On a new Sclerostome from the large intestine of mules (a
postscript to the preceding paper).

BY

SURGEON G. M. GILES, M.B., F.R.C.S.,

INDIAN MEDICAL SERVICE.

      SINCE writing the above, a more careful examination of the materials ob-
tained from the mules that died in the so-called epizooty of " Surra " at Shillong,
has resulted in the discovery that the larger worms, found so abundantly in
company with Sclerostomum tetracanthum, are not, as I supposed, all large
specimens of that species, or of Sclerostomum equinum (Rud.), but examples of a
species which has not, so far as I can discover, been hitherto described.

      Although they never rivalled S. tetracanthum in abundance, they were yet
so numerous that reflection should have shown that no large proportion of them
could be examples of S. equinum, as thousands must have been present in several
of the cases, and, to account for so large a number, the mesenteric arteries should
have been a mass of aneurisms; whereas, in only one case, were these found,
and in this only two small ones, which could hardly account for the presence in
the intestine of more than a score or so of the mature parasites.

      The species I am about to describe is intermediate in size between S. equi-
num and S. tetracanthum, averaging scarce half the length of the former, but is
proportionally very stout, and the characters of the mouth armature, and of the
bursa copulatrix are quite sufficient to establish its specific distinctness. As,
however, the three species are closely allied to one another, I append descrip-
tions, with original figures, of the other two, in order that their differences
and resemblances may be the more exactly appreciated.

      The new species is a vicious blood-sucker, and was always found gorged
with blood, and generally firmly fixed to the mucous membrane. A very large
proportion are always to be found firmly joined together in pairs in copula, the
grip of the male hood being assisted by a glutinous secretion, so that it takes
some little careful dissection to separate them. As, in size, it bears at least as
large a proportion to the bulk of a horse or mule as Dochmius duodenalis
does to that of a man, and as it is often present in even larger numbers, it must be
capable, by mere depletion, of doing incalculable harm to its host, and it may be
doubted whether the caseous infiltration of the intestines brought about by

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