[From the Proceedings of the Zoological Society of London,
June 9, 1857.]

On thk Anatomy of a new Species of Pf.ntastoma found
IN THE Lung and Air-sac of an Egyptian Cobra. By
George Harley, M.D., F.C.S., of University College,
London.

(Annulosa, PI. XLVI., XLVII.)

Having lately had the opportunity of dissecting a fine specimen
of Entozoon, which, as far as I am aware, is an entirely new and un-
described species, a brief description of its anatomy may perhaps
prove interesting to the members of the Society.

The worm which I am about to describe was found in the lung of
the Egyptian Cobra, Naja Hage, kindly sent to me for examination
by D. W. Mitchell, Esq. I was fortunate enough to obtain four
fine specimens, nearly all of equal size, from the same animal. They
measure from 4 to 5 inches in length, and from 5 to 8 lines in cir-
cumference. In external characters they seem to resemble an En-
tozoon found in the lung of a Cobra by Dr. Crisp, a short descrip-
tion of which was given in the Proceedings of the Society for 1853,
p. 22, Annul, pi. 30. fig. 7, by Dr. Baird ; who spoke of it as an un-
described species of Pentastoma, and gave it the name of Pentastoma
annulatum. Dr. Baird's description of the specimen is, however,
very short, and unfortunately incomplete, in consequence of his
having seen only a small specimen, and that even imperfectly, on ac-
count of the most important fact, the head remaining imbedded, and
hidden from view in the lung of the snake. I think it probable,
however, that the animal which he described is one of the same
species as I have obtained specimens of.

External characters.

The body of the entozoon is of a white colour, elongated, cylindrical
and strongly ringed (PI. XLVL fig. I). It begins with a round obtuse
head, attached to the trunk by a short somewhat narrow neck. The
body then gradually widens for the first three lines, where it mea-
sures in the largest specimen (4| inches long) 8 hues in circum-
ference, and from here down to within a few lines of the caudal
extremity, continues of nearly the same diameter. Below this point
it becomes regularly narrower the nearer we approach to the poste-
rior end, which terminates obtusely. The caudal extremity is almost
of the same diameter as the head. The rings which are, as before
mentioned, very strongly marked, commence close to the posterior
part of the head, and for the first three or four lines, gradually in-

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crease ia size and distance from each other. They then continue of
the same relative size and distance apart ('2 Hnes) till within about
half an inch of the posterior extremity, when they again, however,
become smaller and more closely approximated. In all the four
specimens which I examined, the rings were twenty-seven in number,
and where largest, projected nearly half a line from the surface of
the body.

In the fresh specimen, when examined with a pocket lens, the ex-
terior of the rings appeared mottled with faint white-coloured spots.
Thev were and still are quite opaque, whereas the intervening tissue
is so thin and transparent, that the internal viscera can be seen
through it. A number of white bands or cords appear to connect
one ring with another ; the bands are largest in the lateral and dorsal
regions. A dark-coloured line extends along the back throughout
the whole length of the body : this, as I shall afterwards have
occasion to show, is the digestive canal.

On the vmder surface, in the centre and near to the anterior margin
of the head, which is slightly flattened from before backwards, is a
round foramen, the mouth. On either side of this opening are two
depressions, equidistant from each other, each containing a prehen-
sile booklet of a bright yellow colour. These booklets in shape
closely resemble a cat's claw, which can be extended and retracted at
pleasure, and when completely drawn in, the points of them can be
neither seen nor felt. The obtuse posterior extremity has a deep
cleft across it, and on its under surface are two openings, one in
front of the other : the anterior is the entrance to the vagina, the
posterior the anal aperture.

Anatomy of the Entozoon.

Parietes. — The whole body is invested with a delicate, smooth,
transparent cuticle, which can be readily detached by slight mace-
ration. Beneath the cuticle are two layers of striated muscular
fibres (PI. XLVII. fig. 13), a vertical and a transverse layer; — the
longitudinal fibres are by far the most developed ;— the circular are
in some places entirely wanting. The projecting rings, on the other
hand, are not composed of striated muscular fibres, but consist of
fibro-areolar tissue. They seem to serve as fixed points of action
for the longitudinal muscles ; appearing to supply, in fact, the place
of a hard skeleton. The interior of the abdominal cavity is lined
by a fine transparent membrane, on which I thought I could detect
a single layer of delicate pavement epithelium.

