ASIATIC LIZARDS OF THE OENy« TllOPIDOrilORUS. 77^ 



38. A Review of the Lizards of tlie Genus Iropidophorus 

 on the Asiatic Mainland. By Malcolm A. Smith, 

 M.R.O-S., L.R.C.P., F.Z.S. 



[deceived May 28, 1923 : Read October 23, 1923.] 



Tiiis article concerns those species that ?.re to he found distri- 

 buted througliout the Indo-Chinese peninsula — Burma, Siani 

 and French Indo-Ohina — and the region immediately north — 

 Assam, Yunnan, and soutliern China. Incidentally it completes 

 our knowledge of the whole group, tlie species of the Indo- 

 Australian region and of the Philippine Islands having been 

 recently undertaken by Nelly de Rooij * and Edward H. Taylor f" 

 respectively. 



The whole genus now includes some 18 species. It is essen- 

 tially a highhuid one, and is largely aquatic in its habits. Its 

 members are to be found in the vicinity of rockj' streams, living 

 among the damp herbnge on the banks, or hiding under stones 

 and boulders, sometimes almost completely immersed in the 

 water to which they invariably take to avoid cnpture. They are 

 nocturnal in their habits and are not remarkably agile. One 

 species, 1\ mia-olepis, I have found to be viviparous. 



Different characters have at times been used to group the 

 species, but the one, so far neglected, which appears to mo to 

 present the most natural basis for classification, is the manner in 

 which the scales are disposed along the sides of the body. It 

 divides the genus into two broad groups: (1) those with the 

 lateral scales directed straight backwards, with smooth or keeled 

 dorsal scales and smooth or feebly rugose upper head-shields, and 

 (2) those with the lateral scales directed obliquely upwards and 

 backwards, with strongly keeled, often mucronate dorsal scales 

 and with head-shields always rugose. 



The prajanal shields vary in number, but appear to be constant 

 as regards each species. On the otlier hand, the number of 

 scales round the body shows considerable individual variation, 

 and nnless some other differential character can be shown to 

 exist, does not seem sufficient for specific distinction. 



In coloration the species are all much alike. 



Within the geogrMphical limits discussed in this paper I 

 recognize the following forms : — 

 I. Liiteral sc.iles directed straight backwards. 

 a. llead-sliiolds siiiootli. 



Froiito-iiiisal entire T. herdmorei. 



Fronto-nasal divided T. laotns. 



6. llead-sbields feebly rugose T.robimoni. 



* ' Reptiles of tlie Iiido-Australian Arcbipebigo,' 1915. 

 t 'The Lizards of the rhilipiiiiio Islands,' 1922. 



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