246 



THE PATHOGENIC FLAGELLATES 



free flagellum at the posterior end (Fig. 98). Such forms may be 

 readily conceived as coming from bodo-like types in which the pos- 

 terior or trailer flagellum becomes attached to the cell, while the 

 trypanosome type may arise from such forms by the suppression of the 



Fig. 98 



Trypanoplasma borreli. (After Keysselitz.) ^, B, old, developmental stages; C, a so-called 

 "male" form; D,E, so-called "female" forms; G, H, the "copula." 



