 



In the preparation of the laboratory directions every member of the 

 Zoology Department of the University of Michigan has had a share, 

 either in original organization or subsequent revision. Besides those 

 mentioned on the title page as authors, special mention is due to Pro- 

 fessors Jacob Reighard, E. C. Case, R. W. Hegner, and Paul S. Welch, 

 and Mr. George E. Johnson. 



A. FRANKLIN SHULL. 



August, 1919. 



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