1895.] TEETH OF CEETAIN POISONOCS S>'^AKES. 819 



There were two posterior, almost straight, grooved teeth (PL I. 

 fig, 25), preceded by a few small teeth ^^•hich were larger anteriorly. 

 The mandibular teeth were 10 in number, the 3 anterior ones 

 large and followed by 7 smaller teeth. 



Genus Psammophis. 



Species examined : — P. sehelans. 



The only available specimen of this Snake had been at some 

 period dried, and consequently the teeth only could be examined. 

 The maxilla (PI. XLV. fig. 19) possessed 10 teeth — three anterior 

 small ones followed by a diastema, then two large teeth and three 

 more small ones ; the two posterior teeth were large grooved ones. 

 There were 13 mandibular teeth, 2 anterior large ones and 11 

 very small ones ; the first 3 small ones were separated by wide 

 diastemata, and the 8 posterior ones grouped together. 



Genus Teimeeoehinus. 



Species examined : — T, rhomheatus. 



The poison -gland is here superficially indistinguishable from the 

 superior labial gland, and extends a comparatively long distance 

 posterior to the eye (PI. XLV. fig. 17). The maxilla possesses 

 10 teeth ; the 2 posterior ones are very large and grooved, and the 

 8 anterior ones are much smaller and of uniform size. 



Genus THAJOfODTKASTES. 



Species examined : — T. nattereri. 



The poison-gland is very clearly differentiated from the superior 

 labial gland and exhibits a marked lobulation. The maxilla is 

 somewhat slender and possesses altogether 16 teeth ; the 2 

 posterior ones are large, grooved teeth, and the other 14 are 

 smaller, much attenuated teeth (PL XLV. fig. 15). The grooved 

 teeth possess a small, though marked, posterior cutting-edge 

 (PL XLV. fig. 16). 



The mandibular teeth are also 16 in number, but are not so 

 crowded as the maxillary ones and are more upright. 



Genus Leptodiea. 



Species examined: — L. rufescens and L. annulata. 



The poison-gland of Leptodira rufescens is superficially indistin- 

 guishable from the superior labial gland, and is of a most extra- 

 ordinary form. Just posterior to the eye it has a sudden upward 

 fiexure, and is then continued backwards for a much greater 

 distance than that observed in the gland of any other Opistho- 

 glyphous Snake (PL XLV. fig. 10). Looking at the head from the 

 side, the gland is seen to partially cover the lower portion of the 

 eye; but, to compensate tor this, the head is very broad and the 

 eyes directed obliquely upwards and forwards. The maxilla 



