in the Collection of the British Museum. 363 



54 in the female. All the lower parts are yellowish, each ventral 

 shield having a blackish base. 



An adult (pregnant) female is 17^ inches long, the tail measur- 

 ing 4 inches. All our other specimens are still smaller, although 

 mature. This species inhabits S.W. Australia, whilst H. super- 

 bus proves to be a Tasmanian species. 



Tropidechis. 



Mr. Krefft has described a very interesting Snake from the 

 Clarence River district as Hoplocephalus carinatus^. Although 

 it agrees in other points with the species of that genus, the 

 scales have quite the same structure and arrangement as in Tro- 

 pidonotus — a point by which this species appears to me to be 

 entitled to generic distinction, and I propose the name of Tro- 

 pidechis for this new type. 



Atractaspis aterrima. 



Entirely deep black. Trunk slender, the circumference of, 

 its anterior portion being contained twenty-three times in the 

 total length ; ventrals 274 ; subcaudals simple, 20. Scales in 

 21 series. Two pairs of frontal shields ; one prse- and one post- 

 ocular; five upper labials; temporals 1 + 1, the anterior very 

 large, four-sided, partly intercalated between the fourth and fifth 

 labials. 



West Africa. This species is very similar to A. Bibronii, from 

 which it may be readily distinguished by its coloration, by its much 

 more slender body, and by the increased number of ventral 

 shields, — A. Bibronii having only 225-255. Our specimen is 

 14 inches and 2 lines long, the tail measuring 7 lines. 



I have formerly identified A. Bibronii with Elaps irregularis, 

 Reinh. (Colubr. Snak. p. 239). Both are, indeed, extremely 

 similar to each other ; but as Reinhardt speaks of scutella cauda- 

 lia, it is possible that they are different, the term " scutella " 

 usually implying that the subcaudals are paired, and not simple. 



Causus [Heterophis) rostratus. 



Rostral shield turned upwards, forming a prominent, sharpish, 

 transverse ridge above ; scales in seventeen rows ; a series of large 

 spots along the back. 



The rostral shield has a flat oblique inferior surface, and 

 forms above a curved, prominent, transverse ridge; it termi- 

 nates posteriorly in a triangular process intercalated between 

 the front part of the anterior frontals. The nostril is be- 

 tween three shields, viz. between a narrow longish anterior 

 nasal, a small square posterior nasal, and the anterior frontal ; 

 * Proc. Zool. Soc. 1863, p. 86. 



24* 



