GERRHOSAURUS BIBRONI. 



between angle of jaw and base of hinder leg, well developed. The scales of 

 the back and sides quadrangular, and disposed in transverse rows, each with a 

 strong keel along its centre, and others less developed towards the sides. 

 Scales of the upper and lateral portions of the tail similarly shaped to those of 

 the body, but have only the central keel, which forms a projecting point be- 

 hind ; mental plate large and semicircular behind ; to this plate succeed 

 four other plates, the two hinder ones the largest ; the throat and breast 

 are coated with large imbricate somewhat six-sided scales, broadest trans- 

 versely, and arranged in longitudinal rows. The plates of the belly are dis- 

 posed in transverse rows, eight in each, are of a quadrangular form and per- 

 fectly smooth. Scales of the lower surface of the tail rather long, narrow, and 

 slightly rounded at the point. Fore legs slender and covered with smooth, 

 imbricate, somewhat six-sided scales ; hinder legs anteriorly and inferiorly 

 with scales of a like description only larger, posteriorly, with small triangular 

 ones strongly carinated, the carina forming the apex of each ; scales on soles 

 of feet small and slightly granular. Femoral pores twelve, and nearly quite 

 concealed by the row of plates immediately in front of them. Preanal plates 

 three in a row, the central one triangular with its apex pointing backwards. 

 Toes of fore feet short and slender, the inner, that which corresponds to what 

 is called the great toe, shortest, the second considerably longer, the third the 

 longest, the fourth a little shorter than the third, and the outermost rather 

 longer than the innermost. The third and fourth toes of the hinder feet are 

 much longer than those of the fore feet, and the third exceeds considerably in 

 length the fourth ; the outer and second toes are also much longer than the 

 corresponding ones of the fore feet. 



Inches. Lines. 

 Length from the nose to the base of 



the tail 4 6' 



ofthetail 6 6 



from nose to meatus externus 9 



DIMENSIONS. 



Inches. Lines. 



Length from nose to base of fore legs 11 



Distance between fore and hinder legs 3 



Length of fore legs to toes 9 



of hinder legs to toes 1 2 



Female.— As regards the colouring the two sexes are nearly alike, but the 

 female is more robust than the male, and the tail proportionally shorter. 



The only specimens of this Lizard which I have seen, were obtained towards the sources of 

 the Caledon, one of the principal branches of the Orange River. They were all discovered in 

 the dark and shaded ravines which form breaks in the Quathlamba mountains, and when 

 they were pursued they sought concealment under the dead leaves and decaying wood which 

 abounded in the ravines in question. 



