162 University of California Publications in Zoology. [Vol. 4 



On the third day (July 26), the starfish as soon as it was 

 placed on its back took hold with b and c. But as it was left 

 free, the ray a also took hold; c was released, and the starfish 

 turned on a and b. There was still much awkwardness in turn- 

 ing on b and c; the ten lessons of this day were devoted to prac- 

 tice in this. 



The same difficulty appeared on the fourth day, July 27. 

 The rays b and c took hold readily, but in an uncoordinated way. 

 Much time was spent by the experimenter in inducing them to 

 take hold properly, releasing the wrongly attached rays, turning 

 them into proper position, etc. 



This difficulty, due to the uncoordinated turning of b and c. 

 was never fully met. There would appear to be some permanent 

 peculiarity, perhaps of a structural character, which makes it 

 difficult for b and c to twist and pull in a coordinated way. The 

 rays a and b worked together readily, as do also c and d. The 

 difficulty which b and c have in working together results in ob- 

 scuring the effects of training in other respects. The starfish 

 soon came to begin its reaction by attaching b and c first. But 

 these being placed in an uncoordinated way, other rays were sub- 

 sequently attached ; then either b or c or both were released, and 

 the turning took place finally on other rays. In a record of the 

 method of final turning therefore, there would be no indication 

 of the efi'ects of training, though this was clearly present in the 

 first action. 



The training was thus continued for eighteen days, ten lessons 

 being given per day. The purpose was to determine whether 

 habits of some permanence could be formed, — the former experi- 

 ments having shown the possibility of temporary modification 

 through training. 



At the end of these 18 days (180 lessons), the starfish was 

 allowed to remain undisturbed in the aquarium for twenty-four 

 hours, then was given ten trials without any outside interference. 

 The effects of training showed themselves, as did also the effects 

 of the original tendency. The starfish turned three times out 

 of ten on the rays b and c. At the beginning, as will be recalled, 

 it never used this pair, and could not be induced to do so even 

 when no other rays were permitted to attach themselves. The 

 results of the ten trials were : d -{- e, 5 ; b -{- c, 3 ; d -\- c, 2. 



