From odous, odontos, a tooth.
| Anodon, | Toothless. |
| Boodon, | Ox tooth. |
| Cynodon, | Dog’s tooth. |
| Deirodon, | Neck tooth. |
| Dinodon, | Double tooth. |
| Glyphodon, | Grooved or carved tooth. |
| Heterodon, | Abnormal tooth. |
| Isodon, | Equal toothed. |
| Lycodon, | Wolf’s tooth. |
| Ogmodon, | Furrowed or grooved tooth. |
| Oligodon, | Few toothed. |
| Rachiodon, | Spine toothed. |
| Sepedon, | Noxious tooth, or a tooth causing putridity. |
| Tomodon, | Stump tooth. |
| Xenodon, | Strange tooth. |
In Dumeril’s system very many families, including sometimes several of the above, are grouped according to their teeth, thus:—
| Aglyphodontes, | Teeth not carved or notched. |
| Holodontes, | Whole or entire teeth. |
| Anholodontes, | Without whole or entire teeth. |
| Aproterodontes, | Without front teeth. |
| Isodontiens, | With even teeth. |
| Apistoglyphes, | Grooved at the back, or the back teeth grooved. |
| Proteroglyphes, | Grooved in front, or the front teeth grooved. |
| Solenoglyphes, | Cut or carved with a canal. |
And some others whose names are equally descriptive.
These various characters, with the exception of Aproterodontes, which refers to the under jaw, have reference to the upper jaw only. It might be tedious to the reader to enter into a minute description of each of the above groups: sufficient for our present purpose is it to show that such varieties exist, and that a simple, even row of teeth, as a family distinction, is oftener the exception than the rule. Some of the teeth increase in size posteriorly, others are largest anteriorly; others, again, are larger towards the middle of the jaw, and decrease at either end. Some harmless snakes have ‘fangs,’ that is to say, fang-like teeth, but not connected with any poison gland, and at the back instead of the front of the jaw. Again, there are some non-venomous species that have the power of moving these fang-like teeth, raising or depressing them as vipers move their fangs, and as will be further described presently. Some grooved teeth convey an acrid saliva, others are without any modification of saliva, the long teeth being of use in holding thick-skinned prey.
Thus we find every gradation both in number and in form until we come to the true fang, the ‘murderous tooth’ of the terrible cobra, the hydrophidæ, and the viperidæ. And noteworthy it is that the fewer the teeth in the maxillary bone the more terrible are they. Fig. A of the four illustrations given opposite is the jaw-bone of the Indian Rat snake, Ptyas mucosus, already ‘honourably mentioned’ in these pages. The illustration being taken from Fayrer’s Thanatophidia, may be received as a faithful representation. This conveys a good idea of jaws generally in non-venomous snakes of that size, say from six to ten feet long. In some of the smaller kinds the jaw and palate teeth are so fine as to be almost imperceptible to the naked eye. To the touch they feel like points of the finest pins. Draw your finger along or press it against a row of ‘minikin pins,’ and you will form a correct idea of these tiny weapons. I have often felt when I could not see them in the mouth of a small harmless snake. Pass the tip of your little finger gently along them towards the throat, and they are almost imperceptible even to the touch; but in withdrawing your finger against the points, you feel how excessively fine they are.
The accompanying illustrations are from nature, and exemplify the various lengths of jaw in four snakes, not differing very greatly in size.
Four jaws. From Fayrer’s Thanatophidia of India.