23 



in the working time, and henoe the feeding time caused no notice- 

 able change in the behavior of the rata, marked disturbance re- 

 sulted from a delay of four or five hours. 



In general, the behavior of individuals of each group on 

 first entering the maze was the same. The rats showed great 

 hesitancy in leaving the starting box^ returned to it frequently 

 after finally entering the maze proper, and endeavored to push 

 up the sliding door; they were also to leave a familiar alley 

 for one unexplored, became excited when a stop was encountered, 

 trying repeatedly to push it aside or to gnaw through the 

 mesh top, and made frequent efforts to escape from the maze. 

 Departure from this type of behavior was noticed among the very 

 old rats aad the very young ones. Many of the former evidenced 

 no excitement whatever, often slee^-ing for several minutes 

 between periods of activity, while the latter were far more ac- 

 tive than the rats of any other group, and showed no hesitancy 

 in entering unfamiliar portions of the maze. 



The time usually decreased very rapidly, the distance less 

 so, during the first three or four trials. For example, on its 

 first trial, rat 34 of the 300 day group required eleven minutes 

 and forty seconds to reach the food and the distance covered was 

 forty -nine and six-tenths meters. On its second trial, seven 

 minutes six seconds were required, and the distance run vias thirty 

 and nine-tenths meters; at the fourth trial success was attained 

 after 1 minute nineteen seconds; the pathway traversed measuring 

 ten and two-tenths meters, while for the sixth trial the time 

 record was only forty-nine seconds, the distance eight and six- 

 tenths meters. By the tenth or fifteenth trial the decrease in 



