TABLE I. TIME REQUIRED TO REACH FOOD IN LABYRINTH L

Animals
Trials,
1 daily.		ABCDEFAverage
' "' "' "' "' "' "' "
11)28:50:5942:2049:0422:134:0424:35
2)7:22:2225:4710:17:482:027:46
3)1:18:128:2912:35:121:414:05
4):32:2110:511:26:19:522:24
5):24:282:362:18:121:331:15
6):25:261:10:55:121:50:50
7):15:24:28:32:152:09:41
8)1:05:23:331:19:171:46:54
9):16:24:57:58:10:26:32
10):24:321:15:512:12:31:58
11):12:211:40:30:17:54:39
12):16:32:491:34:221:18:49
13):13:182:30:18:10:42:42
14):29:32:27:31:25:36:30
15)1:00:24:30:31:12:35:32
16):19:521:10:22:17:24:34
17):14:14:31:39:13:57:28
218):13:09:29:13:16:29:18
19):10:10:36:26:07:14:17
20):11:15:34:17:07:10:16
21):13:14:34:16:09:21:18
22):09:16:26:14:08:11:14
323):12:421:29:395:53:131:31
24):20:171:31:33:15:13:31
25):15:24:40:28:19:20:24
426)1:2116:291:2213:543:511:366:26
27)3:364:45:441:031:092:592:23
28):511:24:461:04:561:091:02
29):51:411:10:402:17:11:58
30)2:04:18:41:14:07:19:37
531):08:33:25 :07:07:16
632):09:15:20 :08:31:17

1: With 18-candle-power illumination of the room.

2: Same illumination; tests given after the animals had heard four other pigeons pecking in the labyrinth.

3: With 2-candle-power illumination, other conditions the same.

4: With a slight illumination through single curtain, other conditions the same.

5: After two weeks' rest, conditions as in 2.

6: After six weeks' rest, conditions as before.

Let us now notice the gradual progress of learning in three important parts of the maze, as shown in Fig. 2. It will be seen that in the beginning the animals started upon their usual course and pressed against the first partition (stage 1), but that later they touched it less and less (stages 2 and 3), and that finally they avoided it entirely (stage 4). The adjustment here was fairly simple: the sound made by the opening of the entrance door, and the glimpse thus given of the labyrinth, gradually came to be conditions of the movements of turning to the left, on emerging from the entrance, and passing along the compartment toward the opening, where impressions, mostly visual, in the same manner determined the movements of turning to the right and entering compartment 2.

The blind alley was naturally a decided obstacle. The pigeons learned to avoid this compartment by going around it only after many unsuccessful attempts to go through it. During the first test the animals entered it many times (stage 1); on emerging they returned to the second or the first compartment, only to encounter the pen again when they re-advanced toward the food; finally, on reëmerging from the annoying enclosure, perhaps for the eighth or tenth time, they might happen to turn to the right instead of going forward as usual toward the entrance of the box, and thus make their way along the new passage and reach the food. For the next few tests they usually entered the blind alley, but less frequently, and they remained for shorter periods (stages 2-4). Later they merely entered (stage 5); and still later they passed very near the opening without entering, or only paused a moment before it (stage 6); and finally they passed it without the slightest hesitation, walking briskly, but with well-directed movements, midway between the partitions (stages 7-8). The act of turning seemed to be an especially important factor in this habit. We notice that it was a turn to the right (most probably accidental) which first enabled the animals to get beyond the opening of the blind alley; that this same act was repeated in each successive trial until, by the gradual shortening of the loop forming the path taken by the animals in passing into, and from, the labyrinth it was finally reduced to a mere pause (stage 6); and that this later disappeared entirely, leaving only the left turn, which instead was now conditioned by the visual data at that part of the labyrinth and carried the animal past the entrance of the blind alley.

FIG. 2. Stages in learning Labyrinth L. The curves indicate the pigeon's horizontal movements. Pauses are represented by heavy dots.

The animals did not come in contact with the second partition until they had almost learned to pass the opening of the blind alley (see stage 6). This was probably because the turn to the left which was made on approaching x was associated with visual data derived from points farther along the course (y), and when the animals reached z, compartment 2, these same data were received and were sufficient to occasion the turn to the left there also, thus bringing the birds against the partition. The adjustment was made principally on the basis of new sense-data arising from running against the wire, looking at it more closely, etc. For a few trials the birds made the turn at x too quickly, and thus failed to reach the third compartment. One of my most intelligent subjects made this mistake in the third test, and again in the sixth and seventh, and retained the act almost unchanged through the tenth, eleventh, twelfth, thirteenth, fourteenth, sixteenth, seventeenth, twentieth, and twenty-first tests, so strong was the tendency to continue a movement once begun, though it was really disadvantageous.[200]

FIG 3. Labyrinth M. E, entrance; F, food-box; height of large box and width of passages the same as in Labyrinth L.

After reaching the food and satisfying their hunger, the animals often returned to the maze passages, seeking an exit; but they never "explored" passages or showed other evidence of "free curiosity" and "desire to know all their new surroundings," as Small reports concerning rats.[201]

B. Habits in Labyrinth M

Five of the animals previously used were next tested twice daily, forenoon and afternoon, for five days, in a larger, more complicated maze. It had two blind alleys, and the food-box was near the centre (see Fig. 3). The animals' general behavior was similar to that before observed. The periods are given in Table II.