TROPIDONOTUS 



153 



the supraocular, once and one-third to once and a half 

 as long as broad, as long as or a little shorter than 

 its distance from the end of the snout, shorter than 

 the parietals, not in contact with the preocular. 

 Loreal deeper than long. One (rarely two) pre- 

 and three (rarely two or four) postoculars. Tem- 

 porals i-J-2. Upper labials seven (rarely six or 

 eight), third and fourth (or fourth and fifth) entering 

 the eye. Four or five lower labials in contact with 

 the anterior 

 chin -shields, 

 which are 

 shorter than 

 the posterior. 



Scales with 

 two apical 

 pits, in nine- 

 teen rows, 

 strongly 



keeled on the body, of outer row smooth or faintly 

 keeled. Ventral shields 157 to 181; anal divided; 

 subcaudals 50 to 88. 



Coloration. — Very variable. We shall first de- 

 scribe the typical form, and then allude to the 

 principal varieties and individual variations with 

 which we are acquainted. 



Grey, bluish-grey, olive, or brown, above, usually 

 with black spots or narrow bars on the back, and 

 vertical bars on the sides ; upper lip whitish or 



Fig. 16 (after Sordelli) 



