28 . G. V. HAMILTON 



experimenter than to the apparatus. The detailed record of her 

 reactions, which is given in the appendix, shows lapses from 

 periods during which she quite obviously reacted with refer- 

 ence to the one-impossible-alley principle into periods of grossly 

 inadequate behavior. During one of her lapses she was almost 

 exclusively attentive to her clothing, and after her day's trials 

 were over she wept, declaring that she felt humiliated to have 

 appeared before me so unattractively clad. Girl 9, with 12 

 E-reactions, is a five-year old Italian. She is excitable, inor- 

 dinately distractible and a favorite among the other children 

 and the teachers on account of her merry ways. It was im- 

 possible to make her take the experiments seriously. 



Monkey 5, with 18-E reactions, and Monkey 26, with 30 E- 

 reactions, have already been discussed as atypical animals. In 

 my earlier studies five monkeys gave an average of 4.8 E-reac- 

 tions per 100 trials, hence the records of Baboon 2 and Monkeys 

 16 and 18 of these studies (an average of 6 E-reactions per first 

 100 trials) may be taken as fairly typical in this respect. It 

 is important for subsequent discussions of the determinants of 

 D and E-reactions that only three of the 25 human and infra- 

 human primate subjects of these studies (Girl 9 and atypical 

 Monkeys 5 and 26) have individual records of E-reactions which 

 equal or exceed that of the rodent subject which has the mini- 

 mum number of such reactions for the entire group of 24 rodents. 

 It is clear that primitiveness of reactive equipment favors the 

 manifestation of E-reactions. 



Although the various rodent species have records which dis- 

 close marked individual differences, both the table of averages 

 of E-reactions (table 7) and the table of individual reactions 

 (table 2) support the view that in the presence of a situation 

 for which they have no specifically adaptive instinct these sub- 

 jects have, without exception, a marked tendency toward the 

 repetition of unsuccessful as well as of successful attempts at 

 adjustment. The high average of E-reactions for gophers (45.80 

 E-reactions per 100 trials) is consistent with my observations 

 of the field and cage behavior of these animals. I have a small 

 experimental garden, in one part of which a gopher persistently 

 attacked the roots of a loganberry vine. One of the numerous 

 mouths of his network of burrows was close to a hydrant, so 

 that I was able to turn water into it without much trouble to 



