HABIT FORMATION AND FEELING QUALITIES 279 



No card could be located more than nine times in plan I dur- 

 ing any given period, since there were only nine subjects. It 

 will be recalled that subject H required 19 trials to make a per- 

 fect map. If all subjects had required that number of periods 

 it is possible that some of the cards would have been located 

 nine times nineteen, or 171 times. Table 4 shows in the last 

 column but one the number of times each card would have been 

 located had all the subjects continued charting from the time of 

 its location until H completed his in the nineteenth period. The 

 last right hand column shows the percentage of this number (for 

 each card) to the possible number of locations. For example, 

 the 4 of C under the assumed conditions would have been located 

 164 times, that is 95.9 per cent of 171, the highest possible num- 

 ber of times. The cards were then arranged in a descending 

 series, beginning with the 4 of C and ending with the 5 of H 

 which had been located 105 times, or 61 per cent of the possible 

 number. This serial arrangement shows that eighteen peripheral 

 cards, with the exception of the 9 of C and the Q of H, two inside 

 cards, were given the highest number of locations. 



The peripheral cards of the case were located in the following 

 order: upper left, upper right, and lower right. The lower 

 left, 8 of D (plan I), ranks ninth. The subjects regarded lower 

 left hand boxes difficult to remember: (1) The boxes seldom came 

 within range of the visual field, (2) This particular box 8 of D 

 (diagram 1) was reached by an awkward movement down 

 vertical with the right arm passing across and in front of the 

 body, (3) The 8 of D box received a card requiring substitution, 

 8 of S (diagram 2; plan 1 first 13). Edge boxes rank next to 

 those on the corner of the case: their nearness to the corner 

 boxes, and their conspicuous position they have roughly 25 

 per cent less distraction than the inner boxes seem to account 

 for their priority over the central boxes. These reasons appear 

 to suffice when outer boxes are compared with inner, but they 

 do not explain priority of one edge-box over another. A bit 

 of objective evidence mentioned above is repeated here to intro- 

 duce principles to be more rigidly applied and tested in connec- 

 tion with the problems of inhibition, error and feeling tone. (1) 



