The object of these experiments, stated in general terms, was to study the kind and the degree of transfer of training in white rats which were allowed to learn a maze after they had learned, either completely or partially, one or more other mazes. Specifically, the object was to find out:<br><br>1. Whether there was transfer of training between a pair of mazes which were learned completely one after the other, and if so whether it was positive or negative. These expressions, "positive transfer" and "negative transfer," are familiar to those interested in this phase of psychological research; but it may not be useless to remark, for the sake of some chance reader, that by the former is meant that the mastery of one or more mazes renders easier the mastery of a subsequent one, while by the latter is meant that the mastery of one or more mazes renders more difficult the mastery of a subsequent one.<br><br>2. Whether, if either positive or negative transfer is present, it will persist through a series of mazes; and whether, if both present and persistent, it will also be cumulative.<br><br>3. The effect upon the learning of a maze of having partially learned a preceding maze.<br><br>4. The effect of the complete learning of a maze upon the mastery of another maze already partially learned.<br><br>5. Whether it is more advantageous to learn two mazes in succession; or to partially learn one, then completely learn the other, and finally perfect the learning of the former.<br><br>6. The effect upon the relearning of a maze of having learned four intervening mazes between the original learning of the maze and its relearning.<br><br>Diagrams of the mazes are presented in Plate I, figs. 1-5.