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Show 1899.] BATRACHIANS OF THE MALAY PENINSULA AND SIAM 909 Size. The largest specimen from Penang measured, snout to vent, 37 m m . Distribution. Malay Peninsula, Borneo. Tadpole. Tadpoles aud newly transformed young toads were found in abundance in two streams on Penang Hill, at elevations of about 1800 feet, during March 1898. Habits. These tadpoles live in the swift-flowing hill-streams, and are to be found where the torrent is rushing fastest, fixed to the face of the granite boulders which obstruct the stream; a favourite place of theirs was a perpendicular wall of rock which the water fell over in a small cascade ; they hold on so fast with their mouths that they cannot easily be pulled off, but have to be plucked away from the rock between one's finger aud thumb. They move upstream and about the face of the rock by means of their mouths; when placed in a glass bowl they never laid on the bottom (as most tadpoles do), and seldom swam about but fixed themselves to the glass sides. In captivity they died in a few hours, the still water probably not suiting them. Description of the Tadpole (in the 3rd period). Form. Length of body from rather more than once and a half to rather less than once and two thirds its width, nearly half the length of the tail. Nostrils much nearer the eyes than the end of the snout, about a quarter the distance. Eyes on the sides of the head, looking outwards and upwards, not at all prominent in life ; the distance between the eyes is rather more than once aud a half as great as that between the nostrils, and little more than half as great as the width of the mouth. A strongly marked lachrymal canal from in front of the eye to the nostril. Spiraculum on the left side, directed back./ards and upwards, rather nearer t»he eye than the anus, not at all prominent in life. Anus median. Tail six times as long as deep, acutely pointed; upper crest only on posterior two-thirds of tail, lower crest whole length of tail, but only the posterior two-thirds are pigmented ; crests of equal depth or lower slightly deeper. Mouth. The large mouth forms an organ for adhesion and locomotion. Beak white ; lower jaw edged with black, upper with a conspicuous black diagonal mark on each side. The lips form the rim of a sucking-disk, when not fully expanded they take a crenular form (in spirit-specimens this is very marked) ; the upper lip, which has its edge turned in and terminating in the 1st row of upper labial teeth, is smooth and free from papillae; the enlarged muscular lower lip is thickly studded with very small short rounded papillae. There are two uninterrupted series of upper labial teeth of equal length, the 2nd being slightly stronger than the 1st: three uninterrupted series of lower labial teeth of equal length but shorter than the upper series ; the 3rd is the strongest and the 1st the weakest. PROC. ZOOL Soc-1899, No. LIX. 59 |