NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
46 Scientific Memoirs by
carcase examined completely. It attaches itself to the mucous membrane in
exactly the same manner as is done by the Trichocephali, the head tunnelling
just below the epithelium for some little distance, while the tail hangs free. It
is almost impossible to detect it in the primary examination of the intestine ;
requiring careful examination of the mucous membrane under the simple micro-
scope.
The easiest way to find it, however, is to wash a certain length of intestine
which has soaked for some hours in carbolized water, rubbing it well between the
fingers and to examine the washings by transmitted light. From the numbers
I have obtained by washing a comparatively small portion of intestine, I should
say that they are often present in enormous numbers.
Its close resemblance, in all save size, to S. contortus, the common sheep
maw-worm, cannot be overlooked. Dr. Curtice 1 g i v e s a n e x c e l l e n t d e s c r i p t i o n
and plate of S. contortus, but neither figures nor describes the cervical alæ de-
scribed by Diesing in his diagnosis of the species. It is, however, present
in a large proportion of the specimens in my own collection, though it is seldom
wide enough to merit Diesing's epithet of " semi-elliptical." Its presence, how-
ever, adds a new resemblance to S. colubriformis,t h e m i n u t e s p e c i e s a t p r e s e n t
under consideration, though I am by no means sure that it is uniformly present
in that, even in females.
The determination of this point is rendered difficult by the fact that they
are only visible when the worm is lying, so that they project ; when half turned
round they cannot be seen at all ; and this is the very position in which the
worm naturally lies.
It might therefore be suggested that the present species is merely a
younger stage of S. contortus, but the circumstance that all the specimens
examined were sexually mature tells strongly against such a supposition. Their
habitat again is different, and no specimens of intermediate size could be dis-
covered, either in the stomach or intestine.
The present species too wants the peculiar flap guarding the vulva, so
characteristic of S. contortus.
Another, and I think conclusive, point is that the ova of the smaller species
are considerably larger than those of S. contortus and also differ somewhat in
shape, those of S. colubriformish a v i n g a n e l o n g a t e d e l l i p t i c a l o u t l i n e , w i t h
almost symmetrical poles, while the ova of S. contortus, though about the same
width, are stouter and ovate, one pole being distinctly blunter than the other.
The size of nematode ova is very constant for the same species, and seems
constant through all adult stages of the same worm, so that it forms an excellent
specific character. This is very noticeable in the cases of Dochmius duodenalis,
and Sclerostomum tetracanthum. In dimensions and appearance the free, or
rhabditis, stages of these species, which I have recently described, are about
L o c . c i t .
Medical Officers of the Army of India.
47
as dissimilar from their entozoic stages as any two nematode species can well
be. In each case, however, the ova, whether produced by entozoic, or free-stage
worms, are microscopically identical.
I think, therefore, that there can be no doubt that S. colubriformis will be
found to be a good species ; and I have little doubt that it will be ultimately
found to have a tolerably wide distribution, as I believe that it is entirely owing
to its minute size that it has hitherto escaped recognition.
Although it certainly attaches itself by penetrating the intestinal mucous
membrane, it may be doubted if its presence can have any great pathological
significance, the small size of, and absence of, armature to the mouth being
against the supposition that it has any leech-like propensities, though, at the
same time, its dark colour would somewhat countenance such a view. The
possibility of it working much harm seems to me to depend entirely on this
point, as, if it be a blood-sucking species, very large numbers might quite com-
pensate for its small size, and rapidly produce a destructive anæmia.
In the probable absence, however, of any such habit, the most it can be
credited with is an aggravation of the dyspeptic symptoms brought about by the
presence of other and more formidable species.
