328 WOOLFORD B. BAKER. 



flagellum. The smaller branch passes from its anchoring granule 

 through the reservoir to a point opposite or above the lens-shaped 

 enlargement on the larger and there fuses with it. In the early 

 stages of development after division the two branches appear to 

 be entirely separate, though the larger grows more rapidly and 

 extends from the cytostome before fusion with the smaller. In 

 some few cases observed there is an indication that the two 

 branches may remain separate not only at the outset but perma- 

 nently. The granule at the base of the larger branch seems to 

 originate first from the kinetic center and is therefore interpreted 

 as the blepharoplast. This divides and gives rise to the granule 

 at the base of the smaller branch which granule is here designated 

 the basal granule. 



During the late prophase and continuing for some time after 

 division is completed there may be seen a rhizoplast extending 

 from the blepharoplast into the cytoplasm and ending on the 

 nuclear membrane in a heavily staining body which originates in 

 the early prophase from the endosome. In older animals such a 

 connection cannot be detected, indicating that direct connection 

 with the nucleus is not necessary for the proper functioning of the 

 motor apparatus. The early connection of the various parts 

 seems sufficient grounds however, to designate the motor appa- 

 ratus of Euglena agilis as a neuro-motor system as defined by 

 Kofoid and his students. Their definition involves an integrated 

 motor system connecting with the nucleus. (Kofoid and 

 Christiansen, 19150, b; Kofoid, 1916; Swezy, 1916; Boeck, 1917; 

 Kofoid and Swezy, 19190, b, 1920, 1922; Hall, 1923.) It is true 

 that only during the later division stages and for a short time 

 after binary fission there is a complete integration of nucleus and 

 motor apparatus, even to the presence of an intra-nuclear 

 rhizoplast (Fig. 13). The presence of these rhizoplasts is merely 

 reminiscent of the process of development of the parts of the 

 motor apparatus, as will be described later, since they are not 

 permanent structures of the cell. 



REPRODUCTION. 



The typical method of reproduction as described for Euglenidae 

 is by longitudinal fission, accompanied by division of the nucleus 



