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Show 32 ZOOLOGY OF TilE VOYAGE OF TilE BEAGLE. RANA MASCARIENSIS. PLATE XVI.-Fig. 2. Dentibus palatinis in fasciculis binis obliquis distantibus, ad marginem inte1·iorem narium posteriorum attingentibus; tympano circulari, mediocri; digitis posticis usque ad phalanges penultimas connexis : plantis tuberculo unico ; cute dm·si lcevi, longitudinaliter plicata ,· suprafusco-rufescens,fascia longitudinali pallida. Rana ltfascariensis, Bibr. Ilist. Rept. VIII. p. 315. Habitat, the Mauritius. This pretty species of the typical genus of the family was described by Bibron, but has not hitherto been figured. It was found in Mauritius, on swamps near the sea, by Mr. Darwin, who remarks on the extraordinary height of its leaps. It has also been found in the Seychelles, Madagascar, and the Island of Bourbon. GENus-LIMNOCHARIS. Bell. Lingua ovalis, integra, margine posteriore libero. Dentes palatini utrinque in fasciculis duobus dispositis, quorum alter ad marginem anteriorem narium interim·um, alter pone nares interiores, p1'0pe arcum maxillarem Nasus terminalis, t1·uncatus, ultra labium productus. Tympanum conspicuum, circula1·e. Cutis omnino lcevis. Digiti anteriores liberi, posteriores ad basin tantum palmati. The genus Limnoclta1·is is remarkable for the existence of palatine teeth in a part of the mouth in which they have never been observed in any other amphibian. Not only is there a small group or line of these contiguous with the anterior margin of the posterior nares,-a situation in which they are found in some other genera of Ranidce, but there is also a group of them placed at some distance behind the posterior margin of these openings, and close within the rise of the maxillary arch. This genus, of which one species only is at present known, will probably be most naturally placed between the true Rance and certain of the Cystignat!ti. REPTILES. 33 LaiNOCHARis Fuscus. Milti. PLATE XVI.-Fig. 3. Habitat, Rio Janeiro. DESCRIPTION.-f!ead se~i-~val, depressed, as broad as it is long. The muzzle truncated, extending ~cyond the .lips, whiCh 1t overhangs. Tongue oval, entire, free at the posterior margin. Palatme .teeth 10 two pa~cels on each side; one consisting of very few at the anterior and inner mar~m of the postenor narcs, the other behind those openings, in the angle formed by the maxilla? arch and. the orbits. Posterior nares large and oval. Tympanum conspicuous, nearly Circular. Skin every where perfectly smooth, without glands or pores. Anterior legs of moderate length and size. The fore-arm rather longer than the upper arm. Fingers of moderate length, wholly ~etachc~. IIin~cr legs little more than one-third longer than body. The toes separate, exceptmg a shght rud1ment of a connecting membrane at their base, which extends, though very narrow, along their sides, the extremity very slightly notched. CoLOUR of the upper part rich dark brown. The thighs lighter, obscurely banded with dark brown. Under parts pale blueish grey. The throat dotted with brown. DIMENSIONS. In. Lin. Length Of the head aud body........... .. ..... 4 of tho anterior extremities............ 7 of the posterior extremities .... .. .. . Found in brooks at Rio Janeiro by Mr. Darwin, who states that it is infested with acari; and I observe, in the specimen under examination, several marks in the skin, from whence these have been taken. GENUs-CYSTIGNATHUS. Wagler. CYSTIGNATHUS GEORGIANUS. Bibr. PLATE XVI.-Fig. 4. Dentibus palatinis perpaucis, i1t fasciculis binis approximatis, pone nares posteriores ,· lingutJ. integrd, ohlongd; tympano celato ; pedibus posteriorihus non palmatis. Orinia Georgiana, Tschudi Class. Batrach. OJ!stignathus Georgianus, Bibr. Rept. VIII. p. 416. This species, which formed the type of Tschudi's genus Crinia, was separated by him from Cystignat!tus on account of the form of the tongue, the nonF |