Fig. 6.—Three transverse sections of a poison-fang of one of the Colubridæ, through A A, B B, C C; P P, pulp cavity; V V V, poison-canal (groove). (After C. J. Martin.)
In the Elapinæ sub-family of the Colubridæ, and especially in the Hydrophiinæ, the teeth are much shorter and simply grooved or canaliculate; that is to say, the canal communicates with the exterior throughout its extent by a narrow slit, which traverses the entire convex surface of the tooth (figs. 4, 5, and 6).
It does not follow from this that the bites of these reptiles are less dangerous; the contrary, indeed, is the case, for their venom is infinitely more active.
These differences, as well as the particular mode of arrangement of the other little non-poisonous teeth in both jaws, enable us in many cases to recognise, by the mere appearance of the bite, the species of snake by which the bite has been inflicted.
Fig. 7.—Marks produced on the Skin by the Bites of different Species of Snakes.
I. Non-venomous Colubrine.—The bite is marked only by the imprint of from 35-40 small palatine or pterygoid teeth, and 20-22 upper maxillary teeth (on the outside of the foregoing) on each side.
II. Venomous Colubrine (Naja tripudians, Proteroglypha).—The bite exhibits 25 or 26 punctures from the pterygoid or palatine teeth, and, on each side, one or two, rarely three, circular wounds produced by the principal poison-fangs and by the reserve teeth.