The figures give the number of couplets correctly or incorrectly recalled out of 64. In the case of the interval of one day the figures are a tabulation of the III. test (twenty-one hours) of the _C_ set, which contained 16 series of 4 couplets each. The figures for the intervals of two, nine and sixteen days are a tabulation of the _B_ set, which also contained 16 series of 4 couplets each. _C_ denotes correct, _I_ incorrect. TABLE VIII. SHOWING GREATER PERMANENCE OF COUPLETS IN WHICH INDIRECT ASSOCIATIONS OCCURRED. Pure Material. Mixed Material. Days. One. Two. Nine. Sixteen. One. Two. Nine. Sixteen. C I C I C I C I C I C I C I C I _M._ 40 22 23 39 22 40 2 0 2 0 3 0 _Mo._ 36 22 31 27 29 29 6 0 6 0 5 1 _S._ 27 34 6 55 2 59 1 60 2 1 3 0 3 0 3 0 _Hu._ 35 22 16 45 5 56 4 57 6 1 3 0 3 0 3 0 _B._ 48 16 17 43 9 51 7 53 0 0 4 0 1 3 1 3 _Ho._ 37 15 17 30 13 36 3 46 10 2 9 6 8 7 7 8 Total: 147 87 132 217 83 268 66 285 18 4 27 6 23 10 21 12 P'c't.: 63 37 38 62 24 76 19 81 82 18 82 18 70 30 64 36 We see from the table that the likelihood of recalling couplets in which indirect associations did not occur in learning is 63 per cent. after one day, and that there is a diminution of 44 per cent. in the next fifteen days. The fall is greatest during the second day. On the other hand, the likelihood of recalling couplets in which indirect associations did occur is 82 per cent. after one day, and there is a diminution of only 18 per cent. during the next fifteen days. The fading is also much more gradual. It is evident, then, that in all investigations dealing with language material the factor of indirect associations--a largely accidental factor affecting varying amounts of the total material (in these six subjects from 3 per cent. to 23 per cent.) is by far the most influential of all the factors, and any investigations which have heretofore failed to isolate it are not conclusive as to other factors. The practical value of the foregoing investigation will be found in its bearing upon the acquisition of language. While it is by no means confined to the acquisition of the vocabulary of a _foreign_ language, but is also applicable to the acquisition of the vocabulary of the native language, it is the former bearing which is perhaps more obvious. If it is important that one become able as speedily as possible to grasp the meaning of foreign words, the results of the foregoing investigation indicate the method one should adopt. * * * * * MUTUAL INHIBITION OF MEMORY IMAGES. BY FREDERICK MEAKIN.