TRIAL AND ERROR REACTIONS IN MAMMALS 



45 



clawed it for several minutes, then turned away from this door 

 and wandered about the apparatus ; one effort to open an exit 

 door was recorded. Then he returned to Door 4 and again 

 spent some time in alternately clawing and barking at it; when 

 he left the door a second time a second effort was recorded. He 

 returned to it, tried it and left it a third and a fourth time before 

 attacking another door, hence his first four separate activities, 

 all of which were definitely directed against the same unyield- 

 ing door, were recorded as four separate efforts to open exit doors. 

 With the above in mind the reader will be able to obtain a 

 general orientation concerning the value of the situations for 

 each of the various subjects. 



TABLE 1 



Subject. Age. 



Man 1 34 years 



Boy 7 15 years 



Boy 6F1 13 years 



Boy 5F1 12 years 



Boy 4F1 10 years 



Boy 3 10 years 



Girl 1 10 years 



Boy 2F1 8 years 



Boy 1 26 months 



Man A 45 years 



Boy A 11 years 



Monkey 6 15 years 



Monkey 4 1-5 years 



Monkey 3 5 years 



Monkey 2 15 years 



Monkey 1 1-5 years 



Dog 1 3 years 



Dog 2 1 year 



Dog 4F2 . 116 days 



Dog 6F2 109 days 



Dog 3F1 102 days 



Dog 8F1 : 95 days 



Dog 5F2 88 days 



Dog 7F1 81 days 



Dog 10F2 74 days 



Dog 9F1 67 days 



Dog llFl 60 days 



Dog 12F1 53 days 



Dog 14F1 46 days 



Dog 13F2 43 days 



Dog 16F2 43 days 



Dog 18F1 36 days 



Cat 1 1 year . . 



Cat 2 1 year 



Cat 3 1 year 



Cat 7 70 days 



Cat 5 56 days 



Horse 1 8 years 



No. of efforts 



to open exit 



doors. 



200 

 193 

 201 

 216 

 194 

 211 

 183 

 216 

 315 

 217 

 237 

 275 

 291 

 278 

 272 

 278 

 324 

 302 

 346 

 329 

 284 

 378 

 304 

 357 

 427 

 389 

 358 

 307 

 413 

 314 

 376 

 438 

 358 

 378 

 320 

 406 

 368 

 461 



