38
85 μ. long and 50 μ. broad. A remarkable feature in these Syngames is the permanence of
copulation, which is so intimate that the males cannot be separated from the females without
tearing their integuments.''
Méguin states that " in fowls which have succumbed to this affection, the Syngames are
found throughout the trachea—chiefly near its division into bronchii, sometimes at their origin;
they are enveloped in foaming mucus. The majority of the parasites adhere firmly to the
buccal capsule that they will allow themselves to be torn rather than relax their hold; the
point to which they are fixed is often formed into a small tumour full of caseous pus.
This abscess may become so developed as to obstruct the trachea, and one alone may
induce asphyxia. The number of couples found in one bird is variable; but two or three
may kill a pheasant of four to six weeks old, though it requires twenty-five to thirty to
asphyxiate an adult Pheasant. Independently of the- power of resistance conferred by age,
the differences in other respects may be related to the diameter of the trachea."
Syngamosis generally attacks young birds, especially during certain years, and the
fattest and best conditioned may be the first to be attacked.
The ova of the syngamus trachealis are developed to a variable degree in the uterus of the
female, according to its age and size; when it is 20 mm. to 22 mm. long, the embryo is
completely formed (Cobbold, Méguin). These ova are not laid, and they can only escape from
the body of the female in case of rupture, which, in ordinary circumstances, results from
cadaveric decomposition. The ova, whether embryonated or not, fall on damp ground or in
pools of water, and are hatched in from 7 to 40 days according to the temperature. Ehlers
has shown that the embryo has no need of an intermediate host, in order to become trans-
formed into an adult worm. In birds, which he had caused to ingest ova containing embryos,
in about twelve days he found coupled individuals, and, after seventeen days, females full of
eggs. Walker has observed that the embryos remain alive in the digestive canal of the earth
worms, and that when birds swallow these, they become affected with syngamosis. Méguin
has given the ' gapes' to a parrot, by feeding it with certain number of syngames collected
from pheasants. It has been noted that affected birds often cough up the parasites, and their
companions immediately swallow them with avidity. This is evidently the way syngamosis
is propagated (Neumann).
2. Syngamus bronchialis (Mühlig).—Body cylindrical and tapering slightly in front.
Mouth arranged as in S. trachealis. Male 10 mm. long; candal pouch spherical, entire and
sustained by ribs, the two posterior of which are tridigitated, and arise from a common trunk
that is nearly double their length, the middle and anterior ones cleft, the external anterior
lying alongside the middle one; spiculæ filiform, curved at the end, and fringed at the inner
margin. Female 25 mm. long, the posterior extremity terminating in a conical point; vulva
slightly salient, and situated at the first third of the length of the body. Ova ellipsoid,
non-operculated, and 90 μ. long by 60 μ. broad. Copulation is not constant, and the coupled
worms may be disengaged without tearing the integuments.
This worm has been found by Mühlig in some young Japanese geese. The same investi-
gator met with this Syngamus to the number of 20 to 30 forming bundles in the larynx
trachea and bronchi, the ultimate ramifications of which they had reached, and where they
were enveloped in a thick mucus. There was sometimes a croupal pneumonia, and an exudate
of the same character was thrown out into the air-sacs, which also contained ova that had
undergone segmentation to a variable degree and free embryos.
The animal, hill breed, arrived at the Laboratory on 8th February 1898, having traversed
some fifty miles by short stages. It was born and reared in the villages lying midway
between the Outer-Himalayas and the snow mountains. The animals breathing became
slightly oppressed after its arrival at Muktesar, and the appetite fell off. Although suitable
food was given to it, the animal succumbed during the night of the 13th and 14th of Febru-
ary. At this time the weather was cold and several feet of snow lay on the ground.
Autopsy.-February 14th. Body weight 217 lbs. All the internal organs presented a
healthy appearance. On examination the larynx was found to contain a colony of dark red
worms ten to twelve in number, grouped together just anterior to the right—arytenoid
cartilage. Several of the parasites were detached with difficulty from the lining membrane,
to which they were fixed by their buccal cups. On section the trachea presented a healthy
appearance. The bronchi were opened up in their whole length, but no further Syngami were
discovered, and the tissues and air cells were free from any pathological change. Five couples
of Syngami were examined and their measurements recorded. Permanence of copulation was
however found in all the specimens obtained at the autopsy, and it proved to be of so
intimate a character as to render it impossible to separate the sexes without rupture of the
tissues.
The only illustration of the Syngamus trachealis which I have been able to obtain is that
of Railliet in his work on Zöologie Médicals, etc.
The minute details of the organism figured in this paper vary so much from the illustra-
tion above-mentioned that it would appear as if the Indian Syngamus must differ considerably
from the species met with in Europe—