Digestive Systejn.~T\\e alimentary canal, in consequence of its
peculiar dark saffron tint, is readily traceable from its commence-
ment to Its termination. It begins at the mouth, and runs in an
almost perfectly straight line to the opposite extremity of the body,
terminating, as was before mentioned, immediately behind the orifice
ot the vagina (PI. XLVI. fig. 4, a). Close to its commencement
It IS ot the diameter of a fine crow-quill, and may be said to continue
01 nearly the same size throughout its whole course. It lies directly

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in front of the ovary and great nerves, and is almost entirely con-
cealed from view by the innumerable tortuosities of the oviduct.
It has four distinct coats, an internal mucous, an external serous,
and two muscular layers, one running vertically and the other hori-
zontally ; both of which consist in great part of the striated variety
of muscular fibres *. The interior of the aUmentary canal is marked
by longitudinal rugae, from the surface of which long pyriform villi
project.

Nervous System. — The distribution of the nervous system of this
highly organized Entozoon is, in some respects, identical with that
found in the Linguatula tcenioides, so beautifully described by Pro-
fessor Owen. The large ganglion, or brain, is situated close to the
mouth, and is intimately connected with the cESophagus, to which it
seems to send two filaments (PI. XL VI, fig. 4, b). I could not,
however, satisfy myself of the existence of an oesophageal ring.
The distribution of the large pair of nerve cords, which extend almost
throughout the whole length of the body, differs very materially from
that found in the Linguatula teenioides ; for, after passing over the
fallopian tubes, instead of running down the sides of the ventral
aspect of the body, they continue along the dorsum, behind the ali-
mentary canal and close to the ovary (PI. XLVI. fig. 4, c). They
are at last gradually lost sight of a few lines above the anus.

Organs of Reproduction. — In attempting to describe the organs
of reproduction in this animal, I shall begin at the vagina and trace
them gradually upwards, for it was by following this course that I
was enabled, with the aid of the microscope, to distinguish the dif-
ferent organs, and to ascertain the function of their various parts.

The orifice of the vagina is situated immediately in front of the
anal aperture (PI. XLVI. fig. 4, d). The vagina itself is about the
thickness of a pin, and from 3 to 6 lines in length ; it gradually
widens out into the oviduct, or more correctly speaking, the uterus
(PI. XLVI. fig. 4, e). For about the first 6 inches the uterus has
a greater diameter than the alimentary canal ; it then however be-
comes gradually narrower, till its diameter does not exceed that of
a fine knitting-needle, and continues of this size till withm a few
lines of its termination, where it contracts still more. At its upper
point of attachment, which is opposite the third or fourth ring, its
diameter is not greater than that of the vagina. In two of the speci-
mens I measured the length of the uterus, and found it to be
40 inches from the orifice of the vagina to the place of its attachment
opposite the third or fourth ring. Thus it is seen to be nearly ten
times the length of the entozoon in which it is coiled up. Although
it conceals the alimentary canal, it is not, as in the case of the Lin-
gtiatula tcenioides, coiled round it ; neither has it the ferruginous
tint spoken of by Owen as belonging to the oviduct of the latter
species. It is, on the contrary, of a pale straw-colour when full of
ova, and almost quite colourless when empty. Its parietes are thin

* Ficinus and Valentin found indistinctly striated muscular fi!)rcs in the human
stoniuch.

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and transparent, and when viewed with the microscope are seen to
be muscular, both longitudinal and circular fibres being distinctly
visible. They consist of the non-striated variety of muscular fibre
(PI. XLVII. fig. 14). The fully developed ova are not attached to
the parietes of the uterus by any connecting cellular substance, for
on being cut across, the ova immediately flow out, and the parietes
collapse. On the other hand, the imperfectly developed ova found
in the upper portion of the uterus have a darker colour, and seem to
be adherent by a glutinous material not only to each other, but also
to the walls of the organ.

