the door was simultaneous with the pulling of the thread by Oriole 1.
For the 87th test the strings were removed from the right and placed in the niche to the left of the door, place 2, Fig. 19. Oriole 2 was on the door and went thence to where string C used to be. Oriole 1 opened in his usual way by pulling the threads. In changing the outside strings to the left of the door I had, of course, intended to modify the box for Oriole 2. At any rate if we failed to get results on the readiness with which Oriole 2 could do as the female English Sparrow did in series A, we did get some slight indications of imitation of Oriole 2 by Oriole 1. It was very similar to the result obtained a little earlier in this series. In the following test there was likewise a single indication of imitation.
_Fig_17.jpg)
Fig. 17
Male Baltimore Oriole 2. He, during an earlier trial, flew to this post, slipped off, struck String C and opened the door. He is shown here continuing this wholly unnecessary action.
For the remainder of this series Oriole 1 continued to open the door. Oriole 2 to all appearances saw him, but as they began to moult badly I did not improve the mechanism as I did later for the Crows in order to compel just one method of gaining entrance to the box. It is probable that these Orioles, had the tests been continued, would have given much better evidence of the power of imitation.
Great interest naturally attaches itself to these tests for the reason that at least one popular writer on the Baltimore Oriole has found it capable of very remarkable performances. It is said to resort to measures distinctive of an adult human being in arranging supports for its nests and in the tying of knots in
