ACKNOWLEDGMENTS 



It is a pleasure to acknowledge my deep obligation to Prof. 

 Harvey A. Can* both for setting the problem and for the careful 

 supervision and criticism of the work here presented. To Prof. 

 James R. Angell also I owe much. Not only has he subjected 

 the monograph to a searching analysis; but, through that im- 

 palpable something called "laboratory atmosphere," he has 

 influenced the tone of the interpretations. Prof. John B. Watson 

 of Johns Hopkins University has read a first draft of the theo- 

 retical section of this paper. I wish to add a word of thanks 

 to Mr. W. R. Hough and Dr. H. B. Reed for the guidance given 

 me by the data which they had accumulated in an early study 

 of the present problem. Further notice of their work is given 

 below. Mr. De Vry, director of the Zoological Garden in Lincoln 

 Park, Chicago, and Dr. Homaday, director of the New York 

 Zoological Garden, have both given me information concerning 

 the habits of raccoons. 