Before quitting our consideration of this worm, I may as well note the
very peculiar structure of the female generative ducts. The vulva opens into
the middle of a sort of cylindrical sac, which extends for a short distance for-
ward and backward from the vaginal opening. The peculiar point is that the
connection between this vagina and the uterine canals is effected by means of a
thick, chitinous, valvular apparatus, which closely resembles the œsophageal bulb
of certain nematodes, and, on high power examination, is seen to be of a most
complicated structure, the chitinous lining of the vagina projecting up into the
end of the lax uterine canal, and having a deeply sinuate margin. Surrounding
this structure is a very thick muscular ring, which gives the bulb-like outline to
the whole apparatus. An exactly similar structure is faintly outlined in Curtice's
figure of S. ventricosus, though he makes no special mention of it in his text ;
and something similar is also to be made out in S. contortus, though the bulb is
proportionally much smaller and weaker, being scarcely more than a thickening
of the muscular coat in this situation.
Trichosomum verrucosum, sp. n.
This species, which also appears to be hitherto undescribed, was found in
the stomach of a sheep at Shillong, a few being found in each division, except
in the reticulum. It seemed then so improbable that so comparatively large
and obvious a species should be new that I only collected a few specimens for
identification, and I now find that, without exception, these are females. The
male is probably much smaller, and so escaped observation.
Owing to the want of male specimens the determination of its generic
48 Scientific Memoirs by
position is uncertain. It is even possibly a strongyle, the ova possessing the
broad transparent external zone so characteristic of most members of that family ;
but, on the whole, I prefer to refer it provisionally to the genus Trichosomum,
more specially as I found attached to one of my specimens a portion of the
male generative organ ; and this had a curiously echinate sheath, such as is
characteristic of many members of that genus.
Description. —Female, about 9 c. m. long (3½ inches). Somewhat tapered
alike at head and tail ; but elsewhere uniformly about 0.5 mm. in thickness.
The mouth is unarmed, and surrounded by six blunt The œsophagus
is soft and thin-walled. The skin of the head, and first half inch of the body is
thickly beset with irregularly shaped, flat verrucosities, which, however, involve
only the cuticular layer.
The female generative opening is situated about 2 mm, in front of the
caudal extremity ; the otherwise symmetrical uterus on one side making a caudal
loop below it, about half-way to the anus, which is situated immediately in
front of the caudal extremity, which ends in a curious, finger-shaped process,
bent towards the ventral aspect. The uteri are so large that the mature worm
seems little else than an elongated sac of ova. The ova (intra-uterine)
measure 0.05 mm. in length by 0.027 mm. in width, and are regularly oval in
outline with a broad transparent zone and thin external envelope.
The most advanced specimens contained a pear-shaped embryo bent on
itself.
Note on Steongylus ventricosus, Rud.
While on the subject of ovine parasites, it may be well to note that it is
difficult to reconcile the original description of this species with the description
and figure of the species which Dr. Curtice1 i d e n t i f i e s b y t h i s n a m e . R u d o l p h i ' s
species was found in Cervus elaphus, L. and belongs to Diesing's division of
the genus, in which the head is bialate, and the bursa of the male multilobu-
lar, both of which characters, to begin with, are conspicuous by their absence in
Dr. Curtice's species, the exquisite figure of which is obviously too minutely
drawn to admit of any doubt as to its accuracy.
Briefly the differences between the two species may be formulated as
below :—
S. ventricosas, Rud.
Head attenuate with two thin alæ.
Body capillary, about a third from its com-
mencement very thickly ventricose; vulva
near the ventricosity.
Bursa of the male multilobate, radiate.
Length, 6-8 " (13-19 mm.)
Dr. Curtice's species frem American sheep
.
Head cylindrically inflated, with no alæ.
Body " comparatively stout ;" vulva about
two-ninths to one-third of the entire
length of the female from the tail.
Bursa conical and bilobed, the ventral mem-
brane being narrow the dorsal wide.
Length : male, 6 mm., female, 13 mm.
It will thus be seen that, beyond a superficial resemblance, the only common
1 Loc. cit., p. 149.
Medical Officers of the Army of India.
4 9
character is the marked ventricosity of the neighbourhood of the vulva, which,
however, is differently placed in its relation to the length of the body.
It is obvious then that Dr. Curtice's species is distinct from S. ventricosus'
Rud. Might I suggest that it should be named S. Curticii?
