456 0. CLIFFORD D(DBELL. 



A very remarkable fact was sometimes observed in the 

 involution forms. An individual, instead of dividing when 

 it reached a certain size, continued to grow. In this way 

 giant individuals arose, which reached the enormous length 

 of 30 /u, i.e. about twice the normal length. Very few of 

 these were observed, but quite a number reached a length of 

 20 fx — 24 ju. In these exceptionally large forms I was able, 

 in an unexpected manner, to confirm my previous observa- 

 tions on the inter-relationships of nucleus, flagella, and axial 

 rod. Structures which had been made out with great difficulty, 

 and after many hours' watching, were here seen very plainly 

 after an examination lasting a few moments. These giant 

 forms divided abnormally, commonly giving rise to three or 

 four daughter-cells [see fig. 14, PI. 27]. Division rarely 

 became complete, the whole usually fusing into a large 

 amoeboid mass, which finally died. Unfortunately, owing to 

 insufficiency of material, I was never able to obtain stained 

 preparations of these stages. It could be seen in the living 

 animals, however, that each of the daughter individuals 

 possessed a nucleus, axial rod, and full complement of 

 flagella. Sometimes the old axial rod was seen sticking 

 out of the central mass of protoplasm [fig. 14]. 



A very similar atypical division has been described b}'- 

 Prowazek in the allied form. Trichomonas lacert^. Prow. 

 — apparently as a normal occurrence. I cannot think, 

 however, that this is a normal process in Trichomastix 

 s e r p e n t i s . 



Before concluding I may call attention to the resemblance 

 between the basal granule of the flagellar apparatus and the 

 blepharoplast of a trypanosome. As I find that a detailed 

 comparison of these structures has been made already by 

 Laveran and Mesnil in the case of the closely allied form 

 Trichomonas, I refer the reader who may be interested in 

 such speculations to their original paper. 



