36 STELLA BURNHAM VINCENT 



Although we were satisfied that these were not exceptional 

 animals we now cut the vibrissae of three blind animals which 

 had been used on a problem box previously. They were of the 

 same age and sex and came originally from the same group. 

 They had the advantage of previous training although of a 

 different kind and had also played on the maze all the time 

 that they were learning the other problem: that is they were 

 put on the maze to play and taken from it one by one over to 

 the problem box. They played here daily from Aug. 25, to 

 Oct. 9, forty-six days, from an hour to an hour and a half a 

 day. The maze was turned 90 degrees at the time but they were 

 always put on at D which was the point nearest to their cage 

 and made their way from here as they chose around to the food 



Error Curve ISOlrials 



/ 2 3 ^ ^ 6 



Fig. 11 — Error curve for blind rats without vibrissae — plotted for groups of 25 

 trials. 



box where enough of the odor of food remained from the preced- 

 ing experiment to attract them. From here they were taken 

 to the box upon which they were working. Thus in reality they 

 had been upon the maze as many days as the others up to this 

 point, only for far longer periods and in a perfectly free fashion. 

 When put upon the maze they always found their way imme- 

 diately around to the food box and from here ran out on the 

 maze in every direction. It might have been supposed that 

 they would have learned it from every conceivable position. 



These animals were now given fifty trials on the maze in its 

 original position and only one could run it successfully at this 

 time. This one learned to keep to the left and did so by curling 

 his toes down over the edge of the path, sometimes dragging one 

 whole foot along the edge and by keeping the pacing gait. 

 (Fig. 1 6, Plate II.) 



