398 



GARY N. CALKINS AND RACHEL C. BOWLING. 



\vithout division of the cell and such sporoblasts with four nuclei 

 are much more common than are the binucleated ones (Fig. 16). 



FIG. 16. Group of developing sporoblasts, 2 with 2 nuclei, 2 with 4 nuclei and 

 one with 8 nuclei no cytoplasmic division. Section. Camera lucida. X i7S- 



A third division gives rise to the eight nuclei of the sporozoites 

 and at this stage the cytoplasm divides into eight elongated cells 

 each bearing a nucleus; each is a sporozoite (Figs. 16 and 17). 



FIG. 17. Group of late sporoblasts from one sporocyst, each with 8 sporozoites 

 In one the sporoblast suture is clearly indicated. Section. Camera lucida. 

 X 1750. 



During this later period the sporoblast capsule becomes 

 definitely formed and rigid ; near each pole a distinct ring of more 



