43G JOHN B. WATSON 



as are to be found in this article and in the one by Franken, on 

 the instincts and intelligence of the dog, reviewed last year in 

 the Journal of Animal Behavior. 



IMITATION 



Mam Dials. Shepherd (25) gives some experiments upon imi- 

 tation in raccoons. One of the animals had learned by the trial 

 and error method to walk up an inclined plane of poultry netting 

 1.5 m. in length and 25 cm. wide to a box where food could be 

 obtained. This animal was used as the "imitatee." Three other 

 animals tested separately were allowed to watch the imitatee 

 perform this feat. Since these animals repeatedly failed to 

 profit by watching the trained animal perform the act, Shep- 

 herd concludes that "inferential" imitation does not form a 

 part of the raccoon's mental equipment. 



HABIT FORMATION 



Amphibians. Schaeffer (22) finds that the three species of 

 frogs studied (R. clamata, R. sylvatica, R. virescens) learned to 

 avoid disagreeable objects, such as hairy caterpillars, in from 

 four to seven trials. These habits persisted for at least ten 

 days. Under the influence of punishment by the electric shock, 

 R. clamata learned to avoid earthworms treated with chemicals 

 in two trials. 



Those habits which are intimately connected with obtaining 

 food are acquired by these animals in a time which is directly 

 comparable with the acquisition of similar habits in higher 

 forms, e.g., chick, tern, monkey, etc. The frog has been placed 

 low in the scale of intelligence by other investigators. This is 

 due to the fact that the problems presented it hitherto have 

 called into play relatively few of its hereditary mechanisms. 

 Two or three pages are devoted to the fruitless task of dis- 

 cussing the psychic processes in the frog. 



Birds. Hunter (15) finds that the pigeon forms maze habits 

 as readily as other birds, but not so readily as the rat and the 

 squirrel. The maze habits are perfectly retained for four weeks. 

 Visual and kinaesthetic cues are used in the learning process. 

 Kinaesthesis does not play so important a role in the mental 

 life of the pigeon as in that of the rodents. Although no especial 

 tests were made upon audition, Hunter is in agreement with 



