2.6 



THE QUARTERLY REVIEW OF BIOLOGY 



although not when it was placed up on 

 edge. The brush was also avoided when 

 the stiff fibres were upturned and likely 

 to irritate his nose, but was picked up 

 readily enough when turned the opposite 

 way. Strict control of this factor was 

 not possible at the time, otherwise we 

 feel the results of the test would have 

 been more satisfactory. 



The results here presented need to be 

 greatly supplemented and the testing of 

 Fellow extended in several directions be- 

 fore a true evaluation of the dog's ability 

 can be arrived at. However, there would 

 seem to be no doubt that scores of associ- 

 ations between verbal stimuli and definite 

 responses have been well fixated by the 

 patient teaching of Mr. Herbert during 

 the past several years. The evidence for 

 associations between verbal stimuli and 

 objects or places would doubtless be 

 forthcoming if a test were arranged in 

 which object-discrimination could be 

 made without the element of delay be- 

 tween stimulus and response entering in. 

 We hesitate to make an interpretation of 

 the present findings in terms of the dog's 



capacity for making a delayed reaction, 

 on account of the meagreness and incon- 

 clusiveness of the data. In the type II 

 command, which really includes the 

 retrieving-objects test, we have a delayed 

 reaction in which the essential signal for 

 response is an auditory associate of the 

 object, or locality in space, in connection 

 with which the response must occur. 

 Since the auditory stimulus gives no clue 

 as to the localization of the object or 

 place, orientation cannot be had as in the 

 usual delayed reaction situation by the 

 maintenance of gross bodily attitudes. 

 If further tests should reveal certain evi- 

 dence of such ability, as is more than 

 suggested by the results here reported, 

 then the dog would merit a much higher 

 rank in the scale of mental evolution 

 than most of us have been willing to ac- 

 cord him in the past. . 



This paper was read by the senior author 

 before the Galton Society, Museum of 

 Natural History, New York City, in 

 connection with a demonstration of 

 Fellow by Mr. Herbert before the Society 

 on Friday, December 2., 19x7. 



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