62 



BIOLOGY OF THE PROTOZOA 



latter as yet, at least, having no specific significance, while for the 

 endosomes having functions characteristic of the kinetic complex 

 a specific term may well be applied. In the present work I shall 

 employ the term endosome in a general way to indicate all central 

 intranuclear structures including those of kinetic function, while 

 for those which are known to be of the nature of kinetic elements 

 I shall use the term endohasal body. 



The endosome-bearing vesicular nuclei present manifold variations 

 in the arrangement of chromatin. In some the entire chromatin 

 content is confined to the endosome which seems to rest in the center 



Fig. 25. — Division in Euglcna viridis; nucleus with endohasal body. A, preparing 

 for division, the endohasal hody surrounded hy "chromosomes;" B, C and D, suc- 

 cessive stages in nuclear division. (From Wilson after Keuten.) 



of a colorless enchylema traversed by strands of linin radiating from 

 the endosome to the nuclear membrane (Arcella vvlgaru, Cochlio- 

 podium bilimbosum and rhizopods generally, as well as in many 

 Coccidia and Gregarinida). In other cases the endosome retains 

 only a little of the chromatin, the bulk of which is present as a 

 dense network in the zone between endosome and membrane 

 (Amceba infestinalis, A. cri/sfaUigera, etc.). In still other cases the 

 chromomeres are distributed more or less uniformly throughout the 

 nuclear reticulum {Eugh/pha alveolafd, etc.). 



In vesicular nuclei with endohasal bodies the chromatin may be 



