SPECIAL MORPHOLOGY OF THE PROTOZOAN NUCLEUS 25 I 



('93) in Achromatium. A careful distinction should be made be- 

 tween these types. In Loxophyllum (Balbiani, '6o), Urostyla (Bergh, 

 '89), and Tetramitus (Calkins, '98), the chromatin granules come 

 together and form a single nucleus prior to division. 



B 



^~KL 



E 



Fig. 134. — Types of nuclei. [A. Calcituba polymorpha Roboz, from SCH AUDINN. B. Colptdium 

 colpoda, from a preparation. C. Euglena vlridis Ehr. irom a preparation. D. letramiius ctulomo- 

 nas, n. sp. E. Noctiluca miliaris Sur., from a preparation.] 



A single karyosome (A) becomes vesicular, and ultimately gives rise to several daughter-karyo- 

 somes (so-called "fragmentation" Schaudinn). Several karyosomes in Noctduca (E) hold the 

 chromatin, the rest of the nucleus is filled with "achromatic " granules. In Tetramitus chilomonas 

 (D) the chromatin is scattered throughout the cell; the lighter-colored body in the centre of the 

 cell is the homologue of the deeply stained central body in Euglena (C). 



