PLATE 33 

 All figures of cross-sections through the same organism. 2.5/i thick. X 670. 



Fig. 7. Oral groove at the beginning of the eytostome and cytopharynx, 

 showing ends of peripheral fibers connected with the basal granules and 

 trichoeysts. 



Fig. 8. Through the mid-eytostome region, showing membranelle brush of 

 anterior membranelle zone. 



Fig. 9. Through the posterior eytostome region and the cytopharynx, show- 

 ing membranelle brush of anterior membranelle zone. 



Fig. 10. Through cytopharynx, showing membranelle brush of anterior 

 zone and beginning of posterior membranelle zone. 



Fig. 11. Through indented portion of cytopharynx and posterior mem- 

 branelle zone. 



Fig. 12. Through extreme posterior end of cytopharynx, showing cilia of 

 posterior membranelle zone partly obscured by ingested food bodies. 



[358] 



