ACTINIAN BEHAVIOR 



201 



Metridium but removed them before they were swallowed and 

 then, after the tentacles of that side began to lose in responsive- 

 ness, I tested those of the other side to see if they too had lost 

 in their capacity to respond. The times in seconds required for 

 the swallowing of each piece of food are recorded in the following 

 table. The rejection of a piece of food is indicated by the sign 

 of infinity. 



It must be evident from an inspection of table I that the 

 right side of the animal gave no evidence of having been influ- 

 enced by the left and that therefore we are not warranted in 



TABLE I 



Time in seconds for the transfer by the tentacles of Metridium of small pieces of 

 mussel to the mouth whereupon they were removed as they were about to be swal- 

 lowed. Sixteen trials were made on the left side and then the same number on the 

 right, oo indicates a discharge of the piece of meat at the periphery of the oral 

 disc 



assuming that the experience of one side is transmitted nerv- 

 ously to the other. In other experiments, in which the frag- 

 ments of mussel delivered to the tentacles of the first side were 

 allowed to be swallowed instead of being removed, the tentacles 

 of the opposite side very regularly exhibited a decline in re- 

 sponsiveness. I therefore believe that this change is due to the 

 food introduced into the gastrovascular cavity, and, since the 

 ^* pieces of food were very small, not to the accidental transfer of 

 food juices from the side of the disc stimulated to the other, as 

 suggested by Gee ('13). 



To remove any doubt on this point I adopted a modification 

 of an experiment tried by Gee ('13) and injected by means of a 

 fine glass syringe through the column wall of small specimens 

 of Metridium a considerable amount of mussel juice into their 

 gastrovascular spaces. This operation is easily accomplished 



