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pale-pink, and it is devoid of chromatin. It causes a slight projection 
of the periplast into the cytopharynx. 
The blepharoplast is a small oval body constantly situated in the 
periplast at the posterior end of the cytopharynx, and when any traces 
of a flagellar apparatus are present in the cytopharynx, they are seen 
to run up towards it. In structure, the blepharoplast consists of a 
homogeneous-looking matrix, which stains rosy-red, and is devoid of 
chromatin. It can be distinguished from the chromidia, by which it is 
often surrounded, only by its staining reaction, the chromidia appearing 
deep carmine. 
The chromidia consist of a group of deeply-staining carmine-coloured 
granules, each of which is often as large as the blepharoplast. The 
group has a characteristic position at the extreme posterior end of the 
cell, but very often an isolated granule occurs close to the blepharoplast, 
the significance of which is not obvious. The chromidia are often 
obscured from view when the periplast is densely stained. (PI. VIII, 
figs. 23-25.) 
(2) The oval forms are connected with the cysts by intermediate 
forms which are about the same length as the cysts, but broader. The 
typical oval forms are longer and possess a pointed anterior extremity, 
corresponding in position to the cytostome of the cyst. In stained 
specimens the protoplasm is seen now to be undifferentiated into the 
periplast and cytopharynx. The chromidia are scattered throughout 
the cell, and the nucleus and blepharoplast are partly chromatinised. 
It is consequently very difficult to distinguish the blepharoplast from one 
of the chromidia, but it lies to the side, or in front, of the centrally 
placed nucleus. (PI. VIII, figs. 1-2.) 
(3) The oval forms with a fagellum differ from the preceding forms 
only in possessing a free flagellum, the length of which equals that of 
the body of the cell, and in the nucleus and blepharoplast being more 
chromatinised. 
The flagellar apparatus consists of (i) a rigid rod-shaped and heavily 
chromatinised body, the rhizoplast, lying between the blepharoplast and 
the anterior end of the cell, but having no chromatin connection with the 
blepharoplast; and (ii) the young flagellum, which consists of a delicate 
prolongation of the cell-protoplasm, staining pale-pink, investing a 
filament of chromatin, staining deep carmine, which runs into the 
anterior end of the rhizoplast (PI. IX, fig. 6). In those cells possessing 
a divided rhizoplast, two chromatin filaments may be present in the 
protoplasmic prolongation of the cell, each arising from one of the 
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