HELMINTH PARASITES OF THE INDIAN ELEPHANT,
41
[1932], but this author had only one pair of worms at his disposal and therefore the
description is not complete. The present opportunity is therefore taken to revise
in more detail the description of the worm from the study of a number of specimens
available to me.
Description. The spirit preserved specimens are red in colour. A few of the
worms were in copula but a large majority of them were separate. The males have
their body gradually increasing in thickness posteriorly with a constriction imme-
diately in front of the bursa. The body of the female grows thicker to a distance
more than half its body length, then it gradually diminishes in thickness posteriorly.
The cuticular striations are very indistinct. The cervical papillæ are short and thick
being at the same level as the nerve ring or slightly posterior to it. The excretory
pore is either slightly anterior to the nerve ring or level with it. A definite mouth
collar is absent. The mouth opening is terminal and is surrounded by two lateral
and four sub median papillæ. The buccal capsule is more or less subglobular in
appearance and is supported internally by six ridges which arise from its anterior
border and correspond with the papillæ, so that the number of ridges is
also two lateral and four submedian. The two shorter ribs described for Syngamus
laryngeus by Ware [1925] and for S. hyppopotami by Gedoelst [1924] are not present
in this species. At the base of the buccal capsule there are eight salient teeth and all
these, excepting the dorsal and the ventral ones, stand against the ridges.
Male.—The males measure 3.75—6.5 in length and the maximum thickness
which is attained at about the posterior third of the body is 0.31—0.44. The
cuticular striations are 0.014 apart. The cervical papillæ are situated at a distance
of 0.675—1.110 from the anterior end. The excretory pore is at a distance of
0.575—1.07 and the nerve ring at a distance of 0.66—0.76 from the anterior
extremity. The breadth of the nerve ring is 0.125—0.17. The buccal capsule
measures 0.235—0.32 × 0.23—0.32. The teeth are 0.1—0.127 long and 0.025—
0.028 broad at the base. The club-shaped œsophagus measures 0.9—1.2 in length
and is 1.181—0.265 in maximum thickness.
The bursa is very short but well developed. It measures 0.28—0.43 × 0.125—
0.18.
While the worms are in natural copula the dorsal portion of the
bursa is directed towards the anterior side of the female, while the ventral
portion is directed posteriorly. The lateral lobes embrace the sides of the vulvar
region. The prebursal papillæ are absent. The bursal formula differs in some
respects from that described by Mönnig [1932] and is as follows :—The ventral
rays are stout and short and lie close together. They end abruptly in narrow points
and look like bananas. The antero and medio-lateral rays arise from a
common trunk, lie close together, and appear together like the thumb and index
finger of man. In some cases they are seen to end in narrow points like the ventrals
The postero-laterals arise separately from the other laterals beginning in some cases
with a narrow base as described by Mönnig, but the base is not so narrow in all cases;
n some cases the base appears almost as broad as the remainder of the ray. In
none of the specimens I examined was this ray as much separated from the other