REPTILES. 43 



Genus— BATRACHYLA. Bell. 



Lingua suborbicularis, postich libera. Dentes palatini in fasciculis binis obliquis 

 inter nares posteriores dispositi. Tympanum distinctum, parvum, rotundum. 

 Digiti depressi, ad apicem paulld dilatati, truncati. Anteriores ad basin tantum 

 — posteriores paulo plus pahnati. 



This genus, which considerably resembles Hylodes, is nevertheless suf- 

 ficiently distinct from it, in the distribution of the palatine teeth, in the form of 

 the dilatations of the toes, in the presence of a small palmar membrane, and 

 some other points. One of the most remarkable of its characters is the form of 

 the dilatation at the extremity of the toes ; it is very small, transverse, trun- 

 cated, and even a little emarginate ; in this respect it must be considered as con- 

 stituting a very near approach to the family of the RanidjE. We are unfor- 

 tunately without any information as to the habits of the only known species 

 which could throw any light upon its relations; but it is very clear that the 

 dilatations of the toes are not such as to constitute it a true tree-frog, nor, on the 

 other hand, are the connecting membranes of sufficient extent to give it the 

 typical character of the swimming group of these animals. 



Batrachyla leptopus. Mihi. 



Plate XVIII.— Fig. 5. 



Description. — Head depressed, broad, rounded. Nostrils small, placed near together. Eyes 

 large, opening considerably upwards. 1 ongue nearly round, the posterior part free for about 

 one-third of its length. Palatine teeth placed in two small oval groups, placed obliquely, 

 between the posterior nostrils, separated from each other by a considerable space. Tympanum 

 small, nearly round. Limbs of moderate length. The toes on all the feet depressed, slender, 

 the terminal dilatation very small, transverse, truncated ; those of the fore feet connected at 

 the base only, those of the hinder to the union of the first and second phalanges ; of those of 

 the fore feet the third is the longest, then the fourth, the second, and the first ; of the hinder 

 the fourth is the longest, then the third and fifth equal, then the second and the first. There 

 are some minute scattered glands on the posterior part of the thighs. 



The only specimen in Mr. Darwin's collection is in so bad a condition, that 

 it is impossible to say with any certainty what is its natural colour. It is brown 



G 2 



