234 Proceedings of the Royal Physical Society. 



according to Prowazek, is the early stage of parthenogenesis, 

 but further stages were not met with, and the cross bar 

 arrangement of chromatin has probably, as will be seen later, 

 another explanation. The process very probably occurs, but 

 must be very obscure. From Prowazek's account these ap- 

 pearances are much clearer in Trypanosoma lewisi. Trypano- 

 soma hrucei, by itself, does not give sufficient evidence to 

 enable one to form a definite conclusion as to the nature 

 of this phenomenon. 



The feature of greatest interest in this material is the 

 presence of a well-marked line, which passes from the 

 blepharoplast anteriorly to the tip of the body, taking the 

 flagellum-bearing extremity as the anterior end of the 

 creature (Figs. 5-10). This line is not a chromatic structure, 

 though it may on occasions apparently carry chromatin. It 

 stains a deep violet-blue, with the modification of the 

 Eomanowski method which I used; it stains also deeply 

 with gentian-violet and methyl-green; moreover, safranin, 

 and Heidenhain's iron hsematoxylin, which were in every 

 other respect perfectly useless stains, showed this line in 

 several specimens. The course of the central line is often 

 marked at the posterior end by a rather irregular and 

 indefinite violet-blue granule, more especially where there 

 is a vacuole in front of the blepharoplast ; in these cases the 

 granule and terminal portion of the line lie immediately in 

 front of the vacuole (Figs. 5, 6, 8). Anteriorly, there is 

 another granule which is much smaller and very inconstant ; 

 in favourable specimens a small vacuole may be seen just 

 posterior to the granule (Fig. 8). The central line is present 

 with greater or less distinctness in a very large number of 

 individuals. In many cases it is connected with the karyo- 

 some ; this is particularly clear in individuals where the 

 karyosome is divided into two. A very common condition 

 for trypanosomes in this material is to be seen in Figs. 5, 6. 

 Here there is no sign of division in either blepharoplast or 

 plasma, but the karyosome, which is often very large, is 

 divided into two parts, which lie one at each end of the 

 nucleus. The central line in these cases runs uninterruptedly 

 from the blepharoplast, or vacuole, right through both the 



