128 Records of the Indian Museum. [Vol. XX. 



First finger much shorter than second; tibia 14' times 

 as length from snout to vent ; toes nearly entirely 

 webbed ; head longer than broad ; tympanum -} dia- 

 meter of eye . . ... ... ..O :R. mearnsii, Stejn. 



2. Glandular dorso-lateral fold absent ,■ toes entirely or nearly entirely webbed. 

 a. Tympanum very distinct, ^ to \ diameter of eye ; discs of fingers not 

 broader than long. 



a. Tibio-tarsal articulation reaching between eye and nostril ; belly granu- 



late. 



Tibia 5 times as long as broad, it times in length from 



snout to vent; first finger as long as second ; tym- ,j > 



panum a diameter of eye; back smooth ..//., R. everetti, Blgr. -' / O '-^'^j^ ,^ ' 



Tibia 2^ times in length from snout to vent ; first finger 

 longer than second ; tympanum .j diameter of eye ; 



head and back very rough with large tubercles ... /?. ishikava, Stejn./' -^ '' 

 B. Tibio-tarsal articulation reaching beyond tip of snout; tibia li to if 

 times in length from snout to vent. 



First finger as long as second ; tibia 5! to 6 times as 

 long as broad ; tympanum | diameter of eye; belly 

 smooth ... ... ... ..IJc R. crassiovis, Blgr. / 



First finger shorter than second ; tibia 6 times as long 

 as broad ; tympanum f diameter of eye ; belly granu- 

 late ... ... ... ... ..: ^' R. katnpetii,B\gr. ^ ^ ,v-v,-/J. 



First finger as long as or longer than second . tym- 

 panum ^ to f diameter of eye ; belly granulate ; male 

 with external vocal sacs ... ... ..l~CR. livida, ^Xyih.A ^1 '/ : 



b. Tjmpanum more or less distinct, or obscured by granules, not J dia- 



meter of eye ; discs of fingers very large, often broader than long, 

 with a transverse groove on the upper surface, corresponding to the 

 long horizontal limb of the terminal phalan.\ ; first finger as long as 

 or shorter than second. 

 a. Third finger not more than twice as long as snout_ first with well- 

 developed terminal disc; foot shorter than tibia. 

 Snout shorter than eye ; tibio-tarsal articulation reaching 

 tip of snout or not quite so far ; tibia 35 to 4 times as 



long as broad, ij to 2 times in length from snout to , vVr ?!-■ ■.: 



vent; male without vocal sacs ... ..-- R.ricketti, Blgr./ 



Snout as long as eye ; tibio-tarsal articulation reaching 

 beyond tip of snout ; tibia 4 to 55 times as long as 



broad, if to i§ times in length from snout to vent; ^ 



male with external vocal sacs ... .,.', R. latopalmata, Blgr./. ■S '7hi/ 



ft. Third finger more than twice as long as snout. '' ■ 



\'omerine teeth present ; first finger with the tip merely 



swollen ; tibio-tarsal articulation reaching beyond tip 



of snout ; tibia 4 to 4i times as long as broad, I5 to l\ 



times in length from snout to \ent ; foot shorter than 



tibia; male with internal vocal sacs ... /,^~ R. himal^iyana, Blgr./ ~'?S-5' 



Vomerine teeth present ; first finger with the tip merely 

 swollen ; tibio-tarsal articulation reaching nostril or 

 tip of snout ; tibia 47, to 55 times as long as broad, 

 i| to ij times in length from snout to vent; foot as 



long as or slightly shorter than tibia ; male with inter- , ij 



nal vocal sacs ... ... ... ..'.■' R./ormosa, Gthv./ -' 



\'omerine teeth absent ; first finger with well-developed fiv»vj»' 



terminal disc ; tibio-tarsal articulation reaching tip of 

 snout or slightly beyond ; tibia 4 times as long as 

 broad, if to if times in length from snout to vent ; ., 

 foot shorter than tibia ... ... .... R. Iiaiiianensis, Blgr.,- 



The classification of the numerous species included in this 

 subgenus presents great difficulties. A linear arrangement is best 

 based on the degree of specialization of the fingers and toes, as 

 expressing the general drift of evolution, and this has been 



