THE ORGANIZATION OF THE PROTOZOA 59 



fibres, but with chromosomes apparently rudimentary or absent. 

 Such a spindle is stated to persist and to grow greatly in length, 

 one pole of it finally projecting beyond the anterior end of the body. 

 The centrosome at the proximal pole of the spindle becomes the 

 blepharoplast or basal granule of the flagellum ; the centrodesmose 

 itself becomes the flagellum, or at least its axial elastic filament ;. 



N 



FIG. 30. Development of the locomotor apparatus of trypanosomes. A F, De- 

 velopment of Trypanosoma noctuce : A, the single nucleus of the "ookinete " 

 is dividing into two unequal halves ; in each half a centriole is seen, connected 

 with its twin by a centrodesmose ; B, the division of the nucleus complete ; 

 the two sister-nuclei still connected by a centrodesmose uniting the centrioles r 



C, the smaller nucleus (n. ) is dividing unequally to furnish a third nucleus (h.g. ) ; 



D, E, the third nucleus is dividing to furnish a proximal (b.g. 1 ) and a distal 

 (b.g. 2 ) centriole, while the fibrils of the achromatic spindle become the myo- 

 nemes (my. ) ; F, development of the trypanosome N, trophonucleus ; n, kineto- 

 nucleus; b.q. 1 , basal granule (true blepharoplast) of the flagellum. In C the 

 pigment (P) present in the earlier stages is being thrown off. After Schau- 

 dinn (132). 



G, stage in the development of the merozoite of Trypanosoma rotatorium 

 into the trypanosome-form ; A T , trophonucleus, still connected by a cen- 

 trodesmose with n, the kinetonucleus, which has budded off b.g., the basal 

 granule of the flagellum. After Machado (409). 



the distal centrosome is carried out on the tip of the flagellum ; and 

 the mantle fibres form the myonemes, stated in this case to be eight 

 in number, of the body, which are continued on into the contractile 

 sheath of the flagellum (Fig. 30). However fascinating the views 

 put forward by Schaudinn, with regard to these points, may be, it 

 must be stated that the greatest doubt attaches to the correctness 