It is obvious that this species is very closely allied to that I have just
described as S. colubriformis.A t f i r s t I t h o u g h t t h a t t h e y m i g h t b e i d e n t i c a l ,
but the absence of alae and the cylindrically inflated head, it seems to me, should
be sufficient to distinguish them. Moreover, the male burs, though very much
alike, differ in certain particulars, and I have not been able to find any trace of the
peculiar dotted appearance of the skin, which is prominently noticed alike in his
description and figure. Further, I have never met with a single female which,
by any straining of terms, could be said to be ventricose. At the same time
I do not consider the question can be considered as quite settled until actual
specimens are compared.
G. M. GILES, M.B., F.R.C.S.,
Surgeon, Indian Medical Service.
SANAWAR :
The 26th November 1891.
Explanation of Plate
Strongylus colubriformis, sp. n.
FIG. I. Male x 30 diameters.
„ I a. „ natural size.
„ 2. Female x 30 diameters.
„ 2 a.
„ natural size.
„ 3. Male bursa spread, x 170 diameters.
„
4.
„ copulatory spicula x 170 diameters.
„
5.
„ bursa viewed somewhat obliquely, from the ventral aspect x 17 diameters.
„ 6. Anterior extremity of female x 440 diameters.
„ 7. Vulvar portion of body of female x 130 diameters—
a—vulva.
bb—valvular apparatus, guarding the mouths of the uteri.
The darkly shaded portion represents the intestine.
„ 8. Caudal end of female x 170 diameters.
„ 9. An ovum (from uterine cavity) x 440 diameters.
Reg. No 696. San., I.—Mar. 92.—301.
Litho., S. I. O., Calcutta.
A Contribution on the Life History of the male Filaria me
d - i n e n s i s
founded on the Examination of specimens re-
moved from the abdominal cavity of man.
BY
SURGEON R. HAVELOCK CHARLES, M.D., M.CH., F.Z.S.,
BENGAL MEDICAL SERVICE, PROFESSOR OF ANATOMY AND COMPARATIVE ANATOMY, MEDICAL COLLEGE, LAHORE ;
SURGEON, MAYO HOSPITAL, LAHORE ; FELLOW OF THE PUNJAB UNIVERSITY.
THE specimens of which the accompanying sketches are fairly faithful
representations were removed from the sub-peritoneal tissue of " subjects" un-
dergoing dissection in the Anatomical Department of this College. Figures 1,
2 and 3 represent the calcified remains of specimens of Filaria medinensis
in various stages of development. These came from one " Subject," and
were found in the neighbourhood of the R. Ext. Iliac Vein. The largest
was lowest down, the smaller ones being near the R. Sacro Iliac Art. The
l e ngt h of Fi gur e 1 I c omput e t o be a bout 266 mm. a nd i t s di a me t e r 1. 8 mm.
The smallest specimen, Fig. 3, did not measure, previous to undergoing calcifi-
cation, more than 30 mm., and its diameter is 0.5 mm. It may have been
on its migration from the alimentary canal some time, so that its size on
escaping from the intestine was probably very much less than the foregoing
measurement. The cellular tissue around was thickened as if it had been
the seat of old inflammation. The calcified remains are each surrounded by a
sort of boundary membrane, which evidently, on the subsidence of the in-
flammation, closed them severally off from the general economy. Why the
worms died it is impossible to say. It is probable that, if the host suffered
from continued fever of a high temperature, their vitality may have been inter-
fered with and their destruction ensured. Enlarged spleen was present, thus
showing that the host had in his time been a malarial subject. The worms
having died, the deposition of lime salts in their tissues is easily understood.
