356 H. M. JOHNSON 



TABLE 2— Continued 



oS o 



•9 tj cS Remarks 



3 £ 3 



9 



6 Responses slow ; ate little. 



" 30 0.195 10 9 



" 30 0.190 10 9 



" 31 0.185 10 9 



" 31 0.181 10 10 



June 1 0.177 20 15 



" 2 0.173 10 10 



" 2 0.169 10 10 



" 2 0.169 10 10 



3 0.166 10 8 



3 0.163 10 6 



3 0.260 10 9 



4 0.260 5 5 



4 0.163 10 7 Taken as threshold; subtends 57" of V. A. 



4 0.160 10 6 



TABLE 3 

 Record of Chick 1 



O a) o 



n P 1- ^ >-i 



Date S u -2 « -2 £ 8 Remarks 



^^ zB I" 





Dec. 17 2 . 230 10 4 In general room illumination. 



"18 2 . 230 10 4 Very light charge on punishment grills. 



" 19 2 230 10 3 



" 20 2.230 10 5 Learned to leap from charged grill into entrance 



of food boxes. 



" 21 2.230 10 4 Additional grill placed in entrances to food boxes. 



■ 22 2.230 10 2 



" 24 2.230 10 6 Preference for Rib; not worked previous day. 



"25 2 . 230 10 4 Tendency to choose in rhythmic alternation. 



"26 2 . 230 10 5 Tests discontinued until January 7. 



Jan. 7 2.230 10 5 This and succeeding series in darkness. No 



punishment. 



" 8 2.230 10 5 Preference for Rib; very slow, no punishment. 



" 9 2.230 10 7 Preference for Rfb; no punishment. 



" 10 2.230 10 7 No punishment. 



" 11 2.230 10 5 Preference for Rfb; no punishment. 



"12 2 . 230 10 4 Light charge on punishment grills. 



" 13 2.230 10 5 Charge increased; no effect. 



" 14 2.230 10 4 Very much slower; tendency to stand on charged 



grill. 



" 15 2.230 10 3 Responses very slow; charge reduced. 



" 17 2.230 10 4 Invariably choice of Rfb. 



" 18 2.230 10 3 Preference for Rfb. 



"19 2 . 230 10 7 Position habit interrupted by punishment. 



" 20 2.230 10 3 Very slow. 



" 21 2.230 10 8 



