| Choices of all 6 boxes when food was placed in red, yellow, green, or blue boxes | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Food in Red Box | Food in Yellow Box | |||||||||||
| Animals | R, | Y, | G, | B, | B'k. | G'y. | R, | Y, | G, | B, | B'k, | G'y. |
| (B) | 12 | 6 | 7 | 3 | 2 | 0 | 2 | 12 | 6 | 7 | 0 | 3 |
| (C) | 15 | 8 | 1 | 4 | 2 | 0 | 3 | 12 | 1 | 6 | 3 | 5 |
| (E) | 11 | 8 | 5 | 3 | 3 | 0 | 3 | 10 | 5 | 3 | 5 | 4 |
| (F) | 7 | 5 | 9 | 6 | 2 | 1 | 6 | 6 | 5 | 6 | 3 | 4 |
| (G) | 9 | 1 | 7 | 5 | 3 | 5 | 5 | 11 | 6 | 3 | 2 | 3 |
| (H) | 13 | 3 | 5 | 3 | 3 | 3 | 5 | 9 | 6 | 3 | 3 | 4 |
| (I) | 11 | 5 | 2 | 4 | 6 | 2 | 4 | 10 | 5 | 4 | 3 | 4 |
| (J) | 10 | 0 | 6 | 8 | 4 | 2 | 5 | 10 | 3 | 3 | 5 | 4 |
| Total, | 88 | 36 | 42 | 36 | 25 | 13 | 33 | 80 | 37 | 35 | 24 | 31 |
| Food in Green Box | Food in Blue Box | |||||||||||
| Animals | R, | Y, | G, | B, | B'k, | G'y. | R, | Y, | G, | B, | B'k, | G'y. |
| (B) | 4 | 5 | 12 | 4 | 5 | 0 | 1 | 3 | 5 | 10 | 6 | 5 |
| (C) | 3 | 4 | 14 | 5 | 1 | 3 | 3 | 1 | 2 | 13 | 2 | 9 |
| (E) | 1 | 9 | 7 | 11 | 0 | 2 | 3 | 5 | 5 | 10 | 3 | 4 |
| (F) | 0 | 8 | 9 | 6 | 0 | 7 | 0 | 3 | 6 | 11 | 5 | 5 |
| (G) | 2 | 5 | 16 | 2 | 4 | 1 | 5 | 5 | 4 | 5 | 4 | 7 |
| (H) | 1 | 3 | 15 | 5 | 6 | 0 | 7 | 5 | 5 | 6 | 4 | 3 |
| (I) | 0 | 4 | 15 | 6 | 2 | 3 | 5 | 5 | 3 | 9 | 5 | 3 |
| (J) | 4 | 1 | 12 | 9 | 1 | 3 | 6 | 4 | 4 | 7 | 5 | 4 |
| Total, | 15 | 39 | 100 | 48 | 19 | 19 | 30 | 31 | 34 | 71 | 34 | 40 |
TABLE VIII. COLOR ASSOCIATION. DISTRIBUTION OF RIGHT CHOICES
| Choices from series 1 to series 5 in the case of red, yellow, green, and blue boxes | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Red Box | Yellow Box | |||||||||
| Animals | 1, | 2, | 3, | 4, | 5, | 1, | 2, | 3, | 4, | 5, |
| (B) | 0 | 1 | 2 | 4 | 5 | 1 | 2 | 3 | 2 | 4 |
| (C) | 2 | 2 | 4 | 3 | 4 | 1 | 2 | 3 | 3 | 3 |
| (E) | 2 | 1 | 2 | 3 | 3 | 1 | 0 | 3 | 2 | 4 |
| (F) | 0 | 1 | 1 | 2 | 3 | 0 | 2 | 2 | 1 | 1 |
| (G) | 0 | 2 | 3 | 2 | 2 | 2 | 2 | 1 | 3 | 3 |
| (H) | 1 | 1 | 3 | 4 | 4 | 0 | 2 | 2 | 2 | 3 |
| (I) | 1 | 2 | 3 | 3 | 2 | 1 | 2 | 2 | 3 | 2 |
| (J) | 1 | 2 | 2 | 2 | 3 | 1 | 2 | 1 | 2 | 4 |
| Total, | 7 | 12 | 20 | 23 | 26 | 7 | 14 | 17 | 18 | 24 |
| Green Box | Blue Box | |||||||||
| Animals | 1, | 2, | 3, | 4, | 5, | 1, | 2, | 3, | 4, | 5, |
| (B) | 1 | 2 | 2 | 4 | 3 | 1 | 3 | 1 | 2 | 3 |
| (C) | 3 | 2 | 3 | 4 | 2 | 3 | 2 | 2 | 3 | 3 |
| (E) | 0 | 1 | 1 | 1 | 4 | 0 | 1 | 3 | 2 | 4 |
| (F) | 0 | 1 | 2 | 3 | 3 | 1 | 1 | 2 | 4 | 3 |
| (G) | 2 | 4 | 3 | 3 | 4 | 1 | 1 | 0 | 0 | 3 |
| (H) | 2 | 3 | 4 | 3 | 3 | 0 | 1 | 2 | 2 | 1 |
| (I) | 1 | 3 | 3 | 3 | 4 | 0 | 2 | 2 | 3 | 2 |
| (J) | 1 | 1 | 3 | 3 | 4 | 1 | 2 | 1 | 1 | 2 |
| Total, | 10 | 17 | 21 | 24 | 28 | 7 | 13 | 13 | 17 | 21 |
