C. C. Dobell 
291 
In some of these large forms the nucleus had undergone partial 
fragmentation (Fig. 10), but I believe that this was the result of 
degeneration. 
Certain of the parasites were distinguished by the possession of a 
very well-developed sheath (cytocyst), which stained a bright pink 
with Giemsa (Fig. 11). In other corpuscles I frequently found empty 
sheaths (Fig. 12), from which the parasites had evidently escaped. Free 
forms were also seen in the blood plasma (Fig. 13), and probably repre¬ 
sent animals which have left their sheaths behind. The free forms 
attained a length of about 17 y. 
I found doubly infected corpuscles on several occasions. No para¬ 
sites were seen in the leucocytes. 
From these facts it appears probable that the parasite enters a red 
blood corpuscle as a very small, falciform sporozoite or merozoite. In 
the corpuscle it grows into either a long or a stumpy organism—subse¬ 
quently developing into a large fat form. It is possible that these two 
forms are sexually differentiated, and the large animals are possibly 
gametocytes, but this is merely conjectural. 
At a certain period the parasite (? both forms) may envelope 
itself with a sheath (staining pink with Giemsa), from which it can 
subsequently issue. The significance of this is unknown. 
I never found any forms which could be regarded as undergoing 
schizogony. Multiplication had probably ceased at this late stage of 
infection. 
Details of structure will be readily seen by referring to the figures. 
It will be unnecessary for me to describe them more minutely here. 
II. Haemogregarina sp. from Python spilotes. 
(Plate XX, Figs. 14, 15.) 
I obtained this organism from an Australian Python. It is perhaps 
the same as Danilewskya pythonis Billet 1895 (= Haemogregarina 
pythonis Labbe 1899) and II. shattocki Sambon 1907. Possibly H. 
pococki Sambon 1907 is another synonym. The haemogregarines of 
pythons have already been described by Billet 1895, Prowazek 1907, 
Sambon 1907 and Laveran 1908. 
My organism is a typical haemogregarine (Figs. 14, 15) and shows no 
trace of the “ blepharoplast ” described by Prowazek. All the forms 
which I found were in approximately the same stage of development. 
