8 



The tailless Batracliians of Southern India, which, in common with 

 those from other regions, have the posterior extremities considerably 

 longer than the anterior, belong to the three following families : — 



1 . The Ranid(B, or true frogs ; 



2. T\\Q Engijstomatid(B ; 



3. The Bufonidce, or true toads. 



The Ranidw, represented in Southern India by the genera Rana^ 

 Rhacop/iorns, Ixalus, Nyctibatrachus, and NauNobatrachiis, have their 



pectoral arch or girdle 

 constructed on the 

 " Firmisternal " type 

 {v.p. 9), possess teeth in 

 their upper jaw, and 

 the transverse processes 

 of their sacral vertebra 

 are not or only very 

 slightly dilated (pi. I, 

 fig. 4. sv.). 



Some genera, e.g., 

 Rana, have the fingers 

 perfectly free, and the 

 toes more or less com- 

 pletely webbed (fig. J^), 

 while other genera, e.g., 

 Rhacophorus, have the 

 fingers as well as the 

 toes more or less webbed. 

 The feet of many of the 

 Ranidw are provided with 

 one or more metatarsal 

 tubercles ( fig. 4), which 

 may be blunt, sharp, or, e.g., in Rana brericeps, shovel-shaped and well- 

 adajited for digging. 



Many of the Rant'dce lead an arboreal life, and some, e.g., the 



common '^chunam frog " 

 {Rhacophorus macalatus), 

 have well-developed discs 

 at the ends of their 

 fingers and toes (fig. 5), 

 by means of which they 

 are able to stick on to 

 smooth vertical surfaces, 

 such as walls and win- 

 dows. 



Taking as a type of 



the bony skeleton of the 



^W- 5- Ra>iida> the skeleton 



(pis. I and II) of Rana hexadactgJa, a species which is very common in 



tanks and along river banks throiighout Southern India, its leading 



features are as follows : — 



1. The bony skull is large and flattened. On the superior surface 

 (pi. I, 1) may be recognised a large fronto-parietal (fp) formed by the union 



Fiff. 4. 



