WITH SIX PLATES AND FIVE TEXT FIGURES
I. Interests, opportunity and materials
II. Observational problems and methods
III. Results of multiple-choice experiments:
1. Skirrl, Pithecus irus 2. Sobke, Pithecus rhesus 3. Julius, Pongo
pygmaeus
IV. Results of supplementary tests of ideational behavior:
1. Julius, Pongo pygmaeus:
Box stacking
experiment
Box and pole experiment
Draw-in
experiment
Lock and key test
2. Skirrl, Pithecus
irus:
Box stacking experiment
Box and pole
experiment
Draw-in experiment
Hammer and nail
test
Other activities
3. Sobke, Pithecus
rhesus:
Box stacking experiment
Draw-in
experiment
Box and pole experiment
Other activities
V. Miscellaneous observations:
1. Right- and left-handedness
2. Instinct and
emotion:
Maternal instinct
Fear
Sympathy
VI. Historical and critical discussion of ideational behavior
in
monkeys and apes:
1. Evidences of ideation in monkeys
2. Evidences of ideation