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The species of snakes most dangerous to man are found in the warmer regions of Asia. India especially is infested by the famous Cobra-di-Capello (Naja tripudians), which possesses the highly remarkable faculty of dilating its neck in the form of a hood when irritated, and whose sculptured image appears on almost all the Hindu monuments.

We shall describe in a separate section (see below, F.) the Hydrophiinæ, or Sea-snakes, a large number of species of which frequent the shores of the Indian Ocean, the Strait of Malacca, the China Sea, the Moluccas, Celebes, and North Australia. In the case of certain species the area of distribution includes the whole of the tropical and sub-tropical zones of the Pacific Ocean, as far as the West Coast of America. It is therefore preferable to group them together for the purpose of comprehensive study.

Besides the above, the continent of Asia harbours a multitude of poisonous snakes belonging to the two Families Colubridæ and Viperidæ.

The genera and species belonging to these are so diverse, that we must confine ourselves to mentioning the essential characters of those that present most interest.

I.—Family Colubridæ.
Subfamily Elapinæ: Genera
{ (a) Bungarus.
{ (b) Naja.
{ (c) Hemibungarus.
{ (d) Callophis.
{ (e) Doliophis.

(a) Bungarus.

Head hardly distinct from the neck; eyes small, with round or vertically elliptic pupils; nostril between two nasal shields. Two large poison-fangs followed by one or two small, slightly grooved teeth (fig. 23). Scales smooth, oblique, in 13–17 rows, enlarged and hexagonal in shape on the vertebral column; ventral scales round. Tail relatively short; subcaudal scales in one or two rows.

Two very dangerous snakes found in India and Indo-China belong to this genus, B. fasciatus and B. candidus (var. cæruleus). Both are fairly common. In Ceylon B. ceylonicus is met with, and in South China B. candidus (var. multicinctus). The length of these snakes is from 1,000–1,500 millimetres. The back is compressed in the shape of a keel. The neck is not dilatable.

Fig. 23.—Skull of Bungarus. (After G. A. Boulenger, op. cit.)