THE ASSOCIATIVE PROCESSES IN ANIMALS. 83 



are accessible to the skeptical in a monograph entitled " Ani- 

 mal Intelligence, an Experimental Study of the Associative 

 Processes in Animals," Supplement No. 8 to the Psycholog- 

 ical Review. Let it suffice to repeat here the assertion 

 therein justified, that in forming these associations the animals 

 do not think about the food, box, or clawing, at all, and do not 

 ordinarily connect idea with idea in an associative train of 

 thought ; that the association is between a directly felt situation 

 and an impulse to act. In the association of ideas, ideas are 

 the essential elements ; in the animal sort of associations the 

 " impulse and act" is the essential. They are homologous, not 

 to our trains of thought, but to our feelings in learning to 

 swim, dive, play golf, etc. They are direct practical associa- 

 tions leading immediately to external acts. From them to 

 associations of ideas is a long step, longer and more important, 

 perhaps, than the step from the latter to logical thinking. 



It is hard to answer our next question "To what extent is 

 this way of learning by the formation of associations prevalent 

 throughout the animal kingdom?" For students of animal life 

 have not had this process clearly in mind and have not collected 

 data with definite reference to it. It will be remembered that 

 illustrations of it in the case of mammals, birds, and reptiles 

 have already been given. Experiments on one of the bony 

 fishes, Fundulus majalis, have demonstrated its presence there. 

 These fish try to get out of the sunlight into a shady corner. 

 If, then, you arrange their aquarium so that one end is shaded, 

 the rest sunny, put them in the sunny end, with some mechan- 

 ical obstacle between them and the shady end, and watch their 

 actions, you will find that their manner of dealing with the 

 situation in their twentieth trial is different from that in their 

 first, in just the same way that the chick's in the pen or the 

 kitten's in the box was different. They engage in fewer use- 

 less acts, perform the successful act much sooner, and so, of 

 course, get back to the shade much more quickly. Let the 

 fish, for example, be in an oblong aquarium ten inches deep. 

 I put a wire screen, which fits across the aquarium, in behind 

 the fish, who is now at the shady end, and move it down 

 toward the sunny end. The fish swims ahead of it, turning 



