34^ yourtjal of Comparative Neurology and Psychology. 



3. Care of Animals. 



During the progress of the experiineiits the animals were kept 

 in the laboratory all the time. They were grouped one, two, and 

 three in small cages, the aim being to secure for each, congenial 

 cage-mates, — not an easy thing to do with the full-grown animals. 

 The cages were cared for and food was given daily by the keeper. 

 The Park Venterinarian, Dr. Blair, stopped occasionally to see that 

 the animals were in good health. ISTo other persons had access to 

 the laboratory, except the experimenter and persons whom he in- 

 vited to be present at experiments. 



The animals were then kept in a normal condition, undisturbed 

 by the crowds of visitors which thronged the Primates' House dur- 

 ing the summer. Eifort was made to eliminate fear. The experi- 

 ment cage was large and light and the animals were fed in it so 

 often that they were glad to get into it. N'o effort was made to 

 handle the monkeys with the hands in transferring them from one 

 cage to another. They were allowed to go down a runway, or to 

 enter a small box which was then transferred to the larger one 

 and the animal was released. Food was given along all parts of 

 this runway and in the cage, and the animals were usually in their 

 normal state when in the experiment cage. 



The daily food was given at 2 :30 P. M. Enough was given 

 to keep the animals in good condition but not enough to satiate 

 them. The weekly menu, given under the experimenter's direction, 

 was as follows : 



Sunday. Bananas, yellow corn, sunflower seed. 



Monday. Boiled potatoes, bread, bananas. 



Tuesday. Roasted peanuts, bread, apples, 



Wednesday. Cabbage, lettuce, carrots, bread, bananas. 



Thursday. Boiled potatoes, bread, apples. 



Friday. Boiled rice with raisins, bananas. 



Saturday. Boiled potatoes, bread, dates. 



III. Method of Investigatiox. 

 1. Prohlem Method Used. — I have used in the investigation the 

 problem method only. The animals have been placed in the pres- 



