which promised to cause such acts to become rapidly imitation of a reflective, voluntary or intentional kind. As they first occurred they were to me examples of intelligent imitations, prepared for by the child's own experience.
It may not be amiss to ask what it is which characterizes those acts which adult persons imitate in an unreflective way? Does the preparation we have had, the previous experience, have the same effect as we think it has for these birds, only for the latter in a far more restricted manner?
There are, then, many reasons for believing that it is possible by giving a bird previous experience with the object to be worked with to get that sort of imitation which may be called intelligent. This probably is on a little higher level than instinctive, and yet does not mean the same as reflective, intentional, or voluntary. The writer hastens to say, however, that he really believes that any classification of the above kind does not adequately represent the facts. The observed facts in the animal are of all stages of instinctive and intelligent and in the child these two are not left behind when they emerge into the reflective. In this instinctive basis we find a satisfactory explanation of the facts concerning imitation in bird songs. There is probably no distinction to be made here between that which is instinctive from that which is intelligent. Were it possible to come to the bird with an act for it to imitate, which would appeal as natural, spontaneously and repeatedly as these call notes and songs do, then we should probably get intelligent imitation as unmistakably and easily. This is difficult, but the writer feels that with the long series of tests under the conditions imposed and the demands of the more difficult criterion, we may be more certain of getting examples of intelligent imitation; but hardly that which is distinctively human, the reflective, intentional or voluntary.
VIII. Summary
1. Several long additional series of experiments on the intelligence of the English Sparrow and Cowbird have been obtained. The rate of learning is slower than that found earlier, but my present conditions were different inasmuch as the primary object here was to get results on imitation. This should be kept in mind by the reader in connection with all the tests here described. The Cowbirds spent much of their time in looking for parasites on the Sparrows and parts of the cage.
2. The male English Sparrow showed signs of imitating the female Sparrow, and more unmistakable signs of imitating the Cowbird. His latest change in behavior satisfied the requirements of the criterion which the writer from previous
