H. D.
SRIVASTAVA
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0.12. Usually it lies in the median line, about the middle of the body length.
The small oviduct receives a duct from the receptaculum seminis just before
entering the shell gland mass, which is situated between the ovary and the
right body wall. A small Laurer's canal is given off by the receptaculum
seminis just before opening into the oviduct. The yolk reservoir opens into
the oviduct just before the opening of the receptaculum seminis. The vitel-
laria are composed of ten elongated, spindle-shaped lobes, extending in
equal numbers both in front and behind the testis. All the lobes join
together halfway between the testis and right body wall, at about the level of
the anterior third of testis. In front of the testis, the lobes extend up to the
anterior margin of the receptaculum seminis and posteriorly to the last third
of the post-testicular space. In contracted specimens the vitelline lobes
extend anteriorly up to the middle or anterior third of body length, and pos-
teriorly almost to the hinder end. The uterus is short, pre-ovarian and con-
tains a moderate number of ovoid, light brown, thin-shelled eggs of 0.05 to
0.07 by 0.038 to 0.05 size. The terminal part of the ductus hermaphroditicus
is protrusible.
The excretory bladder is Y-shaped. The main stem bifurcates into two
fairly long cornua at the hinder end of testis. The excretory pore is sub-
terminal and is guarded by a feebly muscular sphincter.
Waretrema piscicola Gen. et. sp. nov. resembles the papillose Allo¬
creadiidae in having a crown of six papillae dorsal to the oral sucker, in the
pre-ovarian character of the uterus and in the position of the genital pore in
front of the acetabulum. However, it differs remarkably from the latter
group of parasites in the length of oesophagus and caeca, presence of a single
testis and of a peculiar structure termed as hermaphroditic sac, the character
and position of vitellaria, besides the Y-shaped character of the excretory
bladder. The new genus resembles the members of the family Haploporidae
Nicoll, 1914, Dicrogaster, Haploporus, Saccocoelium and Lecithobotrys [Looss,
1902]—in its digestive system, number of testis, the shape of the excretory
bladder and somewhat in the character of the terminal genital ducts. Never-
theless, it can be readily distinguished from the members of the latter family
by the presence of a crown of six papillae dorsal to the anterior half of the
oral sucker, shape and character of the hermaphroditic sac, character and
position of vitellaria, pre-ovarian configuration of the uterus, topography of
the gonads and the absence of miracidia with prominent eye-spots in the eggs.
Linton [1910] created the genera Megasolena and Hapladena but did not
indicate their family connections. Recently Manter [1935] studied the struc-
ture and taxonomic position of Megasolena and has pointed out the am-
phistome affinities of both these genera. He assigns them to a new sub-
family Megasoleninae under the family Opistholebetidae Fukui [1929]. In
possessing a hermaphroditic sac Waretrema resembles Brumptia, Megasolena
and Hapladena but it differs markedly from them in all its other characters.
Thus it is evident that the parasite described in this paper is unique amongst
the families of digenetic trematodes and, therefore, it is considered necessary
to create a new genus and family for its reception.