Batrachia. 125 
at any rate 011 the posterior regions, are scattered over the whole of the dorsal sur- 
face except on the head, and the backs of the thighs are marbled The ventral sur- 
face is usually immaculate, but sometimes there is a large black spot on either side 
of the chest just in front of the fore limbs and the throat of the adult (especially 
in the male) is often slightly clouded with black. 
The head and body of full-grown frogs are together about 120 to 135 mm. long, 
about 4 of the total length being occupied by the head. 
The larva of R. tigrina has been referred to by Ferguson but has not as yet been 
adequately described, the tadpole assigned to the species by Flower being really that 
of R. rugulosa. The body is oval, about i| times as long as broad, about f as long 
as the tail, and distinctly depressed, both the dorsal and ventral surfaces being some- 
what flattened. The eye is dorsal in position, small and by no means prominent. It 
is situated at about f the distance between the base of the hind limb and the tip of 
the snout. The nostrils are situated close together on the dorsal surface, a little 
nearer the eyes than the tip of the snout. The mouth is subterminal; its disc 
closely resembles that of R. rugulosa, the dental formula being i : 4-1-4/3-1-3 : i or 
I '■ 3 + 3/,3 + 3 '• I- Both parts of the beak are very stout and of a dense black colour. 
The upper mandible bears a strongly pointed projection in the middle, which fits 
into an excavation between two similar projections on the lower mandible. There is 
a heartshaped horny pad on the roof of the mouth and a conical projection tipped 
with horn at the base of the lower jaw inside the mouth on each side. The tail is 
narrowly and regularly lanceolate, the upper and lower profile being almost sym- 
metrical. The upper membrane does not extend forwards on the body. The coloura- 
tion of the tadpole is never conspicuous but varies considerably in different surround- 
ings. The back is darker than the sides and usually bears a Y-shaped dark mark, 
the divergent lines extending backwards from the eyes. There is also a small black 
spot or crescent behind each nostril. The ventral surface is whitish, somewhat iri- 
descent on its posterior half. The tail is speckled greyish. The size varies greatly 
in correlation with nutrition, etc. 
Geographical Distribution. — The true R. tigrina, originally described from Bengal, 
occurs all over the plains of India proper, Assam, Lower Burma and Ceylon. In 
Upper Burma it is apparently rare, but specimens are found as far east as the 
Chinese province of Yunnan. On the eastern side of the Bay of Bengal I have seen 
no specimens from further south than Tavoy. The species avoids hilly country. 
It is essentially a pond frog but in districts where there is a distinct dry season 
aestivates or hibernates in holes in the ground. The tadpole is found in pools and 
ponds. 
The following is a list of the adult specimens in the Indian Museum : — 
9227 . . . . vSind . . . . . . Karachi Mus. (Ex.). 
9041 . . . . Rajanpur . . . . . . C. vSanders. 
9025 .. .. Agra, U.P. . . .. .. Agra Mus. (Ex.). 
15866-69 . . . . vSuudrijal and Katmandu, Nepal . . R. A. Hodgart. 
16457 . . . . .Sukna, base of E. Himalayas . . Mus. CoUr. 
