HABIT FORMATION IN THE ALBINO RAT 23 



ratio to each other. The exceptions occur when the time record 

 is increased on account of failures (each of which means a count 

 of 900 seconds) in the first part of the learning process. In a 

 trial which has one or more failures as a component part, the 

 distance run is never proportional to the time spent, since if 

 the rat does not refuse to run altogether after several vain 

 efforts to reach the center, it will make frequent halts at the 

 radial stops and at the entrance to the maze. It appears that 

 we have here additional evidence for considering the distance 

 as a more accurate measure of the learning process than the time. 

 According to the averages which appear below, the females 

 of this group are superior to the males in number of trials re- 

 quired to learn, and in final efficiency (absolute time), but 

 inferior in total time consumed, total distance covered, and 

 speed attained throughout the learning process, so that on the 

 whole, the males may be considered as slightly superior to the 



females. 



Time 



Trials Absolute Total Distance Speed 



Males 32 5.7 sec. 213 min. 277.1 m. 21.6 cm. per sec. 



Females.. 29 5.6 " 232 " 267.8 19.2 " " " 



SIXTY-FIVE DAY RATS 24 



These rats began the problem when sixty-five days old, and 

 were fed in the maze for one week before actual experimentation 



24 A group of twenty-seven thirty-five day rats was used early in the experi- 

 ment, but the results obtained from their records were so at variance with those 

 for other groups that it was felt there must have been some error in the experi- 

 mental work. Accordingly a control group consisting of thirteen rats was trained 

 near the close of the experiment, with no better results so far as consistency with 

 the main body of averages of the other groups was concerned, but with exactly 

 opposite results from those of the first thirty-five day group. Therefore neither 

 set of figures is given in the body of this paper, since still further work is neces- 

 sary at that age before any statements can be made regarding it. The averages 

 obtained for the two groups are given below: 



Time 



Trials Absolute Total Distance 



First group 63 6.7 sec. 564 min. 552.2 m. 



Control group...... 22 7.3 160 156.7 " 



