S. O. MAST AXD L. C. PUSCH. 



trials. Amoeba F made no contacts until trial 8; between trials 

 8 and 15 there were 8 contacts, while in the remaining 12 trials 

 there was but one contact. There was one contact in the first 

 trial of Amoeba G, then none until the 7th, when a reversal began 

 and persisted very generally through the iyth, by which time 

 23 contacts had been made; in the remaining ten trials there 

 were 8 contacts. 



TABLE I. 



RESPONSE OF AMCEBA TO CONTACT WITH A HIGHLY ILLUMINATED REGION IN 



THE FIELD. 



The totals by groups of three consecutive trials fluctuate 

 between 18 for the first group, 12 for the middle and 6 for the 

 last. In other words there is a modification of response in the 

 sense that the number of attempts to continue in the original 

 direction after meeting the light decreases in general as the 

 number of trials of the series increases. 