This calcification has left beautiful casts of the worms, demonstrating well
the rounded shape and the calibre of the body. Neither head nor tail can be
made out. I consider there is no doubt that the specimens represent imma-
ture guinea-worms. My reasons for considering them so are
(1) Shape of body proves them round worms, Nematoda ;
(2) The calibre, 1.8 mm., and length, 266 mm, (about), agrees with that of Filaria m. ;
H 2
Scientific Memoirs by
(3)The Eustrongylus Gigas has a similar length, but its calibre is much greater, and,
moreover, it is very rare in man : the kidneys also of the " host " were not
diseased ;
(4)The finding of uncalcified specimens (Figures 4 and 5) of guinea-worms in another
" subject " a few weeks later confirmed the suspicions I already had of the
affinity of the calcified parasites.
Figures 4 and 5 are drawings of Nematoda taken from near the attached
portion of the mesentery from out of the sub-peritoneal tissue—in the vicinity
of the Ileo-cœcal valve. I regret the specimens were injured on remov-
al. The remains of the largest—Figure 4—1 have joined together, and so
obtained a sketch of a worm presenting all the characteristics of Filaria
medinensis. On examining two (there is only a drawing of one of these—
the second unfortunately was placed in spirit and hence spoilt—that of which
the drawing is made was preserved in glycerine) I was struck by seeing some-
thing growing from the side of each of them. This "something" I found to be a
round worm with the characters of that to which it was attached. On drawing
upon it with a forceps I found, to my astonishment, that it was possible to pull
it out of the body of the larger worm from a small opening near its middle
(thus showing that it was not a case of a worm with a bifid body). I did not
completely pull it out, and only withdrew it about 1 cm. I was then of the opi-
nion that I had found a male and female round worm in the process of copula-
tion and at the same time that I had discovered the long sought for male Dra-
-cunculus ! The female (Figure 5 b) was 148 mm. long and 1.2 mm. in
diameter: the posterior extremity of the body, however, was broken off. The
male (Figure 5 a) was much smaller and somewhat shrivelled, though showing
in every way the peculiarities of a separate individual Nematode. Want of leisure
compelled me to place my specimens aside. This I did, preserving the frag-
ments of one male and female (Fig. 5) in glycerine and of another male and
female in spirit. A single large female (Figure 4) I placed in glycerine. This
was in March last. Furlough to Europe has prevented me prosecuting the subject
further at an earlier date. The specimens have suffered somewhat, but even now
the male and female in copulation (Fig, 5) can be well seen, though the male
has been considerably injured. No embryos or ova can be made out. It can-
not be expected, however, that embryos should be found, as the ova would not
be fertilised, or rather the embryos would not be freed from the ova till some
time after fertilization, which was just in progress. The head with the mouth
can be seen. There seems to be a dilatation behind the mouth ( pharynx).
The tubercles on the head are shown in Fig. 6, which -figure also illustrates
the character of the muscular pharynx. The mucronate tail is well marked
in Fig. 5. Under a low power the transversely striated cuticle covering a
muscular body is apparent. The tail of the male is in the body of the
Medical Officers of the Army of India
53
female, and hence cannot be seen ; otherwise, the characters of his body are similar
to those of hers.
I shall now briefly trace the life history of the guinea-worm. Beginning
with the female, heavy with young, drawn from the body of the human host by
the itinerant barber, who ignorantly casts the extracted worm on the ground,
where the decomposing body gives issue to thousands of living embryos. These,
gaining water by means of the wind or rain, migrate (according to Fedschenko)
into the body of a cyclops, upon which they become parasitic, becoming coiled
up within its limbs (" as many as 6 or even 12 of the parasites being occasionally
found within the body of a single crustacean host "), and reaching there full larval
growth. A human being drinks the water containing the infected cyclops. The
juices of his intestine, digesting the Entomostracan, liberate the matured larv
æ —
m a l e
a n d f e m a l e .
R a p i d g r o w t h t a k e s p l a c e i n t h e s e . T h e m a l e s a t t a c h
themselves to the females, both leaving the intestine together for the safer
retreats of the retro-peritoneal tissues. The exodus probably occurs where
the mesentery is attached to the bowel—the planes of peritoneum forming the
mesentery directing their course in the sub-peritoneal connective tissue to the
back of the abdomen in the neighbourhood of the Jumbo-sacral articulation,
where, in a nidus, well-nourished by the abundant blood supply, the female para-
site can remain at ease and grow at leisure, unaffected by the contractions of
muscles, and undisturbed by surface chills. She increases in size from the growth
of her uterine organs. The poor male, gradually diminishing, comes to appear
only as an appendage to his mate—having completed the task allotted to him—
that of fertilising her.
