Poisonous Snakes of British Guiana. 403 



anterior, grooved, or perforated fangs in connexion with the 

 poison-glands. The members of a very large section of what 

 are commonly termed harmless snakes are, however, really 

 poisonous to a certain extent, possessing grooved posterior 

 fangs, the bite from which is capable of paralyzing or killing 

 the small prey on which they feed. On man this bite pro- 

 duces, at any rate in certain cases, an effect quite independent 

 of the mechanical injury. This the writer personally expe- 

 rienced in the case of the common species of Erythrolamprus 

 (E. 03sculapii=E. venustissimus) , as recorded in f Timehri,' 

 vol. vi. new series (1892), p. 174. Three bites from the 

 snake were received on the first finger, the posterior fangs 

 being driven down deeply into the flesh each time, and after 

 a short interval very considerable swelling and severe pain 

 resulted, which was only relieved after about four hours, 

 though the place was tender for a much longer time. 



A similar effect on man is certainly produced by the bite of 

 some Colubrine snakes which are destitute of grooved teeth. 

 This has been directly noted by the writer in the case of two 

 species with enlarged elongated posterior teeth, namely 

 Xenodon severus and Helicops angulatus } where the teeth were 

 driven deeply down into the flesh, and it would appear that 

 ill effect is only caused by a large wound of a great degree of 

 penetration admitting matter from the buccal glands, which 

 would be impossible in a bite of slight or only moderate 

 depth. An interesting relation between the two groups is 

 seen in forms of the common species of Erythrolamprus, in 

 which certain specimens are destitute of the groove on the 

 posterior fangs. 



The foregoing cases may serve to explain the peculiarity 

 of the very large number of instances in which persons have 

 been said to have been bitten by the common forest pit- viper 

 or labarria and have recovered, and the extreme simplicity of 

 the remedies used, such, for instance, as sugar and salt, 

 paraffin oil, onion poultice, external application of ammonia, 

 and other such substances, some of which may certainly be 

 efficacious in allaying pain and lessening inflammation, but 

 would have no real effect in dealing with a case of a lethal 

 dose of snake- poison, especially after the more or less long 

 intervals which usually elapse before such applications can be 

 made. In certain cases, no doubt, the snakes may have been 

 labarrias whose glands may not have been fully charged and 

 whose bite would therefore not inject sufficient poison to kill; 

 but in the great majority of cases it may be taken for granted 

 the snakes were really not deadly, though perhaps capable of 

 producing a certain amount of inflammation and more or less 



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