CANADA PORCUPINE 65 



alleys eA'en to the end and returned directly he was charged 

 up with one error. If he ran back and forth while inside, each 

 false turn was counted an error of equal value as was also his 

 failure to take the proper course on coming out. To turn back 

 when on the right route provided he made any progress was 

 scored an en^or — mere turning around not being so considered. 

 Entrance into x was called an error if he returned and took the 

 short course but not if he eventually took the long course. 

 Entrance at 4 was considered an error as he could never make 

 progress if he formed the habit of taking that path. The experi- 

 menter found it most convenient to take a position in the center 

 while making records. This seemed most advisable as it took 

 away the strong counter stimulus of the animal trying to get 

 to the experimenter for food if he were in sight in another direc- 

 tion. In addition, it gave the normal stimulus that where the 

 experimenter was there was the food, and thus kept the animal 

 at work. On the other hand, the maze was so constructed that 

 a strong stimulus in the direction of the center tends to cause 

 the animal to enter each of the cul-de-sacs, unless it should be 

 5. The correct route leads away from the center at the parting 

 of the ways in other cases. Thus it would seem, that the pres- 

 ence of the experimenter in the center, increasing the stimulus 

 many fold it may be, would interfere with the progress of the 

 animal rather than assist him in finding the way. 



The results obtained with No. 6 lend themselves very well to 

 a somewhat detailed study. This porcupine had just finished the 

 form tests and was thus completely tame though he had the 

 following tendency less strongly than some of the other animals 

 included in this study. He had always to be coaxed out of the 

 den for experimentation. When he was once out, however, he 

 worked steadily to the close of each series of experiments. 



The maze was located in the basement of the barn in a room 

 with a floor of earth. The room was well lighted by two large 

 windows on the side opposite the entrance of the maze. The 

 living room of the animal was in the direction marked p on the 

 chart at a distance of 12 feet from the nearest edge of the maze. 



Experiments were performed dail}^ for one week as follows: 

 First day, i; second day, 2; third day, 5; fourth day, 12; 

 fifth day, 12 ; sixth day, 16. Details in time and errors for this 

 series of experiments are presented in table XIII. 



