edge of the door. In the following trial Young Crow 1 opened in much the same indirect manner with the claws, but only after Jim had made thirty efforts with his bill. Again there were many efforts on the door, but this trial the young one pulled the strings as he should. This was followed by a test in which Jim made about fifteen unsuccessful efforts with his beak, but Young Crow 1 succeeded by striking through the wire at the left end of the latch. Previous to this I had changed the box so that no amount of pecking could open it, but now I had to cut off the end of the latch so that it did not extend out from the post to which the door was hung. From the fact that in the next trial this Young Crow 1 made many attempts on the door and front of the box, we infer that his records would give us a good curve of learning did he not alternate so much with Jim and were there not so many conditions necessary for Jim and tests for imitation, which were hardly calculated to permit of good results for the Young Crow 1 as a subject of mere learning tests.
From this point on to the close of these tests this Young Crow 1 opened the box except when he was fed just preceding each test and Jim was allowed to go hungry. Even then the former would sometimes be the first to perform the necessary act. See Fig. 23. This would indicate that his opening the box was often a result of what we might term his playful activity.
_Fig_23.jpg)
Fig. 23
Young Crow 1 shown opening the door by pulling String C in Place 5. The Old Crow was induced later to work in this place, but did so in his own way. The Young Crow was fed from the hand just before each test and as a rule made no attempts to open the box.
It is of interest to note that when Jim made a rapid but un-
