DERIVED ORGANIZATION 



97 



matin is similarly divided and distributed but the endosome appar- 

 ently contains some chromatin in addition for a complete division 

 figure is formed from its substances, chromatin-like granules form- 

 ing a nuclear plate (Fig. 52). In other cases, as for example End- 

 amoeba intestinalis and E. cobayae, the peripheral chromatin is 

 broken up into chromomeres, which collect in the center of a spindle 



ife: 



'■•.n't. 





Fig. 52. — Amoeba vespertilio Dof. Origin of the spindle within the nucleus (1, 2), 

 nuclear division (5, 6, 7), and reconstruction of nuclei after division (3, 4, 8, 9). 

 (After Doflein.) 



from the linin of the nucleus and with centrioles at the poles. In 

 Chlamydophrys the endosome apparently divides before it disap- 

 pears, the chromosomes being formed from the peripheral chromatin. 

 In still another general type, derived also from vesicular nuclei, 

 the chromatin in the form of chromomeres is suspended in a loose 

 reticulum. In Opalina chromatin appears to be aggregated in a 

 few larger granules, which divide where they happen to be without 

 7 



