MITOSIS AND MULTIPLE FISSION IN TRICHOMONAD 

 FLAGELLATES. 



By Chables Atwood Ivofoid and Olive Swezt. 



Received, June 2, 1915. 

 Table of Contents. 



Page. 



Material 290 



Technique 290 



Trichomonas augusta Alexeieff 293 



The vegetative or premitotic stage 293 



Binary fission in Trichomonas augusta 314 



Metaphase and amphiaster 321 



Amphiaster stage 321 



The anaphase 324 



The telophase 324 



Behavior during plasmotomy 329 



Plane of division 331 



Method of division 332 



Multiple fission in Trichomonas augusta 334 



Trichomonas niuris Hartmann 337 



The trophozoite 337 



Binary fission in Trichomonas muris 338 



Multiple mitosis in Trichomonas muris 340 



Tetratrichomonas prowazeki Alexeieff 340 



The trophozoite 341 



Binary fission in Tetratrichomonas prowazeki 343 



Multiple fission in Tetratrichomonas prowazeki 343 



Eutrichomastix serpentis (Dobell) 344 



Material 344 



Historical 344 



The trophozoite 346 



Binary fission in Eutrichomastix serpentis 349 



Multiple mitosis in Eutrichomastix serpentis 351 



Discussion of multiple mitosis 352 



Addendum 354 



Conclusions 357 



Literature cited 360 



Explanation of plates 364 



The observations and conclusions here recorded deal with the 

 processes of binary and multiple fission and the accompanying phe- 

 nomena of mitosis in trichomonad flagellates, protozoans parasitic in 

 the digestive tract of vertebrates. The analysis is of general interest 

 because of the light it throws on the evolution of the nuclear and 

 extranuclear organs of the cell, especially on the kinetonucleus and 



