86 



Asa Arthur Schaefjer 



around on the aboral side of the disk, in "push ball" fashion, in a 

 rather large circle in the direction from right to left along the 

 dorsal edge. (See Fig. 2.) Since the particles are not got rid of 

 as soon as they strike the disk they accumulate in large, loose 



Fig. 2. Illustrating the "push bair' method of gettuig rid of objectionable particles. The arrows 

 show the direction of beat of the discal cilia, c, mass of carmine grains; /. funnel: in, membranellac; 

 mo., mouth; p, pouch. 



masses which are, after some time, either by a special reaction or 

 by accident — I didn't determine which — dropped over the edge 

 of the disk, opposite the pouch. The carmine masses move slowly 

 and it can be readily seen that the motion is altogether due to the 

 action of the discal cilia. This method of preventing the ingestion 



