Fractional Activity in Mammalian Reflex Phenomena. 143 



At the end of this experiment the remaining nerve twig of tenuissimus was 

 divided. Thereafter all reflex contraction was abolished and there were 

 48 fibres in the twig. Of these probably not more than 32 were motor. 



In this experiment, therefore, a number of motor fibres which probably did 

 not exceed 32 conditioned reflexly a number of different mechanical grades of 

 contraction which probably did not fall short of 50. 



