THE HA E MO FLA GEL LA TES 



parasites now become gregariniform, and strongly recall the similar 

 phase described by Le"ger (48, 51) in certain Herpetomonads. The 

 Trypanosome bores into an epithelial cell of the stomach by means 

 of its flagellum, which is reduced to a short, rod- like organella. 

 Binary fission may go on, often leading to the formation of a dense 

 layer of attached parasites. On the parasites again becoming try- 

 paniform, the flagellar apparatus is reconstituted by the kineto- 

 nucleus. This alternation of resting and active periods is limited. 

 Eventually the indifferent Trypanosomes may pass into the blood 



-m.k. 



E. 



F. 



FIG. 23. 



Development of microgametocyte and male Trypanosomes from an ookinete of male character, 

 (After Schaudinn.) m.n, male nuclei; f.n, degenerating female nucleus; m.t, male tropho- 

 nucleus ; m.k, male kinetomicleus ; M.T, male Trypanosome ; r.b, residual body. 



of the owl ; or they may apparently become sexual forms, male 

 or female ; or else, during a period of hunger, they die off. 



In the development of an ookinete of male character, or micro- 

 gametocyte, there is an early separation of the nuclear constituents 

 into two halves, male and female. The female portion consists of 

 a large, loose nucleus (Fig. 23, C and D, f.n), which gradually 

 degenerates and disappears. The male portion, on the other hand, 

 gives rise to eight little double-nuclei (c and D, m.n), each consisting 

 of trophic and kinetic portions. The microgametocyte now becomes 

 rounded, the eight double-nuclei take up a peripheral position (E), and 

 the cytoplasm opposite each grows out as a little prominence. As- 



