The experiment with the above object was performed on 77 boys and 61 girls in the sixth year class (11-12 years old) of Ako primary school for 4 months. The memory was examined with 10 series of vocabularies and 8 series of numbers. The following results were obtained. 1) The auditory memory of girls was generally superior to that of boys; it was especially the case with regard to memorising numbers. 2) The coefficient of recall increased with repetition, viz., the coefficient was greater at the second time of recalling than the first, the third time still greater. 3) There is some difference in the memory capacity of the two sexes; namely, girls showed greater ability in memorising numbers than vocabulary, but boys showed no remarkable difference in either. 4) The first and the last items in one series were more easily recollected than the intermediate ones and this was still true after the lapse of a long interval of time. Mistakes in order occurred more frequently in the middle of one series. 5) Mistakes due to transposition of items in the series were most frequent. 6) Forgetting was a less frequent cause of error than transposition, and the introduction of wrong words into a series, the least noticeable of all. 7) There appeared to be little correlation between the powers of the memory and the marks gained in lessons.