30 JOSEPH PETERSON 



circumstance of the maze enviromnent.'^ This seems to iriiply 

 that the effect of one stimulus holds over into and conditions 

 effects of later stimuli. 



■ The third point to note in our results is that when any given 

 cul de sac is shortened it is eliminated more readily than when 

 left at full length. That is to say, other things equal, and 

 within certain limits, a long cnl de sac is eliminated less readily 

 than a short one. This statement is amply borne out in our 

 data both from the A- and the B-mazes. The general results 

 of all our experiments are shown roughly in the accompanying 

 diagram, figure VI, representing the total number of entrances 

 to each of the blind alleys in the various mazes. The heavy 

 black columns and the double lines represent the totals for 

 the full length and the shortened blind alleys, respectively, in 

 the B-mazes; the single continuous and the broken lines stand 

 for the corresponding totals for the A-maze blind alleys. In 

 the B-mazes the total entrances to the full length ctd de sacs 

 is 1311, while the total number of entrances to the same ctd 

 dc sacs when shortened, by an equal number of animals under 

 the same conditions, is 929, a decrease of 29%. This decrease 

 would doubtless be considerably greater but for the fact that 

 confusions by the long blind alleys resulted in random behavior 

 which increased the totals for the shortened cul de sacs. For 

 instance, table I shows that more entrances were made into 2 

 short than into 2 full length. This was very clearly due to 

 the fact that as long as the habit to avoid 1 was incomplete 

 the animals in the confusion also entered 2. It will be recalled 

 that in the A-mazes the cid de sacs were all full length in the 

 one and all shortened to about half their length in the other case. 

 Here we do not have the confusion noted in the B-mazes. The 

 shortened blind alleys were entered 47% fewer times than those 

 of full length. This bears out the conclusions drawn from the 

 B-mazes. 



The effect of shortening the ciil de sacs was most noticeable 

 in the case of 1 in the B-mazes, which was by all means the most 

 difficult to eliminate. Being the first to encounter, it was 



'^ On this point our results agree with some aspects of those by Peckstein, L. A. 

 Whole vs. Part Methods in Motor Learning: a comparative Study. Psych. Man., 

 Ser. No. 99, 1917. " Each aspect of the course is no doubt associated with and 

 located in reference to all the details of the course and to the entire objective en- 

 vironment as well." P. 30. 



