306 HARVEY CARR 



five suggested hypotheses as to the relation between vision and 

 adaptation, two are disproven by the experimental data. Three 

 possibilities remain. Adaptation may be a further process of 

 automatization and rats with vision are at an advantage because 

 of their greater learning capacity. Adaptation can not be ex- 

 plained wholly in terms of this conception as the adaptive 

 capacity of the various groups of animals is not proportional 

 to their relative learning ability. Visual adaptation may be a 

 process of decreasing sensor}-' susceptibility to the distractive 

 stimuli. This conception can not wholly explain the phenome- 

 non as certain facts indicate that vision can correct for dis- 

 turbances mediated through other sensory avenues. Unaltered 

 or familiar visual stimuli exert a quieting and reassuring effect 

 upon the organism and enable it to resist the distractive effects 

 of other stimuli. There are no facts which can not be explained 

 fairly successfully on the basis of this hypothesis. 



The maze act and the learning process are much more compli- 

 cated phenomena than the conclusions of some previous inves- 

 tigators would indicate. The habit does not consist merely of 

 tactual, kinaesthetic and motor elements. Other accessory and 

 conditioning components are also present. Learning does not 

 consist merely of the organization of certain tactual and kinaes- 

 thetic stimuli with certain movements. Many other sensory 

 factors are present which release their quota of impulses that 

 must be harmoniously integrated and organized in some fashion 

 adapted to the solution of the problem. 



All statements as to the functions of smell, vision, or other 

 senses must be interpreted as applying only to the situations 

 obtaining in these experiments. 