At the upper point of its attachment to the abdominal parietes
are two oblong bodies of a dull white colour (PI. XLVI. fig. 4,//).
These bodies open directly into the uterus. On examination they
were found to be filled with spermatozoa in all the various stages of
development, from the primitive granule up to the perfectly formed
spermatic filament (PI. XLVII. fig. 8). The filaments are of con-
siderable length, and are amassed together in bundles of tolerable
size (PI. XLVII. fig. 8, a). Some of the fully formed spermatozoa
with large heads measured mm. in length, and a few were even
longer still.

A question of great interest and importance might be here raised
regarding the special function of these oblong bodies, which, as I
have just mentioned, contain innumerable spermatozoa in various
stages of development. Are they the spermatheca or copulatory
pouches of a female ; or are they to be regarded as the testicles or
male organs of generation of a hermaphrodite ? I shall defer the
consideration of this important point until after I have terminated
the description of the animal.

The organs just alluded to, which, for the sake of brevity, I shall
speak of as testicles, are attached to the parietes of the entozoon
by strong bands of striated muscular fibres. At the upper part of
their point of union, the uterus divides into two fallopian tubes,
which gracefully curve round the digestive canal, pass behind the
two great nerve cords, and after getting between them, reunite to
form the ovary (PI. XLVI. fig. 4,ffff). The ovary is of a ferru-
ginous colour, intimately attached in the mesial line to the dorsal
aspect of the animal, and continued downwards between the nerve
cords and behind the alimentary canal to within about 5 lines from
the anus, where it suddenly termhiates in a blind sac.

When viewed through a lens, the coats of the ovary are seen to
be thin and transparent, and not closely surrounding their contents.
They are here and there thrown into loose folds, and the ova can be
distinctly observed in their interior, like a series of bunches of grapes
closely strung together (PL XLVI. fig. 5). When the ova are highly
magnified, they are recognized to be sj)herical bodies attached to-
getlier by little peduncles, and to consist of a tunic or yelk-sac, a gra-
nular yelk and a germinal vesicle. I even detected in many of them
the germinal spot (PI. XLVI. fig. 6 d.).

On tracing the development of the ova, I found that the germinal
spot disappeared from them as soon as they had passed out of the

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fallopian tubes into the upper attached portion of the uterus, — no
doubt, in consequence of the ova having been impregnated during
their transit through that portion of the uterus into which the
testicles open as already described. From this point downwards
the progressive development of the ova can be readily followed. But
as this communication has already extended beyond the limits I had
marked out for it, instead of giving my readers a detailed descrip-
tion of the process of development, I shall take the liberty of refer-
ring them to the accompanying figures, which accurately represent
the different appearances observed in the ova from the time of their
exit from the ovary till their arrival in the vagina (PI. XLVI. fig. 7,
PI. XLVII. figs. 9, 10, 11 and 12). I may here only further re-
mark, that impregnation evidently takes place from above down-
wards, and that no spermatozoa in any stage of development could
be detected in any part of the uterus ; thus forbidding the idea of the
animals having received the vivifying fluid from a separate male
organ after the uterus had been filled with ova.

Having now completed my remarks upon the anatomy of the en-
tozoon, I shall proceed to say a few words upon the important ques-
tion of its sex, and I may premise these words by observing that it
appears to me that some naturalists are at present running to extremes
in attempting to find separate sexes in all animals, and to prove that
there is no such thing as hermaphroditism in nature. Ultra views
are at all times to be condemned, and I think in no case more so
than the present, when the obstacles besetting the path to a definite
conclusion are as complicated as they are numerous. A few years
ago several members of the genus Pentastoma were regarded as true
hermaphrodites by the most distinguished naturalists ; and now since
some of the species have been ascertained to have separate sexes, a
recent writer has ridiculed the idea of a single example of this large
genus having male and female organs of generation united in one
individual. I do not intend to say that he has erred in jumping too
hastily to his conclusion, but merely to remark that the entozoon
which I have described in the foregoing pages, if not strictly belong-
ing to the genus Pentastoma, is yet in many of its characters very
closely allied to it, and that it still remains to be shown that this
animal is not a hermaphrodite. As there are two sides to every
question, and as it is wrong to give an opinion before both have been
examined, I shall briefly state my reasons for thinking it possible that
the animal we have just been considering is a female, and that the
true male organs of generation are to be sought for in another indi-
vidual.

