334 



FAMILY: TRYPANOSOMIDiE 



may result. As regards the origin of the new flagelliim, there has been 

 some difference of opinion. Some observers, as, for instance, Laveran and 

 Mesnil (1904, 1912), Minchin (1908), Woodcock (1909), and others, have 

 described longitudinal splitting of the flagellum, but the writer (1913a), 

 from observations on Herpetofnonas tnuscarum and trypanosomes, came 

 to the conclusion that a longitudinal division never occurs, and that the 

 new flagellum is the result of the growth of a new axoneme from the newly- 

 formed blepharoplast, a view previously upheld by Schaudinn (1904), 

 MacNeal (1904), and Prowazek (1905). Hartmann and Noller (1918), in 

 a study of the cytology of Tryfanosoma theileri, arrive at the same con- 



FiG. 159. — Dividing Forms of Herpetomonas muscarum (x 2,000). (After 

 Wenton, 1913.) 



The outgrowth of a new axoneme from the divided blephaioplast produces the appearance of an 

 organism with two flagella. 



elusion, as also did Rosenbusch (1909a), though he gave an erroneous 

 description of the division of the kinetoplast. Mackinnon (1910), in the 

 case of H. homolomyicB and H. scatophagce, describes the intracytoplasmic 

 portion of the axoneme as dividing, the new flagellum being then formed 

 as an outgrowth of the new axoneme. There seems little doubt that the 

 flagellum is entirely formed as a result of the outgrowth of a new axoneme 

 from the new blepharoplast, a process which may even commence before 

 division of the blepharoplast is complete. In some cases the new flagel- 

 lum attains a considerable length before the kinetoplast is actually 

 divided, so that the organisms appear to have two flagella. //. muscarum 