The time the female remains in these internal regions will vary according
to the state of development of her contained embryos. On maturation the
wandering again takes place—may be down on the Psoas under Poupart's
Ligament, being guided by the muscular planes to " point" on under surface of
the deep fascia in some region of the thigh or leg, just as a Psoas abscess may
" point " either in the inside of thigh or as low as side of ankle ! A more
posterior exit from the abdominal cavity—that by the Gt. Sciatic Notch in
company with the Sciatic Ns. and Vs. to the buttock—would lead the wanderer
down the back of thigh to calf by way of the Popliteal space. Having arrived
under the deep fascia, it would act as a foreign body. Interfering with the
proper contraction of the muscles, the irritation of its presence would cause an
abscess by which the imprisoned worm would be liberated. The male dies in the
sub-peritoneal tissues, the female finishes her course on the surface of the body!
In the life history and morphology of the Filaria medinensis certain points
are up to this doubtful or unknown. As (I) Where does the impregnation of the
female occur ? (2.) What becomes of the male ? (3) How is it that no sexual
.orifice has been discovered on the body of the female?
54
Scientific Memoirs by
Claus (Sedgwick's Translation, 1889) says, "Whether they first escape" ( i.e.,
from the body of the cyclops) " and copulate in a free state is not known."
Cobbol d (1879) says, " It i s probabl e t hat sexual mat uri t y i s next acqui red
within the human stomach, copulation following." Granting that the specimens
found by me are male and female guinea-worms, Cobbold's view would be
correct. This learned Helminthologist a little further on says, " The females
migrate to the situations in which they are found beneath the skin of the human
bearer, whilst the male perishes and passes out with the fceces. " The italics are
mine. This, however, is not so. The female pierces the wall of the intestine
accompanied by the male, which remains attached to her body till impregnation
be fully accomplished. Then dying, his body, gradually shrivelling up, would not
be discovered when the female had reached her host's skin. Copulation in this
instance is a slow process. The male is, as it were, a parasite on his paramour,
and being attached to her genital aperture (as in parallel cases amongst the
lower Crustacea) gradually wastes away in the delights of love ! This explains
why the male has not been discovered with the adult female on her arrival at the
body surface. Although no sexual orifice has been found on the adult, yet such an
opening may be seen on the young form after it leaves the intestine, as, at that time,
its uterine organs are not distended with crowds of microscopic embryos, causing
almost an obliteration of the perivisceral cavity. The Vulva is small in comparison
to the size of the worm, and is only used for impregnation, not parturition : there-
fore, as development proceeds—there being no necessity for its presence—it
would degenerate and diminish as the body swelled from the contained embryos.
But if the parasite be discovered in the neighbourhood of the mesentery—that
is, soon after its start on its journey—and a second parasite be found attached
to the side of the larger, out of an opening on which it can be withdrawn, are we
not justified in saying that the orifice in the larger worm is a genital aperture,
and that the attached worm, which was withdrawn out of this aperture, is the
male parasite ?
The reason why the male form has not before been met with, I think, is pro-
bably due to the fact that it is only likely to be found on a dissection of an
imfected subject, and not merely on the post-mortem examination of a body
containing the parasites in the regions in which I discovered them. The male
wastes and becomes small, having impregnated the female. He dies in the
abdomen, and his attached remains in all likelihood would be lost owing to the
friction of the tissues on the body of the female during her progress down the
extremity.
The discovery of comparatively large females, and of males and females to-
gether, in the abdomen practically proves that infection with this parasite takes
place by the alimentary canal, and finally disposes of the old idea that the para.
site could gain entrance by the skin of the extremities or back. It passes from
within out, NOT from without in.