50 
CURT P. RICHTER 
The results obtained from this experi¬ 
ment (see figure 23) showed: (1) In this 
situation where the animals had free 
access to food all the time the periods 
of activity and inactivity come and go 
with the same regularity as before only 
at a slower rate from six to ten per 
twenty-four hours. (2) The animals 
enter the food box at least once during 
each activity period, occasionally twice. 
(3) The time spent in the food box 
compared with the length of the entire 
period is very short. (4) The entrance 
into the food box does not take place at 
the beginning of the activity period but 
usually toward the end. Only in a few 
cases did any of the animals enter the 
food box at the beginning of a period. 
No instance of an entrance between 
periods was recorded. (5) The amount 
of activity increases progressively from 
the beginning of each period to the point 
when the animal enters the food box. 
(6) There is always some activity after 
the animal returns from the food box. 
This activity consists chiefly in all kinds 
of cleansing manoeuvers very much like 
those of an ordinary house cat. (7) The 
activity which precedes the entrance into 
the food box is diffuse and undirected. 
It consists usually of such movements as 
jumping, climbing, playing with paper, 
sniffing and gnawing at the sides of the 
cage, etc. The element of search for 
food plays no role in this activity. The 
animals are so thoroughly adjusted to 
every part of the cage that the necessity 
of search drops out entirely. 