There is no evidence that the color-preference of the animals assisted them in choosing correctly, in fact, they were rather less successful in dealing with those colors for which they had previously shown decided preference,[212] since the whole number of right choices was less in the case of the green and blue boxes (85) than in the case of the red and yellow ones (92), and since there was a relative diminution in the rate of learning toward the last in case of the former boxes.[213]
To test the animals' ability to discriminate shades of colors in finding their food, two birds were used, with four boxes, each covered with a different shade of red paper, and two with the boxes covered with green paper. The brightness of the different shades was not measured, but to the eye it seemed to be equal in each of the cases. The food was placed in the box having the most nearly saturated color, and twenty-four trials in series of six, as before, were given each bird. The results were quite similar to those secured with different colors. With the red shades there were twenty-two choices of the best saturated shade to eight, ten, and eight, respectively, of the other three; and with green, twenty-one to nine, ten, and eight. The 43 correct choices were distributed from series 1 to series 4 as follows: 7, 11, 12, and 13, which shows learning as before. The relatively large number of right choices was probably due, partially to the fact that fewer alternative choices were possible since only four boxes were used, instead of six, and partially to the fact that the box containing the food may have been slightly brighter than the others.
Throughout these trials the position-element was a decidedly disturbing factor. When the animals were first learning to choose a box of a definite color, some would show a marked tendency to approach a receptacle occupying a certain position, and would persist in this from series to series. Others at first showed no special preference for certain positions, but, after happening to make a correct choice, they would return to that same place the next time, and thus miss the right box which had been changed for the new test.
C. Form Tests.
In this experiment the six food-boxes were each of different form: triangular, square, oblong, hexagonal, circular, and elliptical. They were of the same capacity, and were covered with light-brown paper. As in the preceding experiment, the birds were tested for only four of the boxes, and were given thirty trials each. Six animals were used, and as they were not the same as those previously employed, the square box (which had always been used before) had no advantage over the others in attracting the birds at the beginning of the trials. The tests were given as in the preceding experiment, except that it did not seem necessary to change the position of each of the six forms before giving each test; it was thought sufficient to move the food-box, and, if a wrong choice had been made in the preceding test, also the box wrongly chosen. The results are shown in Tables IX and X.