64 SUMMARY OF CURRENT RESEARCHES RELATING TO 



throughout the period of division, with nuclear separation by constric- 

 tion, which simulates amitosis. It is, however, essentially mitotic, with 

 extranuclear division centres, intranuclear spindle fibres, and chromosome 

 organization out of a chromatin network and skein. The chromo- 

 somes are four in Tetratrichomonas proivazehi, five in Trichomonas augusta, 

 T. muris, and Eutrichomastix serpentis. There is one small one and 

 some fairly constant-size differences among the larger ones. They 

 appear to be split longitudinally prior to their arrangement in the equa- 



chr. b<u. r- 



mar. fU. -J 



post. ax. gr ..,..: 

 post fL 



t Diagram of Trichomonas augusta. 



Ant.fl., anterior flagella; ax., axostyle ; ax.chr., axostylar chromidia; 

 bl.y blepharoplast ; chr. bas. r., chromatic basal rod or parabasal body ; 

 cyt., cytostome ; cyt. chr., cytoplasmic chromidia ; mar. fit, marginal 

 fQament; w., nucleus ; post.ax.gr., posterior axostylar granules; 

 post.fi., posterior flagellum ; rh., rhizoplast connecting blepharoplast 

 and nucleus ; und. m., undulating membrane ; vac, food vacuole. 



torial plate, and seem to slip into an end-to-end position in this plate, or 

 to be parted by a transverse constriction. 



The extranuclear organellas all share in the mitosis. The blepharo- 

 plast — from which flagella, rhizoplast, chromatic margin and basal rod, 

 and axostyle, all take their origin — contains the division centre. It 

 parts into two bodies which go to the two poles of the fusiform 

 mitotic nucleus, spinning out the deeply staining, always extranuclear, 

 paradesmose between them. The daughter blepharoplasts may each 

 divide in the polar position into an axial centrosome and an adjacent 

 basal granule to which flagella, paradesmose, and parabasal are attached. 



