Medical Officers of the Army of India.

15

generative gland; and all stages, from indeterminate Rhabdites still provided with
the hollow styloid mouth armature, to sexually mature parasites, just ready to
escape with a nearly complete dental apparatus are to be found. The speci-
men figured for example, though far from sexually mature, is quite clearly a
female, the generative aperture being already clearly discernible about the
middle of the body, though the generative gland itself, as far as its histiologi-
cal elements are concerned, might be either testis or ovarium. In spite of this,
taken as a whole, the sex of the animal might be diagnosed from an exami-
nation of the gland alone, for the most advanced cells are placed in the middle
of the organ and not at the aboral extremity, as would be the case in
a male histologically indeterminate gland.

      While encysted, the little worm undergoes several changes of skin, and, by
the time it is ready to escape, is fully equipped with the peculiar mouth arma-
ture of the adult. The buccal cup first appears as a quite unarmed cavity.
Next, the circlet of minute denticles, that comes behind the circlet of fimbriæ
in the adult, is developed. The four labial spines next appear, but are rather
papillæ than spines at this stage; and, finally, the circlet of fimbriæ and the
ring of plates round the pharyngeal opening, made their appearance. Probably
more than one ecdysis is undergone by the worms after escaping from
encystment, for specimens undergoing the process are not hard to find, though
I was unable to satisfy myself of the occurrence of the so-called cocoons de-
scribed by Cobbold.

      Appearances that might be interpreted somewhat in this fashion I have
indeed met with; but they appeared to me to be better explicable as acci-
dental accumulations of fæcal matter round a worm undergoing ecdysis.
Nematodes undergoing this process are always in a very sluggish state, and
so would more readily serve as the nuclei of such concretions than the actively
moving creatures they are when not so engaged; but I must repeat that I look
upon the occurrence as purely accidental, as worms changing their skins were
far more commonly to be found without any such encumbrance than with it.

      Thus it will be seen that, during the life-history of this worm, it inflicts two
serious lesions on the intestine. First, it bores its way into, and encysts itself
within the substance of the mucous membrane, setting up changes which
result in the certain impairment, and often entire loss, of functional activity in
the little patch of digestive mucous membrane affected; and secondly, it, with the
powerful teeth of the fully grown worm, gnaws into the mucous membrane
and continuously sucks its victim's blood, and, as the period of sexual vigour
during which the worm exhibits this blood-sucking propensity is probably a
tolerably long one, this second class of lesion is one which must be again and
again inflicted by the same worm.

      In the face of these facts it appears difficult to understand how any one
can doubt the ability of this parasite to bring about a fatal result.