144 D. H. WENRICH 



I have not been able to find stages showing any division of 

 the parabasal body. In all the anaphases and later stages 

 (figs. 26 and 28) there appears to be a parabasal for each blepharo- 

 plast. Whether the old one disappears and two new ones grow 

 out, or whether the old one remains and one new one grows 

 out, or whether some other mode of origin may prevail has not 

 been determined. One point should be noted, however, namely, 

 that in these anaphases and telophases the parabasal attached 

 to the daughter blepharoplast is always smaller than the one 

 connected with the old blepharoplast. Considering a possible 

 analogy with the chromatic basal rod, this fact might be inter- 

 preted as indicating that the old parabasal persists and a new 

 one grows out from the new blepharoplast. The one attached 

 to the old blepharoplast is not so long as the longest ones seen 

 in the non-dividing and earlier prophase stages (figs. 3, 4, 5, 16), 

 but is comparable in length to the portion proximal to the con- 

 striction as seen in figures 4 and 5 or proximal to the fainter 

 area in figure 16. The suggestion already made that the portion 

 distal to the constriction may become detached will be recalled. 



The origin of all the new structures has been discussed, except 

 the cytostome. This structure is not much in evidence during 

 the metaphases and anaphase, but two cytostomes appear in 

 the telophase. It is possible that the old one, like the axostyle, 

 disappears, and two new ones are formed. Before division of the 

 cell body, all the organelles in the two sets apparently become 

 developed to a condition corresponding to that of the original 

 set. 



No cases have been found showing the constriction of the cell 

 body in my fixed and stained slides, but I have frequently 

 observed this process in the living animals. It takes place 

 rapidly and the two separating individuals always appear to be 

 of equal size and completely developed. The long interval 

 between the division of the nucleus and the division of the cell 

 body doubtless serves to allow the new organelles to attain com- 

 plete development before the daughter cells separate. 



I think it is worth while to point out that according to the 

 evidence which I have presented there appear to be only two 



