1-40 Proceedings of the Royal Physiccd Society. 



being almost, but not quite, distinctive of the male sex. In 

 one or two anomalous specimens I have seen this colouring 

 in females, but very rarely. The reddish yellow throat is 

 found only in the female, as far as I have seen. These two 

 sexual distinctions extend to the lip scales in a marked 

 degree. Males often have the two anterior upper labials 

 quite black, and the remaining six or seven upper labials 

 black-edged. In females the whole of the upper labials are 

 often whitish or yellowish red. 



The black belly is more often seen in males than females, 

 but not exclusively so. 



The frontal shield and parietal shields are almost always 

 darker in males than females, and in the latter are frequently 

 surrounded by a light green -coloured area, which I have 

 never seen in males. 



Lastly, the brilliant orange on the ventral aspect of the 

 tail is developed irrespective of sex, and its significance is 

 unknown at present. 



