76 CHARLES A. COBURN AND ROBERT M. YERKES 



to the accumulation of additional facts concerning the natural 

 history, instincts, and general habits of the birds. 



On June 7th, 1914, three young crows were captured near 

 the Station. These birds were about ready to leave the nest. 

 One, indeed, was taken from a limb beside the nest. This indi- 

 vidual from the first exhibited fear and was so troublesome 

 that after two days it was discarded and the remaining two 

 birds w T ere kept for observation. They were placed in a box 

 which was frequently passed by human beings, and were several 

 times a day fed by hand, being allowed to come out of the box 

 at will and become thoroughly accustomed to the experimenters. 

 From the time of capture they were perfectly tame, ate readily, 

 and the characteristic fear reactions never appeared. When 

 taken from the nest, they were probably at least six weeks old. 



Throughout this report, these birds will be referred to as 

 number 3 and number 4. Number 3 was from the first the 

 larger of the two and the less timid. It, during the several 

 months of observation, always came to us, perching on arms, 

 shoulder, or head, as it had opportunity, and showing a friendly 

 interest which was apparently somewhat independent of its 

 desire foi food. It evidently liked to be petted. Our assumption 

 is that this bird is a male. 3 Number 4, by contrast, was smaller, 

 shyer, more wary, and after a few weeks ceased to come to either 

 of us, except as drawn by hunger, and even then it often hesi- 

 tated to perch upon the hand or arm. In all probability, it is 

 a female. It has eaten less than number 3, and has been 

 considerably more difficult to experiment with. Usually, in the 

 course of an experiment, if the birds were in competition, number 

 4 would stand aside for number 3. 



Our additional experience with crows during the present season 

 but emphasizes our conviction that they are among the most 

 interesting of birds, and that their behavior is in every respect 

 worthy of careful analytic study. With respect to what we 

 shall term "ideational behavior," they have fallen short of our 

 expectations, for in the light of their varied interests, ingenuity, 

 curiosity, ceaseless activity, and apparent insight into simple 

 situations, we had assumed that they possess an intelligence 

 equal to that of many of the more intelligent mammals. The 



3 Since this was written, dissection has definitely established our surmise in the 

 case of both birds. 



