PREFACE TO THE SECOND EDITION 



This new edition of the "Laboratory Directions in General Zoology" 

 has been revised to conform to the second, revised edition of the "Text- 

 book in General Zoology" by Curtis and Guthrie. No extensive 

 alteration of directions that have been used for so many years has 

 seemed desirable, although changes in sequence and procedure have 

 been introduced where our experience has shown them to be effective. 

 The course in General Zoology at the University of Missouri now con- 

 sists of three one-hour lecture periods and two two-hour laboratory 

 periods for one semester. The omission of certain exercises and the 

 substitution of demonstration of dissections by students, or frequent 

 laboratory quizzes, for the more time-consuming required drawings for 

 some exercises have made it possible to study the same amount of 

 material as before. However, the requirement of a drawing record 

 remains in most of the exercises, to be utilized or not as the instructor 

 desires. 



Since the appearance of the First Edition many users of the Direc- 

 tions in our own laboratory, as well as in other institutions, have made 

 suggestions which are gratefully acknowledged. We are particularly 

 indebted to our colleagues. Dr. Rudolph Bennitt, Dr. Katharine R. 

 Jeffers, Mr. John A. Cameron, and Mr. C. Kenneth Collings, for sug- 

 gestions with reference to the preparation of this edition. Such illustra- 

 tions as are new have been drawn by Miss Coral Fleenor, biological 

 artist of the University of Missouri. 



University of Missouri 



Columbia, Missouri 



May 30, 1933 



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