16
INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY
[VOL. XXIX, PART I
somewhat conical in shape with the pointed anterior end provided with prominent papillae,
particularly around the margin of the mouth. The ventral surface is somewhat flattened
while the dorsal is convex.
Oral sucker is terminal and measures 0.7 × 0.5 mm. in size with two characteristic
diverticulae or pouches (pharyngeal sacs). The oesophagus, 1.04—1.2 mm. in length,
is posteriorly enlarged into a well developed muscular swelling before bifurcation into
intestinal caeca which are wavy and reach posteriorly to the level of the anterior margin
of the acetabulum. The acetabulum is sub-terminal and 1.2 —1.3 mm. in diameter.
The common genital pore leading into a genital atrium in the form of a well developed
and faintly muscular genital cone lies behind the intestinal bifurcation. The testes are
much branched, situated directly one behind the other, and are near the middle of the body.
The anterior one is 0.4—0.8 × 1.0—1.2 mm. in size while the posterior one is 0.4—0.9
× 1.0—1.22 mm. in size. A prominent vas deferens arises from each and the two ducts
pass forward to open into an enlarged and slightly coiled seminal vesicle lying in and behind
the zone of the genital cone. The ovary is post testicular, preacetabular, of rounded outline
and 0.3—0.4 × 0.5—0.6 mm. in size and lies in the median plane and in front of the
posterior level of the caeca with Mehlis gland on its lateral aspect. The first coils of uterus
are in line with ovary and Mehlis gland and then pursue a course with the coils in front
of the anterior testis being prominent before opening into the female genital pore. Vitellaria
are mainly laterally extending from near the intestinal bifurcation to the level of the anterior
margin of acetabulum. Eggs were not encountered in the uterus.
Bhalerao, in his description of the specimen collected from Madras, has added to the
account of Stiles and Goldberger. The stained preparation and the sections studied by
us from our material and those received from Indian Veterinary Research Institute for
comparison clearly indicate that the genital pore in our specimens is behind the intestinal
bifurcation as given by the joint authors, but the testes in all our specimens are directly
one behind the other. This genus, according to Bhalerao, has both the species P. collinsi
and P. hawkesii. Skrajabin has, on the other hand, separated P. hawkesii and included
it under the genus Hawkesius [Stiles and Goldberger, 1910] and placed this under the sub-
family Watsoniinae of Nasmark. P. collinsi differs from P. hawkesii in the position of the
testes, which in the former lie symmetrically one on each side while in the latter the testes
are one behind the other We feel that the genus Pseudodiscus with both the species,
P. collinsi and P. hawkesii, would come under the same sub-family Pseudodiscinae of the
family Cladorchidae. The character of the position of the two testes can be well utilised in
identifying the two species of Pseudodiscinae.
SUMMARY
Three species of amphistomes, collected from an Indian elephant, have been studied
and assigned to the species Pfenderius papillatus [Cobbold, 1882; Stiles and Goldberger,
1910], Pfenderius heterocaeca [Fukui, 1926 ; Bhalerao, 1935] and Pseudodiscus hawkesii [Cobbold,
1875; Stiles and Goldberger, 1910]. Previous literature on amphistomes from Indian
elephant has been reviewed and omissions observed in earlier descriptions and diagrams
have been pointed, after giving brief accounts of the three species. A key to the known
species of Pfenderius has been given and the taxonomic position of Pfenderius and Pseudodiscus
among amphistomes indicated.
ACKNOWLEDGEMENT
The authors are grateful to Dr. B. P. Pande, for his supervision, guidance and going
through the manuscript. They also thank Shri C. V. G. Choudhary, Principal, for providing
the facilities, to Dr. H. D. Srivastava, Head of the Division of Parasitology, Indian Veteri-
nary Research Institute, Izatnagar for the loan of some slides from his collection as also
for some literature and Shri J. S. Srivastava for the help in the collection work.