INTESTINAL TRYPANOPLASMAS OF FISHES. 
179 
shape, which persists to quite a late stage in division. The 
karyosome appears to act as an internal division centre, and 
no trace of individual chromosomes can be seen at any stage 
of division. 
Text-figure 1. 
Bl. Blepharoplast. F. Free flagellum. Ki. Kinetonucleus. M. F. 
Membrane flagellum. Tr. Trophonucleus. Tr. sp. Troplionucleus 
spindle. 
Fig. 1. — Early stage of division of Tr jpanoplasma congri. The 
whole body of the animal is shorter and stouter. The basal granule has 
divided, the anterior flagellum is split along about a quarter of its 
length, and the beginning of the splitting of the posterior flagellum is 
shown. The kinetonucleus is slightly thicker, and the trophonucleus 
is distinctly enlarged. The intra-nuclear chromatin granules have 
probably condensed upon the karyosome, which no longer presents the 
hard outline characteristic of the resting nucleus. 
Fig. 2. — The flagella have now split along their whole length. The 
karyosome has become drawn out into the characteristic dumb-bell 
shape within the nuclear membrane. 
Fig. 3. — The body of the animal has become still shorter. The 
kinetonucleus is becoming enlarged and losing its intense capacity for 
nuclear stain. The dividing trophonucleus is almost parallel to the 
longitudinal axis of the animal’s body. 
Fig. 4. — The body of the animal has become still more deformed. 
The basal granules with their flagella have shifted apart. The kineto- 
nucleus has become thickened, and has now lost its intense capacity for 
nuclear stains, its lower border is crossed by the trophonuclear dumb-bell. 
Fig. 5. — The basal granules with their flagella now lie at opposite 
sides of the dividing animal. The lower limb of the enlarged kineto- 
nucleus has adopted its characteristic position at right angles to the 
trophonuclear dumb-bell. 
Fig. 6. — A slightly later stage than the previous figure, showing the 
characteristic relations of the enlarged kinetonucleus and the tropho- 
nuclear dumb-bell. 
Fig. 7. — A late stage of division. The two products of division are 
still united by a broad band of cytoplasm, through which the kineto- 
nucleus and trophonuclei still retain their connection. 
Fig. 8. — A recently divided form showing the characteristic rounded 
shape, the elongate kinetonucleus, and the unabsorbed strand which had 
connected the trophonuclei. The full length of the flagella are not shown.. 
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