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THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, I
laterals as is indicated in Mönnig's figures. The extreno-dorsal rays arise quite
independently, but are not the thinnest of all the rays as described by Mönnig. In
all the specimens examined they appeared to be stouter than the dorsal rays. The
distal end in some cases was observed to end in a narrow point, while in others it ter-
minated bluntly. The dorsal rays arise quite independently and are far apart. Their
distal end terminates in very irregular, small digitations. They appear, as remarked
by Mönnig, " broken off". Mönnig, having only one pair of worms at his disposal,
did not observe the spicules. A large number of specimens being available for study
enabled me to see these minute structures by dissecting a few males. These spicules
are like small nails and measure 0.06—0.075 in length.
Female.—The females measure 8.6—18.5 in length and the maximum thickness
which is attained in the region of the vulva is 0.335—0.64. The tail is short,
measures 0.168—0.22 in length and narrows down abruptly behind the anus. The
terminal portion of the tail is bent towards the ventral side as has been remarked
by Mönnig. The cuticular striations are 0.008—0.022 apart. The cervical
papillæ, the excretory pore and the nerve ring are situated at a distance of 0.87,
0.77—0.95 and 0.68—0.8 respectively from the anterior extremity. The nerve
ring is 0.145—0.16 broad. The buccal capsule measures 0.31—0.4 × 0.25—0.35.
The teeth measure 0.083—0.118 in length and are 0.023—0.029 broad at the base.
The oesophagus is 1.07—1.78 long and its maximum thickness is 0.22—0.33.
The vulva is situated at a distance of 4.4—5.8 from the anterior extremity. It has
been observed that in younger specimens the proportion between the part of the
body anterior and posterior to the vulva is greater than is the case in well developed
specimens : thus in the youngest specimen studied the proportion between the
pre-vulval and post-vulval regions is 1 : 2, while in the largest specimen studied it
is 1 : 3. Mönnig remarks " The vagina is very short and gives rise to two thin
walled tubes which both run forwards but soon turn and widen to form the two
uteri". My observations do not exactly conform to those of Mönnig. The vagina
is short, and soon bifurcates and forms the two uteri. These latter have different
dispositions in gravid and younger specimens. In the latter case the uteri pass
directly towards the portion of the body posterior to the vulva, while in the former
case the uteri describe a short loop anterior to the vulva before turning posteriorly.
In the gravid females the genitalia occupy a little less than three-fourth of the post-
vulval region of the body, but in the younger forms they occupy nearly half the post-
vulval body portion. Mönnig remarks that'' each ovary has one short loop lying
anterior to the level of the vulva ". This was not found to be the case in any one
of the specimens I examined. None of ovarian coils were seen even in the region
of the uteri, which are found much posterior to the vulva. All the ovarian coils are
confined to the post-uterine region. Between the dense coils of the ovary and the
uteri the winding oviduct can be distinguished. The eggs measure 0.088—0.092
× 0.046—0.0475 and their shell is thickened at the poles. The segmentation
starts in the uterus, but in none of the uterine eggs were seen more than two
segments.