142 
Piroplasma: Multiplication-forms 
In the absence of observations on the living parasite we consider 
that these points may be taken as characteristic of the genus 
Piroplasma. 
In spite of the fact that dividing forms have not yet been found and 
that the secondary mass of chromatin has not yet been observed P. muris 
may perhaps be included in this genus. 
Piroplasma quadrigemium, an intracorpuscular parasite recently 
observed by Nicolle (xi. 1907) in a small North African rodent ( Cteno- 
dactylus gundi), apparently divides in a totally different manner, and 
shows a peculiar disposition of the chromatin. No loose chromatin has 
been observed. Until further observations have been made this 
parasite cannot be included among the true Piroplasma. 
Further observations are needed before the position of the other so- 
called Piroplasma can be determined. 
The expenditure entailed in the prosecution of our investigations on 
piroplasmosis has been largely defrayed by grants from the Govern¬ 
ment Grants Committee of the Royal Society. 
REFERENCES. 
Christophers, S. R. (1907). Piroplasma cams and its life cycle in the tick. Sci. 
Mem. by Officers of the Med. and Sanit. Depts. of the Govt, of India, N.S., No. 
xxix. 83 pp. 3 pi. Calcutta. 
Gonder, R. (1906). Achromatous vesperuginus Dionisi. Arh. a. d. Kais. Gesund- 
heitsamte , xxiv., pp. 220—226, pi. iv. 
Dionisi, A. (1899). La malaria di alcune specie di pipistrelli. Ann. d’ Igiene 
Sperimentale , N.S., vol. ix. 41 pp. 2 pi. (reprint). 
Fantham, H. B. (viii. 1906). Piroplasma muris, Fant., from the blood of the white 
rat, with remarks on the genus Piroplasma. Quart. Journ. Microsc. Sci., vol. l. 
pp. 493—516, pi. 28. 
- (v. 1907). The chromatin masses of Piroplasma bigeminum (Babesia bovis), 
the parasite of Texas cattle-fever. Ibid. vol. Li., pp. 297—324, pi. 18 and 
text figs. 
Nicolle, C. (xi. 1907). Sur une piroplasmose nouvelle d’un rongeur (Ctenodactylus 
gondi). Arch, de VInst. Pasteur de Tunis, iv. pp. 216—218, and text figs. 
EXPLANATION OF PLATE XI. 
Multiplication of P. canis. Examples taken from a single blood-film. Photomicro¬ 
graphs, x 3000. 
Figs. 1, 2 correspond to Figs. 8—10 in Diagram I (p. 136). 
Figs. 3, 4 correspond to Fig. 12. 
Fig. 5 corresponds to Fig. 13. 
Figs. 6, 7 correspond to Figs. 7, 8 in Diagram 36 (1907, p. 262), and each illustrate the 
simultaneous division of two parasites in a corpuscle. 
