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Mr Dobell, On the Intestinal Protozoan 
On the Intestinal Protozoan Parasites of Frogs and Toads. 
(Preliminary Communication.) By C. C. Dobell, B.A., Trinity 
College. 
[ Received 19 February 1908.] 
Some time ago, I began an investigation of the life-histories 
of the Protozoa inhabiting the gut of the common frog and toad. 
And although my investigations are far from complete, it has 
become advisable for me to publish my results, as I shall be 
unable to continue the work for some months. I hope before 
long, however, to be able to publish a full account together with 
my drawings — without which my description is of necessity in- 
complete. 
Such as is new, relates chiefly to the smaller Protozoa. I may 
briefly summarise my main conclusions as follows : — 
A. Flagellates. 
(1) Trichomastix batrachorum n. sp. 
This new species is structurally almost identical with pre- 
viously described members of the genus. The body is oval, and 
possesses an oval nucleus at the anterior end. Immediately in 
front of this lies a small chromatic body which I shall call the 
blepharoplast. From the blepharoplast arise the four flagella — 
three directed anteriorly, one posteriorly. Running backwards 
from the blepharoplast, and terminating in the caudal process, is 
an achromatic axial rod — whose function is probably skeletal. 
A cytostome is present at the anterior end of the animal. 
Very large forms of this parasite are sometimes to be found. 
They are further characterised by possessing a very thick axial 
rod. 
Multiplication takes place, in the gut of the host, by longi- 
tudinal division. The first event in the process is the loss of the 
axial rod. This appears to be dissolved and absorbed in some 
way. The blepharoplast then divides, two flagella going to either 
end of the dumb-bell figure which it forms. The nuclear mem- 
brane disappears, and the chromatin granules arrange themselves 
in a spindle-shaped figure round the strand connecting the two 
daughter blepharoplasts. The latter gradually separate from one 
another, the connecting strand increasing in size and remaining 
as a darkly-staining rod. Around the centre of the rod, the 
chromatin granules mass themselves, forming large, irregular, 
chromatic lumps. A division of the chromatin into two masses 
