The Mental Life of Monkeys and Apes:
A Study of Ideational Behavior


ROBERT M. YERKES
Harvard University




BEHAVIOR MONOGRAPHS
Volume 3, Number 1, 1916
Serial Number 12
Edited by JOHN B. WATSON
The Johns Hopkins University


WITH SIX PLATES AND FIVE TEXT FIGURES






CONTENTS

I. Interests, opportunity and materials

II. Observational problems and methods