on the floor. See Fig. 9. These would seem to be modifications of his two earlier methods. One might reasonably infer that such variants were due to the example he had had in the behavior of the Cowbird. It should be added, however, that my notes describe the efforts of the two birds in a different manner. Those of the Cowbird are designated as "mumbles
![](http://upload.wikimedia.org/wikipedia/commons/thumb/3/3e/American_Journal_of_Psychology_%28Volume_21%29_Fig_8.jpg/300px-American_Journal_of_Psychology_%28Volume_21%29_Fig_8.jpg)
Fig. 8
The female Cowbird as she opened the door with the beak. This is a very simple way of opening the door. As a rule the male English Sparrow made many attempts before the Cowbird left the perch.
![](http://upload.wikimedia.org/wikipedia/commons/thumb/0/05/American_Journal_of_Psychology_%28Volume_21%29_Fig_9.jpg/300px-American_Journal_of_Psychology_%28Volume_21%29_Fig_9.jpg)
Fig. 9
The male English Sparrow as he opened the door following the times when the Cowbird had used her method shown in Fig. 8. He had been flying out from the top and alighting on the strings.