G. H. F. Nuttall 
209 
appear in the protoplasm especially toward the flagellar end. The 
number and size of these granules increase rapidly, after which they 
disappear with the progressive dissolution of the parasite. After a time 
only nuclear detritus, portions of the ectoplasm and the flagellar 
filaments remain, and finally all traces of the parasites disappear. The 
red- or purple-staining rounded granules doubtless owe their origin to 
the breaking up of the nuclear chromatin, but the large number of 
granules observed in some cases suggests that they may also have some 
other origin. Similar changes occur in trypanosomes in dying animals 
which have been left untreated. Future investigations will no doubt 
determine more regarding the origin and nature of these granules which 
react to chromatin stains 1 . 
In conclusion, I desire especially to thank Geheimrath Ehrlich for 
placing a supply of arsenophenylglycin 2 at my disposal. 
REFERENCES. 
Swellengrebel, N. H. (1909). Zur Kenntnis des Baues und der Zellteilung von 
Trypanosoma gambiense und Tr. equinum. Tijdschr. d. Ned. Dierk. Vereen (2), 
Dl. xi. Afl. pp. 80—98, pi. v. (reprint). 
Woodcock, H. M. (iv. 1906). The Haemoflagellates: A review of present know¬ 
ledge relating to the trypanosomes and allied forms. Part I. Quart. Journ. 
Microsc. Sci. Yol. l. pp. 151—231. 22 text-figures (reprint). 
1 With regard to these granules we may note the following: Woodcock (1906, p. 228, 
Fig. 21) gives a brief description of the involution forms in which chromatolysis vacuolisa- 
tion and change of form occur. In chromatolysis, according to Woodcock, the chromatic 
constituents of the nucleus pass out into the protoplasm or else direct fragmentation of 
the nucleus occurs. 
Swellengrebel (1909, p. 87 et seq.) evidently refers to similar extranuclear granules 
occurring in T. gambiense and which he observed in the later stages of infection. He 
does not regard them as consisting of chromatin but of a substance allied to volutin. 
They stain red by Giemsa and are scarce in the early period of infection. Some of his 
figures much resemble what I have seen. 
2 See in this connection Boehl, W. (11. m. 1909). Heilversuche mit Arsenophenyl¬ 
glycin bei Trypanosomiasis, Zeitsclir. f. Immunitatsforsch. u. exper. Therapie, i. 
pp. 633—649. 
