10 JOSEPH PETERSON 



3:40, and 8:30-8:40,— total runs, twenty-four for each rat. All 

 records were left incomplete, but all rats were equally practiced 

 to the point of discontinuance. All animals were eager and 

 active. 



Maze IIB 



Nil Group 8 females (15, 17, 19. 20, 21, 22, 23, 24). 



Rat 20 was blind in left eye. Distribution of practices pre- 

 cisely same as for Group Mii, in Maze IB, same days. 



R/ Group 4 males (1, 5, 7, 8) trained in lA. 



Distributions of practice same as for St, Maze IB, same days, 

 Practice periods, Aug. 29th and 30th: 9:25-9:35, 9:55-10:10. 

 3:15-3:30, 3:40-3:55, and 8:45-9. All records left incomplete; 

 rats eager and active. 



Maze IA 



Ru Group 4 males (1, 5, 7, 8). 



Practice distributions same as for M», Maze IB. 



N/i Group 4 females (15, 20, 21, 22), trained on Maze IIB. 



Three runs daily for each rat until habit was completed, eight 

 runs of ten correct. 



M/i Group 3 females (9, 13, 14). trained on Maze IB. 



By intensive method : the three animals were given three runs 

 each, alternating with short periods of rest, during the forenoon 

 of Aug. 28th. Rat 14 completed habit in twenty-eight runs, 

 or trials: rat 9, in twenty-four runs; rat 13, in forty-one runs, 

 eleven of which were made early the morning of the following 

 day. All rats were eager and active, except 13 on the last run 

 of first day, when it took sixteen seconds following two runs of 

 two seconds each. 



Maze IIA 



Su Group 4 males (4, 6, 3, 2). 



Practice distributions same as for the Ru Group in Maze IA. 



N/o Group 4 females (17, 19, 23, 24), trained on Maze IIB. 



Practice distributions same as for N/i in Maze IA. 



M/i Group 3 females (11, 16, 18), trained on Maze IB. 



Practice distributions same as for M/i, and alternating after 

 each three trials with them. Each rat completed the habit, 

 getting eight out of ten runs correct, in a total of twelve runs. 

 All were very active and eager throughout. 



This schedule is given as actually carried out, not exactly 

 as originally planned. It will be noted that the programs for 

 the two B-mazes are precisely alike, and that the same is true 

 of the A-mazes. This affords means of control of a number 

 of factors which otherwise might favor one or the other of the 

 control groups. Temperature conditions changed considerably; 

 it was also necessary to modify occasionally, to suit the time 

 at the disposal of the experimenter, the number of runs per 

 day by each animal. At the early stages of the learning there 

 was not enough time to give each animal more than two runs 



