STRUCTURE AND DIVISION OF TRICHOMONAS 143 



axostyle. It is possible that the chromatic granules seen in the 

 adult along the axostyle from the blepharoplast to behind the 

 nucleus (figs. 3, 7, and 8) are the same as the ones which appear 

 to be concerned in the formation of the new axostyles. 



It is probable that the degeneration of the axostyle in the 

 late prophases accounts for the rounding up of these animals 

 at about that stage in the division process. 



Kuczynski ('14, '18) saw and figured the degeneration of the 

 old axostyle and the growing out of the new ones from the 

 blepharoplasts, and Martin and Robertson ('11) report the same 

 thing for T. eberthi. Wenyon states that the axostyle ('pointed 

 organ') divides by longitudinal division, but offers no evidence 

 in support of this statement. Kofoid and Swezy ('15) show one 

 figure (fig. 60) which they interpret as showing division of the 

 axostyle in T. muris. But the figure is also open to the interpre- 

 tation as a partial superposition of two independently formed 

 elements, and since it is the only one they could find after pro- 

 longed search, the evidence is not very conclusive. Since the 

 evidence of the degeneration of the old axostyle and the origin 

 of new ones as outgrowths from the blepharoplasts is so con- 

 clusive in my material and in the results reported by Kuczynski, 

 the origin of this structure by splitting may be regarded as 

 extremely doubtful, at least for T. muris. Dobell ('09) and 

 others were undoubtedly in error in believing that the new 

 axostyles developed from the paradesmose. This structure 

 retains its connection with the two blepharoplasts for some 

 time after the division of the nucleus (figs. 31, 34), but eventually 

 disappears. 



Kofoid and Swezy state for T. muris that the long row ol 

 granules disappears during metaphase and reappears in the 

 telophase. I have been able to find them at practically all 

 stages of division but, as previously noted (p. 128), there is 

 evidence that the old row may be replaced by a new one which 

 is budded off from the ventral (inner) side of the chromatic 

 basal rod. Just how the new chromatic basal comes to have an 

 associated row of granules has not been determined. 



