REPTILES. 277 



is fixed to each superior maxillary bone. When not in use, 

 they lie flat upon the roof of the mouth, concealed by a fold 

 of the skin. In each fang is a channel, which opens, not at 

 the point of the tooth, but near to it, by a longitudinal fissure. 

 Through this passage the poison flows. When the animal is 

 irritated the poison-fangs are erected in a moment ; and when 

 they are struck into the victim, it is easy to imagine how 

 forcibly the poison must be injected into the wound; for the 

 powerful muscles which elevate the lower jaw serve at the 

 same time to compress the poison-bag. 



Behind the large poison-fang in actual use arc the germs 

 of several others, ready to supply its place if accidentally 

 broken off, each of which is soon " adapted in all respects to 

 take upon itself the terrible office of its predecessor." 



The poison itself is neither acrid nor burning. On the 

 tongue it only produces a sensation like that of fatty matter, 

 and it may be swallowed without danger; but introduced into 

 the blood in sufficient quantity, it causes death with fearful 

 rapidity, though the power varies, according to the species and 

 other circumstances. To avoid such consequences, the best 

 precaution is that which is adopted in these countries for the 

 bite of a dog supposed to be mad: the immediate cutting out 

 and cauterising of the wounded part. 



In one genus of the poisonous Serpents there exists a pro- 

 vision which puts the unwary on his guard, and discloses the 

 proximity of the dangerous reptile. We allude of course to 

 the Rattle-snake (Fig. 223). Its tail is terminated by a 

 series of horny rings, loosely put together, which rattle with 

 the slightest movement of the animal, and even with the 

 vibrations of the tail when the creature itself lies in conceal- 

 ment.* 



Among the venomous Serpents is one which possesses a 

 classical and historical interest, associated as it is with the 

 death of Cleopatra the Egyptian Naja or Asp (Fig. 226). 

 It is at present much used by the Egyptian jugglers in their 

 exhibitions. One of a nearly allied species, the Cobra-di- 

 Capello, has a curious mark on the skin of the neck, not unlike 

 a pair of spectacles. A specimen of this Snake was pre- 

 sented to the Belfast Museum, by Major Martin (now residing 



* The information here given respecting the poisonous Serpents is 

 almost entirely derived from Jones's Outline, Carpenter's Zoology, and 

 Milne Edwarcls's " Elemens de Zoologie." 



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