326 
III. —( a ) The “ Mega ” forms may have long anterior and posterior 
(Plate XXVII, fig. 39) ends, a contracted posterior extremity 
(Plate XXVII, figs. 35 and 36), or a short contracted body (Plate 
XXVII, fig. 37). In fresh preparations the striations are well seen in 
the long forms;* these may coil up exactly as does T. karyozcuklon 
(Plate XXVIII, fig. 43) (see below). T. mega has been seen to 
gradually become more rounded until it became spherical. It then 
lost its flagellum. The forms with contracted posterior extremity and 
contracted body (Plate XXVII, figs. 35-37) probably represent stages 
in this process. From them development was not observed. 
In the type of T. mega with a short contracted body the length is 
40 n, the width at the posterior part 20 n, the nucleus 3'3/t, and the 
blepharoplast l’l/i posterior to it. The width of the nucleus varies 
greatly; in most cases it extends completely across the body, while 
in others it was at one side and only 2'2/i wide. 
T. mega (type) measures as follows — 
Measurement I 
.. 4'0/z 
„ II 
... 1-3 to 
6‘o/i 
„ III ... 
... ri to 
4 ‘ 4 / i 
„ IV ... 
... 15-0 to 
53 ‘o^ 
„ V ... 
... 8-2 to 
ifrQfl 
„ VI ... 
... 3’3 to 
iro/t 
Total length of parasite 
... 52-0 to 
io4 - o/i 
Width of nucleus 
2*2 to 
The original description of Trypanosoma mega holds good for 
these parasites. In a few parasites there was a slight variation in 
the structure of the nucleus. The clear area just anterior to the 
nucleus was still present, but the nuclear area of irregular chromatin 
was replaced by an arrangement of about eight or nine processes 
which radiated from a focus placed at the middle of the anterior wall 
of the nucleus. 1 hey seemed to be placed in a deep purple stroma, 
and some of them contained a few reddish granules. A somewhat 
similar appearance is illustrated by Broden. 7 
(b) 1 here was another form similar to the “ Mega ” type except for 
the very coarse reticular structure of the cytoplasm (Plate XXVII, 
* It may be stated here that more or less distinct longitudinal striations were 
present in every type of trypanosome mentioned in this paper. 
