146 STELLA B. VINCENT 



animal yet the time average is 13.5 minutes. The record for 

 the second trial is practically the same. Almost the same average 

 number of errors, 4.1, was made by the normal animals in the 

 fifth trial in an astonishingly shorter time. For the first trip 

 without error these rats had an average time of 160 sec. The 

 time record for fifteen rats in the normal maze for the first perfect 

 trip is less than one-fifth of this — 30 sec. In final speed, however, 

 these animals excel. This maze has an average record of .28 

 min. for the last five trials as against .31 min. for the normal 

 maze. This is a difference of nearly two seconds — an appreciable 

 difference when one remembers that the maze can be run in 

 ten seconds. 



The time curve (Fig. 1) is very unlike the usual time curve. 

 Compare it with Fig. 3. It is not the beginning height which is 

 remarkable but the persistence with which it maintains this 

 level — the slow rate of elimination of the surplus time. Forty- 

 seven per cent of the surplus time was eliminated in the normal 

 maze in the second trial, in the olfactory maze only 2.5% was 

 eliminated at this time; 80% was eliminated in the first four 

 trials in the normal maze, but it took the rats in the olfactory 

 maze nine trials to reach this point. By the tenth trial the 

 animals in the normal maze had only 2% surplus time left to 

 eliminate, but the rats in the olfactory maze did not fall per- 

 manently below this 2% point until the twenty-fifth run. 



It must be clearly evident that this olfactory trail was affecting 

 the learning process but before any definite conclusions were 

 drawn it was necessary to put the trail in the cut de sacs, instead 

 of the true path and to see what would happen then. 



EXPERIMENT II. TRAIL IN CUL DE SACS 

 1. Behavior 



This experiment was conducted exactly like Experiment 1, 

 with animals of the same age, etc. The only difference was in 

 the trail which was laid from the entrance of each cut de sac to 

 its extreme end. There was a noticeable difference in the numer- 

 ical results as well as in the behavior under these conditions. 



The animals in this maze also made fewer errors from the 

 beginning than the animals in the normal maze and the speed 

 was greater also. When put in the maze the rat ran, as in the 

 usual maze, headlong down the runways. Soon he blundered 



