460 
Trypanosoma lewisi 
mentioned. In the first period of chronic infection curious forms may 
be seen, with a very elongated hind end (Diagram VI, fig. 2). Prowazek 
mentions them and considers that they have no supporting fibrillae and 
are consequently very metabolic. 
(a) The yroto'plasm. Between the nucleus and the blepharoplast a 
filament may frequently be observed, staining blue with Giemsa. I have 
already referred to this structure in an earlier paper (1910) (Diagram I, 
fig. 1). This filament is probably to be liomologised with similar 
structures found in T. gamhiense and T. brucei (Robertson, 1906). 
IMoore, Breinl and Kindle (1908) do not mention it as occurring in 
T. lewisi, but I have observed it so fi’equently and under so many 
conditions of fixation and staining that a mistake can be excluded. 
Generally the filament is quite continuous, but sometimes it breaks up 
in a row of irregular granules, which are, however, different from the 
chromidia, which stain red with Giemsa (Diagram I, figs. 1, 2). 
Fig. 1. Continuous axial filament. 
Fig. 2. Axial filament broken up. 
The structure of the protoplasm was considered in my previous 
paper. 
(b) The blepharoplast is a rod-shaped organellum, and can only be 
studied in preparations carefully stained with Giemsa. If it is over¬ 
stained the achromatic part cannot be distinguished from the chromatic 
part. In many cases the blepharoplast is composed of two chromatic 
granules, united by a substance staining pink with Giemsa (achromatic 
substance) (Diagram I). The presence of these two granules does not 
indicate a division of the blepharoplast, it is a premature division of the 
centriolic apparatus such as is often met with (Prowazek, 1909). Moore, 
Breinl and Kindle (1908) have described a similar structure, which 
