14
Laveran's view who regards these parasites as being allied to the Hœmamœbœ. The name
Leucocytozoon is therefore best retained for the mammalian forms which are parasites of the
white cells alone.
I have again failed to find any extra-corporal cycle in the lice found on Funambuli
pennantii and as all the squirrels were infected no feeding experiments were carried out.
Leucocytozoon fells domesticœ.—This is one of the rarest parasites in Madras ; after exam-
ining 374 cats I have only found it in 9, two of which are now in the laboratory. I have also
failed to find any extra-corporeal cycle in the two ecto-parasites of the cat, Ctenocephalus
felis and Hœmaphysalis fusca ; a long series of feeding experiments are now being conducted and
so far I have excluded the cat flea and it seems that the tick is the most probable transmitter.
There are eight possible ways in which it can transmit the parasite as follows :
—
(1)Through the nymph fed on an infected cat in its larval stage.
(2)Through the adult fed on an infected cat in its nymphal stage.
(3)Through the larva partially fed on an infected cat, being dislodged and finding its way
to an uninfected cat.
(4)Through the partially fed nymph.
(5)Through the partially fed adult.
(6)Through the male tick.
(7)Hereditarily.
(8)Through an uninfected cat eating ticks from an infected cat.
Methods 6, 7 and 8 are for many reasons not likely and the remaining five are at present
under investigation.
Leucocytozoon leporis.—This parasite occurs commonly in the large mononuclear leucocytes
of Lepus nigricollis. In general appearance it is not unlike Leucocytozoon canis and it has a
dense capsule which is resistant to most stains. Its method of reproduction is almost exactly
similar to that of Leucocytozoon funambuli and takes place in the alveolar cells in the lung of the
hare. It is being investigated along similar lines as that of the cat parasite and I hope to give
a complete description of it in due course.
No. VI.
BATRACHIAN HÆMOGREGARINES.
By the SUPERINTENDENT.
Hœmogregarina berestnieffi, Hœmogregarina magra, Hœmogregarina sp.? and Hœmogregarina
minima were found in a large number of Rana tigrina collected from a small pond in Dr. Hen-
derson's 1 garden in Madras ; many of the frogs had a species of leech Clepsina? on them.
This leech was latter readily obtained by holding a frog in the water for a few minutes when
as many as thirty attached themselves to its legs and body. Another species of Hœmogregarine
allied to Hœmogregarine minima has also been found in Rana hexidactyla taken from a large
tank close to the Institute. The small leech could not be found in this tank, but a much larger
species was abundant.
A reference to the literature on Hœmogregarines of frogs shows the fact that except for
Hœmogregarine minima very little is known of their life histories. Hintze has described the
sporogenetic cycle of H. minima which he considers takes place in the intestinal epithelium of
Rana esculenta. I have been unable to find any such cycle either in the species occurring in
Rana tigrina or that found in Rana hexidactyla. I have also failed to trace any connection
between the hœmogregarines and flagellates frequently seen in the Clepsina fed on frogs
infected with Hœmogregarines (vide Appendix VIII). In the intestinal diverticula of the
leech 12 hours after feeding on a frog infected with Hœmogregarina berestnieffi the parasites
leave the red cells and are seen free. On studying these free forms it was found that the
greater part of the long tail-like process figured by Berestnie consists of a loose sheath
and does not contain any part of the parasite ; after 36 hours the parasite leaves its capsule and
then is only about half the size of the characteristic blood form. These free forms are actively
motile.
In the case of Hœmogregarina the mature parasites only leave the red cells after being
ingested by the leech and about 36 hours later they pass out of their capsules and are seen as
long active vermicules.
1 I wish to take this opportunity of thanking Dr. Henderson, Professor of Biology, Christian College, Madras,
for his kindness in identifying a large number of animals used in the Laboratory.