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Show 618 MR. G. A. BOULENGER ON THE [Nov. 17, upwards posteriorly, sometimes extending nearly to the origin of the hind limbs. In addition to these lines, a short horizontal branch oiiginates above the upper lip, and, bifurcating below the vertical of the anterior border of the eye, forms a hoop which descends to the sides of the throat. The arrangement of these lines is figured on p. 598 of this paper. Coloration usually varying from pale grey to olive-brown above, the sides with pale metallic spots ; the lines of crypts whitish ; caudal crests greyish, with blackish spots and white dots and pale metallic spots. Some specimens, however, have the tail almost spotless ; in others, on the contrary, it is very closely spotted, but always less abundantly on the lower crest than on the upper. Lower parts pale grey with silvery spots. Tail and the greater part of the body with fine black decussating lines, as in Bombinator; it sometimes happens that these lines are altogether absent on the muscular part of the tail. But, as in other tadpoles, coloration is subject to a great amount of variation. During a stay of seven weeks in Brittany last summer, I was much struck on finding, in the beginning of July, near St. Enogat, Ille-et-Vilaine, a small and shallow pond, about 15 feet long by 10 feet wide and 2 feet deep, swarming with thousands of tadpoles from 30 to 40 millim. long, of a very dark brown, almost black, which, although I am familiar with the larvae of Pelodytes, I at first failed to recognize. It was only after a careful examination that I ascertained the species to which they belong, m y determination being ultimately confirmed by the transformation of some of the tadpoles which I had brought home alive. Now several ponds close by, whether large or small, deep or shallow, of clear or of thick muddy water, all showed the ordinary type of Pelodytes-tndpole. I constantly visited the spot: the water, which at first was perfectly clear and transparent, became green and dirty, but the larvae did not alter in colour or size ; and I was surprised at the small size of the young immediately after transformation, which did not exceed 11 to 15 millim. from snout to vent, whilst the other places yielded young varying between 19 and 22 millim. Towards the middle of August the little pond was taken up for those linen-washing operations with which all who have visited Brittany are unpleasantly familiar, and m y observations were thus terminated by the wholesale destruction of the tadpoles. But those, still numerous, which had remained up to that time had not undergone any change. As I have said above, these tadpoles were nearly black on the back ; the tail was of a dark brown without any, or with but very small, black spots, and with the black decussating lines so crowded that they could not be detected without a lens ; the belly was of a beautiful steel-blue, and the lines of crypts were quite indistinct, although they have become distinguishable now that the specimens have been for some time in spirit. One of these black tadpoles is figured, Plate X L VII. The largest measured: body 16 millim., width of body 10; tail 24, depth of tail 8. The young were by no means melanotic, |