MORPHOLOGY IX TRICHOMONAS TERMOPSIDIS. 



73 



NUCLEUS. 



The nucleus is an ellipsoidal mass enveloped by a membrane 

 which is sometimes closely applied to the darkly staining nucleo- 

 plasm, but is more frequently found surrounding it a short 



Und. mem 



Ant f/g 

 .Chr. has. 

 Cerrtfobl 



Jt/iizo. 



/Vac. mem. 



_/7*o. chrom 



r 





Chrom. fil. 



chrom. 



Pxo. 



_toc. 



riarcj. fil. 



Post. fla<j. 



> N^ LjJ ^' ^ ^^^F 



FIG. 2. Diagrammatic representation of Trichomonas termopsidis. 



Abbreviations: Und. mem., undulating membrane; Ant. flag., anterior flagella; 

 Chr. has. r., chromatic basal rod; Centrob., centroblepharoplast; Rhizo., rhizoplast; 

 Nuc. mem., nuclear membrane; Cytos., cytostome; Axo. chrom., axostylar chro- 

 midia; Par. b., parabasal body; Chrom. fil., chromatic filament; Cytop. chrom., 

 cytoplasmic chromidia; Axo., axostyle; Vac., vacuole; Marg. fil., marginal 

 filament; Post, flag., posterior flagellum. X 3000. 



distance away, leaving a clear, unstaining zone between the 

 membrane and the nucleus (Fig. 4, B and C). Sometimes this 

 zone is not regularly parallel to the contour of the nucleus, but in 

 all such cases observed, the irregularity seems to be due to de- 

 pressions or elevations in the outline of the nuclear mass, rather 

 than to a collapse of the membrane (Fig. 4, A and D). The 

 length of the resting nucleus is ordinarily about twice its width. 

 It is always situated anterior to the middle of the body, except in 

 dividing forms, where proportions are upset both in the body of 



