THE VIPER. 438 
Like most reptiles, whether poisonous or not, the Viper is a very timid 
creature, always preferring to glide away from a foe rather than to attack, 
and only biting when driven to do so under yreat provocation. 
The head of the Viper affords a very good example of the venomous 
apparatus of the poisonous serpents, and is well worthy of dissection, 
which is better accomplished under water than in air. The poison-fangs 
lie on the sides of the upper jaw, folded back and almost undistinguishable 
until lifted with a needle. They are singularly fine and delicate, hardly 
larger than a lady’s needle, and are covered almost to their tips with a 
muscular envelope through which the points just peep. The poison- 
secreting glands and the reservoir in which the venom is stored are found 
at the back and sides of the head, and give to the venomous serpents that 
peculiar width of head which is so unfailing a characteristic. The colour of 
the poison is a very pale yellow, and its consistence is very like that of salad 
oil, which, indeed, it much resembles, both in look and taste. There is but 
little in each individual, and it is possible that the superior power of the 
VIPER, OR ADDER.—(P:lias' Berus.) 
large venomous snakes of other lands, especially those under the tropics, 
may be due as much to its quantity as its absolute intensity. In a full-grown 
rattlesnake, for example, there are six or eight drops of this poison, whereas 
the Viper has hardly a twentieth part of that amount. 
On examining carefully the poison-fangs of a Viper, the structure by 
which the venom is injected into the wound will be easily understood. On 
removing the lower jaw, the two fangs are seen in the upper jaw, folded 
down in a kind of groove between the teeth of the palate and the skin of 
the head, so as to allow any food to slide over them without being pierced 
by their points. The end of the teeth reach about halfway from the nose to 
the angle of the jaw, just behind the corner of the eye. 
Only the tips of the fangs are seen, and they glisten bright, smooth, and 
translucent, as if they were curved needles made from isiuglass, and almost 
as fine asa bee’s sting. On raising them with a needle or the point of the 
forceps, a large mass of muscular tissue comes into view, enveloping the 
tooth for the greater part of its length, and being, in fact, the means by 
which the fang is elevated or depressed. When the creature draws back its 
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