37 



TROPIDONOTUS mGER.—Holbrook. 



Plate IX. 



Characters. Head large, sub-oval; body elongated, rather slender, above 

 dusky brown, at times almost black; throat and neck milky-white; abdomen and 

 tail beneath, slate colour, more or less relieved in the centre with milky-white. 

 PI. 143. Sc. 64. 



Description. The head is large, sub-oval, with the snout rounded. The 

 vertical plate is hexagonal, broadest before, and with an acute angle behind; the 

 superior orbital are oblong, quadrilateral, largest behind, and project over the eye. 

 The frontal plates are broad, hexagonal, and descend outwardly to a large quadri- 

 lateral loral plate; the anterior frontal are rhomboidal and small. The occipital 

 plates are large and pentagonal; the temporal are two in number, and the anterior 

 larger. The rostral is hexagonal, and hollowed out on its inferior face; there are 

 two nasal plates, quadrilateral, the one concave behind and the other before, to 

 accommodate the nostril. There is a single large anterior orbital and two small 

 posterior orbital plates; the inferior portion of the orbit is completed by the fifth 

 and sixth labial plates, of which there are eight, quadrilateral and large. 



The nostrils are near the snout, and open a little upwards and outwards. The 

 eyes are large, with the pupil black, and the iris smoky-grey. The neck is 

 contracted. 



The body is long and more slender than in any other of our water-snakes, and 

 is covered above with hexagonal, carinated scales, notched at their posterior 

 extremities. The tail is long and triangular. 



