286 FURNESS: OBSERVATIONS ON THE MENTALITY OF 



vinced ; they were tested with dupHcate keys placed on different key 

 rings and the right key was always selected — two of the keys were 

 for Yale locks and hard to distinguish. On one occasion when I 

 took Mimi, the chimpanzee, as a demonstration to one of the classes 

 in psychology at the university she surveyed the audience assembling, 

 possibly 125 m.en and women, with great interest while sitting 

 quietly in a chair in the amphitheatre ; as a group of four or five 

 people entered at a door on the side, she turned her eyes toward 

 them. In the group was one who had been her devoted doctor and 

 nurse during her severe attack of pneumonia four years previously. 

 She had not seen him since her recovery. The instant she caught 

 sight of him she jumped from her chair, rushed to him, threw her 

 arms around his neck, putting her face close to his and giving her 

 shout of greeting. It was too marked a demonstration of aft'ection 

 to be anything short of actual recognition. There are, however, as 

 we all know, many instances of quite as remarkable feats of memory 

 as this among dogs and horses and possibly cats. 



After an absence of six months I have found that my apes have 

 forgotten nothing that I have taught them, although during my ab- 

 sence their course of instruction ceased entirely and they refused 

 to do for others what I had taught them. Both the orang-utan and 

 the chimpanzee have been able to learn the letters of the alphabet in 

 order up to M. This is merely a demonstration of memory for dif- 

 ferent shapes in a certain sequence ; the letters which I used are cut 

 out of wood ^ inch thick by four inches square. The chimpanzee 

 recollects quite accurately just the sequence of these shapes in the 

 series. By name she does not distinguish them as well, except where 

 the letter sound is very distinct : B, F, H, L, M, seem to be easy for 

 her to recognize whereas A, K, E, D, C, G, are confusing. When 

 asked for the letter / she is apt to mistake it for her eye to which she 

 points. When the letters are drawn the same size and width with 

 chalk on a blackboard or printed in black on white cards she fails 

 to recognize them. To test her ability to compare shape and size I 

 have used an ordinary form-board consisting of ten differently 

 shaped blocks about half an inch thick and a board wherein are cut 

 ten hollows corresponding in size and shape to the blocks. The 

 hollows are about ^ inch deep and to make them more easily seen 



