700 H. .M. WOUDCOC'K. 



typical daughter-parasites often remain entangled by their 

 fiagella after division. Now, as I have stated, the flagellar ends 

 of the two individuals resulting from division (i.e. longitudinal 

 fission) always become widely separated, and I have never 

 seen any instance of such an occurrence. Even in the rare 

 cases where nmltiple (quadruple) longitudinal fission is pro- 

 ceeding, the flagella are all distinctly free from one another, 

 and when the cytoplasmic division was completed, the 

 daughter-individuals would doubtless separate. Moreover, 

 from Novy and McNeal's figures, it is obvious that the divid- 

 ing forms in their cultures behaved in a similar way (cf. figs. 

 1,2, and 5, PI. 7). 



Hence, to conclude, I i-egard Xovy and McNeal's rosettes, 

 in wliich the parasites are attached by their flagella, equally 

 with those in my own cultures, as true agglomeration clus- 

 ters, originating, and in the main increasing, by the coming 

 together of independent individuals. 'J'here can be no doubt, 

 it may be pointed out, that agglomeration of trypanosomes 

 by the flagellar end does occur in the invertebrate host; the 

 process has been described, for instance, in the case of T. 

 lewisi,when in a louse, by Prowazek (22), and when in a 

 flea, by Swingle (33). 



On the other hand, there is nu reason to doubt that in 

 certain types or phases of the parasite agglomeration in cultures 

 may take place by the aflagellar end ; this is stated by Novy 

 and McNeal to occur in the case of their " spirochetes.'' I 

 have never had cultures which showed a suflficient number of 

 parasites belonging to this type for agglomeration to occur, 

 and so am unable to say more upon this point. It is interest- 

 ing to note, however, that agglomeration of trypanosomes 

 in the blood of the vertebrate hosts takes place by the 

 aflagellar (kiuetouuclear) end, and these " spirochtetes " are 

 also definitely trypaniform; in coutra-distinction to these, para- 

 sites of the trypanomonad type form rosettes which have 

 their flaoellar ends attached. 



