IBS STUDIES IN GENERAL PHYSIOLOGY 



and a piece of meat to the other, and then threw the whole 

 upon the outstretched tentacles of a hungry animal. The 

 tentacles which came in contact with the meat reacted at once 

 by bending by which the meat was carried to the mouth ; the 

 tentacles in contact with the paper did not react. I removed 

 the thread and reversed the position of the meat and paper 

 upon the oral plate, so that the tentacles which had before 

 been touched by the paper were now in contact with the 

 meat. The tentacles touched by the meat carried it to the 

 mouth, while the tentacles touched by the paper let it fall. 

 The meat was thru crowded into the mouth, and the thread 

 was pulled in after it; but the paper and a piece of the 

 thread remained outside of the oral opening. No change 

 occurred within the next twenty-four hours. After this 

 period the thread was ejected, but without the meat. The 

 latter had probably been digested. I have often repeated 

 this experiment with the same result; only occasionally the 

 thread was ejected earlier, and then a piece or all of the 

 undigested meat was still attached to the thread. 



I divided an A. equina into two pieces by a transverse 

 incision. The oral piece which I shall call the head piece 

 -had the old normal mouth at its oral end; the body-cavity 

 was open also at the aboral end of the head piece, and food 

 was taken up here likewise, even though no tentacles were 

 present. The old oral mouth of the head piece showed the 

 same choice in the taking up of food after the division of the 

 animal as before. But the aboral mouth of the head piece 

 at times took up paper wads and swallowed them. Yet I 

 saw it refuse paper wads while at the same time it eagerly 

 took up pieces of crab meat. 



While the old mouth at times refused meat, the aboral 

 mouth was nearly always ready to take up food. 



3. The following means, however, served to decrease the 

 irritability of the mouth toward chemical and mechanical 



