370 STELLA B. VINCENT 



The reasons for this have been discussed in another paper. 

 The time records are almost a direct reflection of the accuracy 

 for, although the final scores distinctly favor the olfactory and 

 black- white mazes, the advantage is but slight. The cutaneous 

 open maze is also better than the normal in all of the accuracy 

 counts, and also in final and total time. The small differences 

 in time again are probably more or less an expression of the 

 accuracy with a balance in favor of the open maze. 



In these results, then, the olfactory maze leads, the open 

 maze stands next in order while the black-white and the normal 

 mazes approach each other very closely if all of the counts are 

 considered. It will be seen that the big advantages which these 

 sensory mazes offer are found in the early trials, in the setting 

 up of the automatisms, and that the apparent total gain is due, 

 for the most part, to the gain in the early trials. The estab- 

 lished habit is practically the same no matter under what sen- 

 sory conditions it is set up. The distracting effects of some 

 of these sensory situations which affect the final scores are 

 discussed in the previous papers. 



Why some experimental workers should choose to neglect the 

 error records is still a mystery to some of us. Certainly the 

 real differences in the bits of learning given above are not shown 

 by the time records. It is more essential in the normal life of 

 a rat that it should be able to thread a beam or a cornice 

 without falling, to jump from one projection to another with- 

 out missing, to avoid being cornered and to strike its hole 

 exactly when pursued by its enemies than to run a certain 

 number of feet per second. The total distance which has been 

 a measurement warmly advocated has advantages but it does 

 not show really significant variations from the true path, although 

 there is always, we will grant, a relation between the total num- 

 ber and amount of the errors and this total distance. If a rat 

 always took the shortest way home, if it did not have its own 

 peculiar way of getting out from its hole, perhaps this measure 

 would express the facts more truly. The animal runs out into 

 the maze a little way, runs back, runs out a little farther and 

 then back, etc. This is a purely instinctive activity quite on a 

 par with those natural movements in and about a rat's hole 

 that insure it an open way home and such actions may 

 not at all signify that the path as far as traversed is not familiar. 



