vi PREFACE 



From time to time directions for the preparation of draw- 

 ings are inserted. It is the writer's hope that these draw- 

 ings will be used by the student as a means to the correla- 

 tion of the anatomical details he has verified, rather than 

 by the instructor as a method of judging the proficiency of 

 the student. Frequent oral quizzes and demonstrations 

 help make the laboratory a dissecting-room, instead of a 

 drafting-room, as is too often the case. 



Following the account of the anatomy of the adult frog, 

 there will be found sections on the histology and embry- 

 ology of this form. It is hoped that these will be useful 

 in those laboratories where the frog plays the central role 

 in the beginning course. 



The terminology employed has been carefully compared 

 with that of Holmes, which is followed as a general rule. 



In conclusion, the writer wishes to express his apprecia- 

 tion of the kindness of his colleague, Dr. A. R. Cahn, in 

 reading the manuscript and making many helpful sug- 

 gestions. 



Waldo Shumway. 

 Urbana, III. 



April, 1928. 



