A STUDY OF THE BEHAVIOR OF THE CROW 87 



If the crow merely looked into one of the compartments with- 

 out entering, the number of the compartment was recorded. 



If it, instead, entered a compartment, the number was under- 

 scored. In case the compartment entered happened to be a 

 "wrong one", the time of entrance was placed in parenthesis 

 immediately after the number of the compartment. When the 

 time exceeded a minute, the number indicating the minutes 

 was placed in a circle. For less frequent forms of behavior, 

 other provisions were found convenient, and by the use of symbols 

 and other abbreviations it was found easy to obtain a fairly 

 complete description of the subject's behavior. 



To illustrate the use of the above symbols, the following record 

 of a trial (trial 32 of number 3 on July 23), setting 1.2, is presented. 



4, 3, i_, J, l_> ®, L, o. L, 1, L, ©, (trying to get out of area), 

 L, _l, ®, J, L, J, (pkd. at hole in floor), ®, 1, o, L, 9, ©, ©, 

 ©, O, n L, 2, ®, 1, 2, 8' 13". 



In this trial, crow number 3 did not enter the wrong compartment 

 at all. The time between the fifth and the seventh minutes was 

 spent before compartment 9. 



It was decided by the experimenters that when a crow had 

 made ten correct choices in succession, its training should be 

 considered complete, or in other words, it should be said to have 

 solved the problem. 



In the case of the problem in question, crow number 3 at the 

 end of thirty-two trials had entered the right compartment 

 twelve times in succession, but in several of these trials it had 

 been aided by the experimenter, who moved the exit door slightly 

 in order to attract the attention of the bird after it had for 

 several minutes refused to enter any compartment. 



In the accompanying table 1, a summary of the trials for 

 each of the birds in problem 1 appears. At the head of the 

 several columns are the settings numbered 1 to 10, with the 

 right number in bold faced type. In the first column -at the 

 left, under each of the several settings, appears the number of 

 the trial and the series of compartments entered. Thus, for 

 example, referring to the results for crow number 3, in trial 

 number 5, which was the first trial in the regular series, the bird 

 entered compartment 8 and then compartment 9. In trial 6, 

 it immediately entered compartment 4, the right one. The 



