Plate II 



Photographs showing different stages in the process of encystment for division. Figs. I, 2, 3 were 

 taken with the same magnification. Fig. 4 was taken with a higher magnification. 



Fig. I A section through an individual encysted for division. The macro-nucleus has elongated 

 and has become constricted. The first division plane is shown appearing at right angles to the long axis 

 of the nucleus. Food vacuoles in different stages of digestion are shown. X 450. 



Fig. 2 A section showing the beginning of the second division plane. X 450. 



Fig. 3 Section through an encysted form which has divided twice to form four individuals. Portions 

 of the four individuals are seen. The nucleus shows in but two. X%50. 



Fig. 4 Section through an encysted form which has divided twice. Three of the four individuals 

 show. The beginnings of the ciliated mouth regions and the nuclei are visible. X 530. 



