Batagur a by the presence of two strong palatal ridges, the inner, however, being
much smaller than the outer ridge.
The female referred by Theobald to B. trimttata had no trace of black bands
on the shell, which, instead of being greenish above, as in the male, and yellow below,
was uniform brown, above and below. Now, in Batagur duvaucelU, which is a very
nearly allied form, and the sexes of which are well known, and which has its
shell with three black dorsal streaks, as in the males referred by Theobald to
B. trimttata, there is no such difference in the colour of the shells of the two sexes,
which are both black-streaked. There is this to be said, however, that these males
referable to the species B. trimttata differ from the males of B. duvaucelli in
attaining to a much greater size; the males of B. duvaucelU, as far as my observations
go, seldom exceeding 9 inches in length, whilst some females are 16 inches
long; the largest male, B. trimttata, from the Irawady attained to 17"-90. Besides
these differences in size subsisting between the sexes of B. duvaucelli, there
can be no doubt hut that among some species, at least of Batagur, the male, as
in birds, is a much more brilliantly coloured animal than the female, if not at all
times, at least during the breeding season. This is the case in the species known as
B, limeata, in which the head and neck of the male are brilliantly coloured, black,
scarlet and yellow, and it also holds good in B. baska, in which the male has the area
around the nostrils waxy-blue, the anterior portion of the head, behind this, deep
black, followed by brilliant scarlet, extending over the neck even to the fore limbs.
The male of B, lineata is a small animal compared with the female, but in
B. bastea there is no great disproportion between the sexes. In another sub-genus,
(Bardella) there does not appear, as far as my experience goes, to be any difference
in colour between the males and females of this very common river tortoise B. (Bar-
della) thwgi, but the largest female of it which I have measured was 19"'10 compared
to 6'-20, the length of an adult male; and a proportion between the sexes
somewhat similar to this prevails among the so-called Bamgshwes, and a great disproportion
also occurs between the sexes of the sub-genus Morenia, all of these
forms presenting more or less one type of structure. In the Bangshures, in which
the males are small, the lineation of the shell, if it occurs in one sex, is always present
in the other, and in Bardella the shells of both sexes aré more or less lineated,
and, in Morenia, the shells of the males and females are alike ooellated. There are,
however, such great differences between the colours of the soft parts of the sexes in
such species as B. Imeata, in which the head and neck are brilliantly streaked red and
black, these parts in the female being dull olive, that the difference of colour subsisting
between the males and females referred by Theobald to B. trimttata, even in
view of the conformity of colouring in the male and female of B. duvaucelU and the
other forms mentioned, should not have deterred me in unreservedly accepting
Mr. Theobald’s conclusion regarding the specific identity of these males and females
had there been a strong similarity in the form of the shells, and had I not received
from the Irawady a young male tortoise (PI, lxiv), resembling the females in
question, and to that degree that it may ultimately prove to be the male of the
females referred to B. trimttata by Theobald, because its shell much more resembles
the shells of the females than the shells of the black-striped males. Moreover,
although a little younger than the male (PI. lxii), its characters are such that
it seems highly improbable that it could ever attain to the characters presented by
that species, and which is unquestionably B. trimttata, D. and B. Besides, I have
obtained from the Irawady young females nearly of the size as this young male, and
agreeing with it in every particular of shell form. These young females correspond
in all essential particulars to the adult females considered by Theobald to he females
of B. trimttata. As the yoiing brown,male cannot be reconciled as specifically
identical with the black-banded males; and as moreover it does not exhibit any
capacity whatever, ever to change by growth into the form and colour of the
males of undoubted B. trimttata, it would appear that there are two species of
Batagur in the Irawady closely allied by the characters of their vertebral plates
and skulls, but differing from each other in the general form of their shells and
in their coloration; the females of B. trimttata, according to this view, being
unknown, whilst both sexes of the other are known, the females constituting in
part the species first described by Dr. Gray under the name of B. fusca. This latter
term, however, is open to objection, as Dr. Gray included in it two species; therefore,
I propose to distinguish the species represented by these females and young
male as JB. iravadica.
However, I separate these tortoises specifically with some hesitation, because the
skulls of the adult males and females referred by Theobald to B. trimttata are so
alike to one another, and so resembled by the skull even of the uniformly coloured
male, that I cannot seize on any cranial character which would separate them
, specifically, unless it be the greater upturning of the nasals in the latter. Looking,
however, at the young male (PI. lxiv) as a whole, and comparing it with
the young male of B. trivittata, (PI. lxii), the external features are very different
efe., the shorter and relatively higher shell of the former, the inward projection
of the second costal between the second and third vertebráis, the more serrated jaws,
as in the female (PI. Ixviii), and the uniformly brown shell compared with the
green thrice black-banded shell of B. trimttata. The short rounded head and the
spinous nodosities of the vertebráis are youthful characters.
The shell of an adult male of B. trimttata, the sex of which was accurately
determined by me, presents the following characters
The shell is oval, somewhat expanded posteriorly, with slightly reverted marginals.
I t is highly and roundedly arched anteriorly, and therefore deep, but the
posterior half of the shell is somewhat depressed. The young male, however, figured
(Pis. lxii and lxiii) is not so.highly arched over the first and second vertebráis; and
the dorsal ridge, which is absent in the adult, is strongly marked. The plastron has
the general form in the genus, and in the adult is devoid of the lateral ridge which
exists in the young. In the full-grown male, the nuchal is large, triangular, broad
posteriorly and narrow anteriorly, which is its general form. The first and second
vertebráis are of equal breadth, with their lateral margins slightly sinuous, the shields