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about six to seven microns and there are no proteinacious granules present in it
which, they think, were utilised for building up the cyst wall. It is not clear
why they should think that in the host tissue, where food material is available,
the spore should utilise its own proteinacious granules and shrink in size only
to grow bigger again at the expense of the host. It is doubtful if such a thing
happens in nature. Again the size of the young trophozoite is almost that of
the small spore found in an ascus and this observation, therefore, suggests
that the smaller type of spore alone develops into a trophozoite in the host
tissue. The fact that the large spore is provided with proteinacious food
granules and is protected with a fairly thick chitinous capsule at once suggests
that it is destined to complete its life-history outside the animal body, even as a
seed is provided with reserve food material and a testa.
Beatty [1906] considered that the " spore morulae " which are protected
by their envelopes may undergo changes outside the body. Some workers
are of opinion that the small spores in an ascus are degenerate forms, but a
careful examination of such spores shows that each has a nucleus and proto-
plasm, the staining reactions of which do not suggest degeneration. Hence it
would appear that they really are living spores destined to continue the parasi
tic development in the tissue of the host, and the large spores are destined to
complete their biological destiny outside the animal body.
10. ATTEMPTS TO CULTURE RHINOSPORIDIUM
Ashworth [1923] concluded that Rhinosporidium is a fungus and placed
it among the Phycomycetes and this has been accepted by Ramsbottam [1931].
Dodge [1936] quotes Wernicke [1907] and places it among the Coccidioideaceae.
Excepting for a partial success of Rettle, quoted by Ashworth, no one seems
to have succeeded in cultivating the organism on artificial media in the labora-
tory. The fact of the difficulty experienced in cultivating that fungus indicates
the delicate nature of the oraganism. This feature is further supported by the
fact that cases of Rhinosporidium are few and far between being localised only
to certain areas as far as could be gathered from the published records. It is
apparent that the very first case of rhinosporidiosis could have occurred only
from a pre-existing fungus outside the animal body. Further, indigenous
cases of rhinosporidiosis have been reported from countries very widely sepa-
rated from one another, viz., India, Union of South Africa, Philippine Is. and
South America, etc., and for obvious reasons such cases could have received
the infection only from a pre-existing saprophytic form of the fungus in those
localities. Again it is interesting to note that in India rhinosporidiosis is
usually found in the agricultural class of people and in cattle. This fact sug-
gested to the author that in nature a saprophytic form of the fungus probably
germinates and thrives in bovine dung since bovines swallow their nasal dis-
charges and with them the spores of Rhinosporidium when the lesions are in the
nose. The possibility of the large spores being destined for a phase of life
outside the body of the animal has been discussed above. With this idea in
view, a diseased animal was obtained by the author from Tanjore for experi-
mental purposes. This animal had a very small growth, about the size of a