18 REPTILES. 



18. Rana bibronii. 

 Hallowell, Proc. Ac. Nat. Sc. Philad. 1846, p. 249. 



Head longer than broad ; muzzle rather elongate and pointed ; 

 tympanum two-thirds the width of eye ; skin of the back with nar- 

 row longitudinal folds. Legs and toes slender, half- webbed ; fourth 

 toe one-third longer than fifth ; metatarsus with one tubercle. Vo- 

 merine teeth small, in two rather oblique series, beginning from near 

 the front edge of the inner nostrils. 



A whitish longitudinal band from the snout to anus ; above with 

 dark spots ; sides of head brown ; a white band from just below the 

 eye to the shoulder ; beneath uniform whitish. 



a. Half-grown. Gaboon. From Mr. Cimiing's Collection. 



19. Rana grayi. 



Smith, Elustr. of the Zool. of 8. Afr. pi. 78. f. 2. 



Head nearly as long as broad, with moderate, rounded muzzle ; 

 tympanum circular, half the width of eye ; skin of the back and 

 sides with broad longitudinal folds, and flat tubercles between. Toes 

 rather elongate, webbed only at the base ; fourth toe one-third longer 

 than fifth ; metatarsus with one, rather prominent tubercle. Vomer- 

 ine teeth in two, rather oblique series, situated near the front edge 

 of the inner nostrils. 



Bro-miish yellow, brown variegated with large brown spots above ; 

 temple brown ; beneath straw-yellow. 



a-c. Adult and half-grown : discoloured. South Africa. 



20. Rana mascareniensis. 



Bum. Sr Bibr. p. 350 ; Bell, Zool. of the Beagle, Bqjt. p. 32. pi. 16. f. 2. 



Body with six or eight longitudinal folds ; toes and fingers slender, 

 with blunt tip and moderate subarticular tubercles ; toes not webbed 

 to the end, fourth one-third longer than fifth and third ; metatarsus 

 with one tubercle. Vomerine teeth in two obhque scries. Tympanum 

 distinct, of moderate size. Grejash or brown above, sometimes black- 

 spotted, with or without paler vertebral band. On each side of the 

 tongue a sht for the vocal sac. 



«. Adult : bad state. Isle de France. Presented by Charles Darwin, 

 Esq. 



21. Rana fuscigula. 



Dum. (.^- Bibr. p. 386 ; Smith, III. of S. Afr. Ajyp. p. 22. 



Head as long as broad ; muzzle rather short, rounded ; tympanum 

 distinct, moderate ; skin of back ^Yith irregular longitudinal plaits ; 

 toes of moderate length, webbed to the tip, but deeply notched ; fourth 



