The series of the _B_ set were four couplets long. Each series contained one three-letter, one four-letter, one five-letter, and one six-letter nonsense word. The position in the series occupied by each kind was constantly varied. In all other respects the same principles were followed in constructing the _B_ set as were observed in the _A_ set with the following substitutions: No two foreign symbols of a series and no two terms of a couplet contained the same sounded vowel in accented syllables. The rule for the avoidance of alliteration, rhyme, and assonance was extended to the foreign symbols, and to the two terms of a couplet. The English pronounciation was used in the nonsense words. The subjects were not informed what the nonsense words were. They were called foreign words. Free body movements were used in the movement series as in the _A_ set. Rarely an object was involved, _e.g._, the table on which the subject wrote. The movements were demonstrated to the subject in advance of learning, as in the _A_ set. The following are typical _B_ series: B2. Nonsense words and objects. quaro rudv xem lihkez lid cent starch thorn B3. Nonsense words and verbs. dalbva fomso bloi kyvi poke limp hug eat B4. Nonsense words and movements. ohv wecolu uxpa haymj gnash cross frown twist The time conditions for presenting a series remained practically the same. In learning, the series was shown three times as before. The interval between learning and testing was shortened to 4 seconds, and in the test the post-term interval of _A^{13-16}_ retained (6 secs.). This allowed the subject 9 secs. for recalling and writing each term. The only important change was an extension of the number of tests from two to four. The third test was one week after the second, and the fourth one week after the third. In these tests the familiar word was always the term required, as in _A^{1-4}_, on account of the difficulty of dealing statistically with the nonsense words. The intervals for testing permanence in the _B_ set may be most easily understood by giving the time record of one subject. TIME RECORD OF _Hu_. Series. Im. Rec. Two Days. Nine Days. Sixteen Days. B^{1-4} Feb. 12 Feb. 14 Feb. 21 Feb. 28 B^{5-8} Feb. 19 Feb. 21 Feb. 28 Mch. 7 B^{9-12} Feb. 26 Feb. 28 Mch. 7 Mch. 14 B^{13-16} Mch. 5 Mch. 7 Mch. 14 Mch. 21