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Show 1891.] TADPOLES O F T H E E U R O P E A N BATRACHIANS. 615 fifth as long as deep, acutely pointed; upper crest convex, deeper than the lower, not extending far upon the back ; the depth of the muscular portion, at its base, about half the greatest total depth. Beak black. Lip bordered with papillae, which form two or more rows on the sides ; the papillose border interrupted mesially by a narrow toothed descending lobe, which appears at first sight as continuous with the second upper series of teeth *; this anterior series is followed by three or four other series of teeth, which are all widely interrupted in the middle and gradually decrease in length ; the fourth, if at all present, being extremely short. On the lower lip we see likewise a short outer series, followed by three or four much longer ones, all of which, with the occasional exception of the first, are interrupted in the middle and may be more or less broken up on the sides. The series of labial teeth may therefore be formulated as -. or -=. Small isolated teeth may also be scattered on the papillae at the angles of the mouth. I have not been able to distinguish lines of crypts beyond the two series which run from the end of the snout to the upper border of the eyes, passing between the nostrils. I am therefore unable to judge whether the dorsal lines have been correctly figured by Lessona (Atti Ace. Lincei, 3, i. 1877, pi. v. figs. 20 & 28), who rightly regards the figure given by Cornalia (Atti Soc. Ital. xvi. 1873, pi. iii. a.) as fanciful. From what I know of other tadpoles, I can hardly believe in the arrangement described by Lessona, especially as so great a difference from the allied P. eultripes, figured by Lataste (Actes Soc. Linn. Bord. xxxiii. 1879, p. 313), appears very improbable. The advanced tadpole of P. fuscus is brown or olive-brown above, with or without small darker spots, greyish white beneath; sides with roundish whitish or pale golden spots ; tail pale brown, with small grey and whitish spots. The body usually reaches at least the size of a pigeon's egg, but not unfrequently exceeds that size. The largest specimen in the British Museum, from Prague, measures 125 millim.: body 38, width of body 25 ; tail 87, depth of tail 27. The largest specimen 1 And is so figured by Heron Royer and V a n Bambeke (Arch, de Biol. ix. 1889, pi. xix. fig. 1) as characteristic of P. fuscus, such as it occurs in France. But specimens from Paris, which I received from M . Heron Royer himself, show exactly the same arrangement as described and figured (I. c. pi. xviii. fig. 7) in Pelobates from Belgium, Germany, and Italy. Had the difference been a real one, M . Heron Royer might have reflected on m y remarks (Bull. Soc. Zool. France 1888, p. 115) to the effect that if there exist two distinct forms confounded under the name of P. fuscus, it is the French form that is to be distinguished and not the Italian, which agrees best with the typical P. fuscus of Germany. On reading Heron Royer and Van Bambeke's account, one might feel inclined, on the evidence of the differences shown by their figures, to accept such a distinction; but, considering that the Parisian tadpoles do not in any way differ in their labial characters from the German, as figured by F. E. Schulze and Gutzeit, nor from the specimens from Prague, Basle, and Denmark with which I have compared them, I feel justified in regarding Heron Royer's figure (I. c pi. xix. fig. 1) as incorrect. |