VI FERINE FANGS. 373 



and the ' involution ' described in the last chapter. A paper 

 on this subject by Thos. Smith, Esq., F.R.S., was read before 

 the Royal Society in 181 8. Mr. Smith claims to have been 

 the first to observe this involution as beincf altofjethcr 

 different from the perforation of the pulp originally supposed 

 to be the case. He first noticed the slit in a cobra's fang 

 (he being in India), and afterwards in a Hydrus (sea snake), 

 and it led him to further investigations. With a microscope 

 the slit was perceptible in a rattlesnake fang (which was also 

 observed by tlie present writer before reading this account). 



One more paper in the FJiilosopJiical Transactions on this 

 subject must be commended to the interested student. It is 

 the one already quoted (p. 363), 'On the Succession of Poison 

 Fangs,' by Charles Tombes, M.A., vol. clxvi. p. 470, 1S76. 

 In this paper is presented the result of all the most recent 

 investigations, enriched by still deeper researches, but of too 

 scientific a character to be introduced in this simple narrative 

 of the progress of ophiology. We may, however, say that 

 Mr. Tombes finds the character or function of succession 

 differs in .the vipers from that of the venomous colubrincs ; 

 and this, as the construction of their fangs and maxillary 

 jaw differs, is what we might look for. 



A few more words descriptive of the external aspect of 

 the VipcridcB may summarize what has already been said of 

 them. Schlegel suggests that their 'noxious character is 

 expressed in all their parts.' With the exception of brilliant 

 colouring, this may be accepted as a rule. The broad, flat, 

 angular head, rendering the 'neck' thin and conspicuous, 

 lias gained for man\- of them the generic, sometimes specific 

 name of Trigonoccphalns. From their deadly qualities, 



