MENTAL LIFE OF MONKEYS AND APES 



15 



A 



w 



W' 



Figure 17. — Ground plan of multiple-choice apparatus in experiment room A. 



1 

 Scale — 

 60 



A, record stand; C, bench for observer; B, step as approach to C; D, alleyway 

 leadmg to E, response-compartment; F, one of the nine (1-9) similar multiple- 

 choice boxes; G, H, alleyways leading from boxes to starting point at D; L alley- 

 way used by experimenter as approach to rear of apparatus; W, W, windows; 

 P, alleyway; Z, large cage; 16, entrance to room A; 17, entrance to apparatus and 

 thence via 10 to cages; 18, entrance to alleywav I; 11, 15, entrances to D; 12, en- 

 trance to E; 13, entrance door of box 5; 14, exit door of box 5; o, cover for food 

 receptacle. 



