224 ROBERT M. YERKES AND CHARLES A. COBURN 



by way of 3, 4 and sometimes also 6, to the middle box, number 

 5. This tendency to select, when in doubt, a box second from 

 the right end of the series may possibly be due in part to the 

 fact that the box to be chosen in setting 7 was number 2. At 

 any rate, the frequency with which the female throughout her 

 training chose box 2 first of all under setting 6 is surprisingly 

 high, whereas for the male, this frequency while rather high 

 early in the course of the training, tended to diminish and to 

 give place to the decidedly profitable tendency to choose a box 

 near the middle of the series, 6, 7 and 5 frequently being entered. 

 Similarly, w T e might, if space permitted, analyse in detail the 

 results for the other settings. We have chosen to use our space 

 in this report for the presentation of data in tabular form rather 

 than for their description, because we are convinced that the 

 facts are more important than early attempts at interpretation. 



SUMMARY 



1. The pig has proved itself an ideal subject for studies in 

 adaptive behavior. 



2. The new multiple choice method, by means of which 

 standardized problems ranging in difficultness from the very 

 easy to the very difficult may be presented to widely differing 

 types of organism, has in our opinion fully justified our expec- 

 tations, for it has proved admirably suited to the discovery and 

 analysis of increasingly complex types of behavior. 



3. For the purpose of discovering the extent to which idea- 

 tional and closely allied types of behavior exist in the pig, four 

 problems were presented. They may be defined simply in terms 

 of the constant relation of the right mechanism, as (1) the first 

 at the right end of the series; (2) the second from the left end 

 of the series; (3) alternately, the first at the left and the first 

 at the right; (4) the middle member of the series. 



The purpose of the experiments was to discover the pig's 

 reactive tendencies and especially its degree of ability to disso- 

 ciate the essential and constant relation of the right mechanism 

 from its accidental and variable accompaniments. 



4. The two subjects solved perfectly the first problem with 

 less than fifty experiences. The indications are that visual and 

 kinaesthetic guidance sufficed. 



The second problem was solved more slowly, partly because 

 the influence of the earlier training had to be overcome, but 



