12 FREDERICK S. BREED 



On the basis of these and similar observations, it has been 

 asserted that a chick swallows water instinctively, but must 

 learn to drink by imitation or accident ; that is to say, the drink- 

 ing instinct requires supplementation. A passage from Bald- 

 win ' will illustrate: "In the case of the fowl's drinking, it 

 is not the mere fact that drinking and eating may differ in the 

 degree to w^hich the performance is congenital; the reports 

 seem to show that this varies in different fowl ; but that instincts 

 (in this case drinking) may be only half congenital, and may 

 have to be supplemented by imitation, accident, intelligence, 

 instruction, etc., in order to act, even when the actions are so 

 necessary to life that the creature w^ould certainly die if the 

 function were not performed. That is the interesting point." 



For the sake of clearness in the discussion of drinking, the 

 parts of the drinking complex must be more sharply distin- 

 guished. There is (i) the approach to the object, elicited evi- 

 dently by optical stimulation, (2) a sort of rhythmic movement 

 of mandibles and throat, which brings the object within the 

 mouth, and (3) the swallowing activity, which is evoked by 

 stimuli resulting from the contact of water with the mouth, 

 and which is marked by an elevating movement of the head 

 and neck. We find an exactly parallel series upon analysis 

 of the pecking reaction: (i) striking, (2) seizing, and (3) swal- 

 lowing. Any full account of the drinking instinct must include 

 the approach to the object as well as the subsequent manipu- 

 lation. 



No one, I think, will deny that the touch of w^ater in the 

 bill evokes reaction 3 of the above series. And we know that 

 chicks may get this appropriate contact-stimulus indirectly by 

 pecking. Furthermore, the drinking of one chick in the presence 

 of another often stimulates this other to become active about 

 the water and thereby leads to its drinking. That is, drinking 

 usually does begin as the result of a contact stimulation mediated 

 by the prior activity of the pecking and imitating instincts. 

 But this at once suggests the further question. Are imitating 

 and feeding necessary precursors to reaction i of the series, 

 the movement of approach ? The results of the foregoing experi- 

 ments seem to show clearly that the drinking instinct is self- 

 dependent in so far as its relation to these other instincts is 



'Baldwin, J. M.: Instinct. Science, N. S., 1896, vol. 3, p. 669. 



