NAIA HAJE.—Merrem. 



Reptilia.— Plates XVIII., XIX., XX., and XXI. 



N. flava ant purpureo-brunnea ; partibus inferioribus pallidioribus saepe maculis transversis rubro-brunneo- 

 notatis ; figura subcylindracea, versus caudam fortiter attenuate. 



Longitedo inter 5 et 6 pedes. 



Echidna flava, Merr. Tentam. System. Ampb. p. 154. 



Naia nigra, Smith. Magazine of Natural History, vol. ii. 1838. 



Geel copell, Bruin copell, and Spuugh-slang of the Cape colonists. 



Colour. — The majority of the specimens of this species, which are found 

 in South Africa, are either entirely yellow or purplish brown, though a 

 considerable number occur, also, in which both these colours exist more or 

 less distinctly in the same individual. The depth of the general colour 

 varies considerably in different specimens, particularly in those exhibiting 

 the yellow colour, being observed of every shade between straw-yellow and 

 clear reddish yellow. In specimens which are partly of a yellow and partly 

 of a purplish brown colour ; the latter tint is generally found upon the head, 

 neck, and upper parts of the tail. In all the three kinds, the upper parts 

 are always of a deeper tint than the lower parts, and in the majority of speci- 

 mens the belly is mottled, from being more or less crossed by irregular 

 blotches, or incomplete bars of a reddish brown colour. The abdominal 

 plates, and the subcaudal scales have a slight pearly lustre, and in some 

 they approach almost to a pearly white. 



Form, &c. — Figure nearly cylindrical, with the belly a little flattened ; the 

 greatest thickness of the body is rather nearer to the head than the tip of the 

 tail, and from the thickest part it tapers towards both extremities, the 

 decrease in thickness occurring more rapidly, and to a much greater degree, 

 towards the latter than the former ; so that the tail towards the tip is scarcely 

 so thick as a common writing quill. The head is considerably wider than the 

 neck, the greater width arising principally from the lateral bulge which exists 

 on each side of the hind head, and which gives to this snake its peculiarly 

 hideous and savage appearance. The width of the head is much greater than 

 its depth : its upper surface is flat, and the occipital scales appear very large 



