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THE AMEBIC AN NATURALIST [Vol. LII 



the flagellum should be one of rotation, although theory 

 would imply a partial rotation in the primitive flagellate 

 forms. The method of movement by means of the flagel- 

 lum furnishes a problem of considerable difficulty which 

 N 



has received attention from several investigators, notably 

 Delage and Herouard (1896), Goodspeed and Moore 

 (1911), Biitschli and others. 

 There are several inferences of an axiomatic nature 



