FINE STRUCTURE 35 



interrupted where new types of cilia begin. The latter investigator 

 made fine distinctions regarding the gullet tube. Its entrance he 

 called the cytostome which leads into a short passage called the 

 pharynx separated by a ridge from the extensive remaining portion 



orsLpomUx 



stomal Rim. 



narrovj'm^ inembrandUa.r baiui 



frontal Jield 



myoneme. 



C^laslome 



Fig. 6, Structure of the gullet of 5. coernleus. 



A. Exposure of gullet everted by pressure. (After Andrews, 



1946.). 



B. Schematic course of myonemes in the gullet lining, 

 affording possiblity of peristalsis. (After Dierks, 1926a.) 



or esophagus. Each of these parts was.described as having its own 

 special ciliation: the ''cytostomial" cilia look like the pharyngeals 

 but have the special function of selecting the food particles, and 

 the esophageal ciUa were said to be different, the distance between 

 cilia increasing as they are followed down into the gullet. Andrews 

 agrees with Dierks that in the profundity of the gullet the 



