2. RAXA. 9 



and T therefore do not hesitate to unite Hoplohatrachus ceylanicus 

 "vnth Sana tigrhui. 



The common Rana esculenta furnishes a similar example in favour 

 of this view. In this species the inner metatarsal tubercle is liable 

 to considerable variation. Some specimens, especially those from 

 8. Europe, jS". Africa, and W. Asia, exhibit it blunt, small, one third 

 the length of the first toe ; most of those from j^orthern and Central 

 Europe have it compressed, about half as long as the first toe ; 

 most of the Chinese and Japanese specimens have it still stronger, 

 very frequently quite as long as the first toe, and closely resembling 

 the spur of Pelobates. I may add that I am inclined to consider 

 Hojplohatraclms reinhardti, Peters, as based upon one of these oriental 

 specimens of R. esculenta ; and that I saw some time ago in the 

 Paris Museum a large specimen of the same species labelled Hoplo- 

 batracJius davidi, sp. n. 



On the other hand, in some species of Pyccicephalus, viz. P. nata- 

 Icnsis and P. rugosus, the metatarsal tubercle is not more developed 

 than in that form of R. escidenta which is intermediate between 

 the extremes. 



As regards the stouter habit and the thicker head of Pyxicephalus 

 as compared with Rana, we must bear in mind that the latter genus 

 includes some very stout species, and that P. nataleusis has the head 

 very much like the majority of the species of Rana. 



Synopsis of the Species. 

 I. P.AL^AECTic Species. 



A. Tips of fingers and toes not dilated ; belly smooth. 



1. Vomerine teeth between the choanse ; a glandular lateral 



fold ; toes entirely webbed. 



Fingers pointed ; glandular lateral fold as 

 broad as the upper eyelid ; a dark band 

 along the hinder side of the thighs .... 88. plancyi, p. 37. 



Fingers blunt ; glandular lateral fold nar- 

 rower than the upper eyehd ; hinder side 

 of thighs marbled 39. esndenta, p. 88. 



Upper eyelid glandular and distinctly porous 40. porosa, p. 40. 



2. Vomerine teeth between the choanae ; no glandular lateral 



fold ; toes incompletely webbed. 

 Skin very warty 88. rugosa, p. 85. 



3. Vomerine teeth extending beyond the level of the hinder 



edge of the choanae ; a glandular lateral fold : toes in- 

 comi^letely webbed ; a dark temporal spot. 



a. Tibio-tarsal articulation not or hardly reaching the tip 

 of the snout. 



Inner metatarsal tubercle blunt ; snout 



obtuse 50. temporaria, p. 44. 



