EXPLANATION OF PLATES 



All figures are of Paramaecium, drawn with camera lueida and, unless other- 

 wise stated, stained with Heidenhain's iron haematoxylin. 



Fig. 1. Oral view showing the oral groove, cytostome, and oral whorl of 

 peripheral fibers ramifying out from the neuromotor center. X 356. 



Fig. 2. View of left side, showing meeting points of the anastamosing 

 ends of th.e fibers of the oral whorl with those of the aboral whorl. X 356. 



Fig. 3. Aboral view showing the aboral whorl. X 356. 



Fig. 4. View of left side. The anastamosing ends of the fibers of the oral 

 whorl meet the converging apex of the aboral whorl. X 356. 



Fig. 5. Slightly oblique section, o/j, thick, through the cytostome, showing 

 converging fibers of the oral whorl in the outer endoplasm. X 670. 



Fig. 6. Oblique section through the cytopharynx, showing some of the 

 fibers of the oral whorl and also of the aboral whorl. X 670. 



[356] 