The Linguatula tcenioides, which is the nearest allied species to
my entozoon, was described by naturalists of the very highest stand-
ing, such as Owen, Valentin, Von Siebold, Dujardin and others, as a
hermaphrodite, in consequence of their finding that it possessed, in
each individual, organs containing the female and organs containing
the male reproductive materials in different stages of their develop-
ment ; and that these organs were not only so arranged as to allow
of the vivifying contents of the one coming into contact with those

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of the other ; but that a common canal resulting from the union of
the channels through which the ova from the female and the sper-
matic filaments from the male organ passed, contained the fructified
result of such a reunion, as that of the opposite sexes could alone
secure.

The presence of a product in an organ, however, not being suffi-
cient to ensure that it was produced by, and not introduced into,
that organ, the questioii naturally arose in the minds of some, whe-
ther we were justified in regarding the organs in the Linguaiula
tcenioides containing the ova, as ovaries, and those containing the
spermatozoa as testicles. At first some doubted, and at last others
have denied, the reunion of the sexes in this species of Pentastoma.

VanBeneden, the champion of the latter class of naturalists, states*
that in four examples of the species of Linguatula de Diesing"
and in two others of another kind found in the lung of a Boa, he
ascertained the male and female organs of generation to be in differ-
ent individuals, and that Owen, Valentin, Von Siebold and others,
have erred in describing the L. tainioides as a hermaphrodite. He
describes the testicle in the male as being about \ of the length of
the body, and lying behind the alimentary canal, consisting of a
pouch with thin parietes, terminating behind in a cul-de-sac. From
the upper part of the testicle branch off, two vasa deferentia, and
from the end of each, floats an organ which he looks upon as a pro-
state. These open into round vesicles constricted in the middle,
each contaming a coiled-up tube, which he describes as a penis.

I have quoted Van Beneden's description of a male Pentastoma,
because in the nasal fossa of the Cobra, from which I obtained my
four specimens of entozoa, I found two small Pentastoma of about
\\ inch in length (PI. XLVI. fig. 2) ; and on dissecting one I found it
to agree in every respect with Van Beneden's description of the male
Linguatula. The question then occurred to me, whether or not I
might look upon them as being two males and my large specimens
four females of the same species. The two small entozoa found in
the nasal fossa look exactly like some other Pentastoma which I ob-
tained from the cellular tissue of a Morocco Cobra. Even taking
into account the fact that the male is often much smaller than the
female entozoon, their external characters and apparently their mode
of life are so very different from those of the large worms found in
the lungs, that I can scarcely believe them to belong to the same
species of animal. Even admitting that they were the males of my
large entozoon, I do not see how they could get their spermatozoa
into the spermatheca of the large animals. Van Beneden says he
found an opening for the penis to get out immediately behind the
mouth, but then this organ, which he calls the penis t, is only a few
hnes in length, and consequently could project the seminal fluid hut
a trifling way up the uterus, which, as before mentioned, is 40 inches
long. The pouches containing the semen are situated too at the

* Ann. (Ics Sciences Naturellcs, 3me serie, tome 11-12, p. 325.
T 1 examined what he look for the penis, anil I have some doubts if it, or
rauier tliey, for there are two, are really what he supposes them to be.

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very top of this immensely long duct. It may be said that the
spermatozoa could find the way up themselves. That I admit might
be the case if they were fully developed, and consequently moving
filaments ; but it would be impossible for them to get up in the un-
developed condition in which some of them are found in the pouches.
Besides this, if they were injected into the vagina, why did they not
impregnate any of the ova on their passage up? Impregnation is
distinctly seen to have taken place from above downwards, not from
below upwards, or in any irregular manner.

