1916] 



Sivezy: KinetonHclcus of FlageUaft 



219 



basal body in Crithidia and the trypanosomes ; and (3) its division is 

 by a simple constriction, as is the case also of the parabasal body of 

 the haenioflagellates. 



The next step in tlie evolutionary series has resulted in the produc- 

 tion of two forms on divergent lines, which show striking similarities 



Figs. 34-36. Trypanoplasma congri, after Martin (1913, pi. 9, figs. 3, 7; 

 1910, pi. 21, fig. 1). Fig. 34. Normal active trophozoite. Fig. 3.5. Tropho- 

 zoite showing elongated parabasal body. Fig. 36. Individual showing round- 

 ing-up stage. 



Figs. 37-42. T. dendrocoeli Fantham and Porter, after Gelei (1913, pi. 7, 

 figs. 9, 14, 23). Fig. 37. Individual in the beginning of division: note elong- 

 ated parabasal body. Fig. 38. Later stage of division. Fig. 39. Dividing 

 form with greatly elongated parabasal boilj'. Fig. 40. T. cyiiriiii Plehn, 

 after Martin (1913, pi. 10, fig. 26). Late stage of division, with two daughter 

 nuclei still connected and the parabasal body undivided. Fig. 41. T. congri, 

 after Martin (1910, pi. 21, fig. 8). Late stage of division. Fig. 42. T. iittesti- 

 nalis Leger, after Martin (1913, pi. 9, fig. 20). Late stage of division; or- 

 ganelles completely divided. 



