348 



ROBERT M. YERKfcs 



then turned to the right again and moved directly and rapidly 



into the lube. 



TABLE 7 



Results of Experiments After Removal of Brain on April 30 



Sand- Sand- 



Date Trial paper Shock Time Dale Trial paper Shock Time 



May 2 861 5 501" May 21 896 1 327" 



897 

 898 

 899 



900 



Av. of five t rials 



May 28 901 

 902 

 903 

 904 

 905 



Av. of five trials 



June 



916 

 917 

 918 

 919 

 920 



Av. of five trials 



.6 



May 29 900 4 



907 



908 



909 



910 



Av. of five trials .8 



June 6 911 



912 2 



913 



914 



915 



Av. of five trials .4 



73" 



55" 



76" 



117" 



129.6" 



300" 



72" 

 91" 

 48" 

 53" 



112.8' 



355" 

 64" 

 57" 

 39" 

 60" 



.4 115" 



430" 



185" 



77" 



65" 



54" 



162.2" 



442" 

 52" 

 47" 

 45" 

 60" 



.2 129.2" 



Trial 871, given at 10:45 on ^ a Y 6, five and one-half days 

 after the operation exhibited precisely the kind of behavior 

 that the experimenter had expected of the "brainless" worm. 

 The subject, with its conspicuous "plug" of regenerating tissue, 

 moved forward readily, but reversed whenever an obstacle was 

 encountered. It wandered about a great deal, as if lost. Finally, 

 it touched the electrodes, received the shock, and reacted vio- 

 lently by "springing back" to the middle of the T. It then 