The only satisfactory way of accounting for the presence of sper-
matozoa in different stages of development in the copulatory pouches,
supposing that they were not generated there, would be to find a
channel by which they might enter without having to pass through
the 40 inches of oviduct. Now I have carefully searched for such a
channel and can find no trace of one. Neither can I find any open-
ing into the animal near to the spermatheca except the mouth, and
I do not think any one will consider that a likely door for them to
enter at.

I admit that my not being able either to detect a tube or an open-
ing into the spermatheca does not incontrovertibly prove that no
such tube or opening exists. But I think that fact taken in con-
nexion with the others, especially that of the spermatic filaments
being found in various stages of development in the pouches, is tole-
rable evidence in support of the idea that the organ containing the
spermatozoa is the one which generated them. And until we hear
some more conclusive arguments on the opposite side, we may con-
sider ourselves justified in regarding the spermatheca as testicles,
and calling the entozoon a true hermaphrodite.

In conclusion, I have a word to add regarding the habits of the
entozoon I have been describing. I found two of them with their
heads projecting through the air-sac of the Cobra, and firmly fixed
by their prehensile booklets to a large blood-vessel ; from which I
conclude that they feed directly upon the blood of the animal they
inhabit. They appear to be blood-suckers in the strictest sense of
the word. In order to get to the blood-vessels to which they anchor
themselves by their hooks, the worm has to pierce the surrounding
tissues, and the hooks are no doubt made retractile into the de-
pression in order to enable the animal agaiu to withdraw its head
after it has finished its meal.

I found in the collection of Dr. Sharpey a fine specimen of an
entozoon closely resembling the one I have been speaking of
(PI. XLVI. fig. 3) ; the only difference being that it is shorter and
thicker, has only nineteen strong projecting rings instead of twenty-
seven, and that its tail is conical and not cleft ; farther, that the
vagina is about a line in front of the anus. Unfortunately no history
is attached to this specimen.

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DESCRIPTION OF ANNULOSA, PLATES XLVI. AND XLVII.

Plate XLVI.

Fig. 1 . The entozoon ; natural size.

a. The head ; the under surface showing the mouth and four prehen-

sile hooklets (two on either side of the buccal aperture).

b. The caudal extremity, showing the cleft across it.

c. The projecting rings.

Fig. 2. Small entozoon found in the nasal fossa of the Cobra ; natural size.
Fig. 3. Large entozoon found in Dr. Sharpey's collection.

a. Head, with the mouth and four hooklets.

b. The conical caudal extremity,

c. The entrance to the vagina.

d. The anal aperture.

Fig. 4. Entozoon, fig. 1, dissected. Opened on the dorsum a little to the left of
the mesial line.

a. a. The digestive canal.

b. The oesophageal ganglion.

c. The great nerve cords.

d. The vagina.

e. e. The uterus or oviduct.

The copulatory pouches or testicles (.').

g, g. The ovary.

h. The fallopian tubes.
Fig. 5. Portion of the ovary.

a, a. The ova, resembling bunches of grapes.

b, b. The homogeneous membrane loosely covering the ova.
Fig. 6. A bunch of ova highly magnified.

a. The yelk-sac, consisting of a double wall.

b. The granular yelk.

c. Germinal vesicle : indicated by the light-coloured space.

d. Germinal spot.

Fig. 7. Impregnated ovum from the upper portion of the uterus.

Pi-ate XLVII.

Fig. 8. Spermatozoa found in the copulatory pouches or testicles (?).
a, a. Granular cells.

*. The imperfectly developed spermatic filaments amassed together in
large bundles.

c. Fully formed spermatozoa.
Fig. 9. Ovum taken from the uterus 6 inches below its upper attachment.

a. The granular yelk becoming condensed and retracted from the yelk-
sac.

Fig. 10. View of ovum in a more advanced stage of development.
Fjg. 11. Profile view of a fully developed ovum. Two sets of hooklets are here
shown.

Fig. 12. Face-view of the same, in order to show the arrangement of the four

P?'''^ hooklets, and general form of the animal.
Fig. 13. Striated muscular fibres from the parietes of the parent entozoon.
tig. 14. Magnified view of a small portion of the uterus, to sliew its double layer

of non-striated muscular fibres.

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