Cobra (Naja tripudians), a poisonous Colubrine snake, belonging to the family Elapidae, known also as the hooded snake, cobra di capello or naga. In this genus the anterior ribs are elongated, and by raising and bringing forward these, the neck can be expanded at will into a broad disk or hood. It possesses two rows of palatine teeth in the upper jaw, while the maxillary bones bear the fangs, of which the anterior one only is in connexion with the poison gland, the others in various stages of growth remaining loose in the surrounding flesh until the destruction of the poison fang brings the one immediately behind to the front, which then gets anchylosed to the maxillary bone, and into connexion with the gland secreting the poison, which in the cobra is about the size of an almond. Behind the poison fangs there are usually one or two ordinary teeth. The cobra attains a length of nearly 6 ft. and a girth of about 6 in.
The typical cobra is yellowish to dark-brown, with a black and white spectacle-mark on the back of the hood, and with a pair of large black and white spots on the corresponding under-surface. There are, however, many varieties, in some of which the spectacle markings on the hood are wanting. The cobra may be regarded as nocturnal in its habits, being most active by night, although not unfrequently found in motion during the day. It usually conceals itself under logs of wood, in the roofs of huts and in holes in old walls and ruins, where it is often come upon inadvertently, inflicting a death wound before it has been observed. It feeds on small quadrupeds, frogs, lizards, insects and the eggs of birds, in search of which it sometimes ascends trees. When seeking its prey it glides slowly along the ground, holding the anterior third of its body aloft, with its hood distended, on the alert for anything that may come in its way. “This attitude,” says Sir J. Fayrer, “is very striking, and few objects are more calculated to inspire awe than a large cobra when, with his hood erect, hissing loudly and his eyes glaring, he prepares to strike.” It is said to drink large quantities of water, although like reptiles in general it will live for many months without food or drink. The cobra is oviparous; and its eggs, which are from 18 to 25 in number, are of a pure white colour, somewhat resembling in size and appearance the eggs of the pigeon, but sometimes larger. These it leaves to be hatched by the heat of the sun. It is widely distributed, from Transcaspia to China and to the Malay Islands, and is found in all parts of India, from Ceylon to the Himalayas up to about 8000 ft. above the level of the sea.
Closely allied is N. haje, the common hooded cobra of all Africa, the Spy-slange, i.e. spitting snake of the Boers.
The cobra is justly regarded as one of the most deadly of the Indian Thanatophidia. Many thousand deaths are caused annually by this unfortunately common species, but it is difficult to obtain accurate statistics. The bite of a vigorous cobra will often prove fatal in a few minutes, and as there is no practicable antidote to the poison, it is only in rare instances that such mechanical expedients as cauterizing, constriction or amputation can be applied with sufficient promptitude to prevent the virus from entering the circulation. Owing to a small reward offered by the Indian government for the head of each poisonous snake, great numbers of cobras have been destroyed; but only low-caste Hindus will engage in such work, the cobra being regarded by the natives generally with superstitious reverence, as a divinity powerful to injure, and therefore to be propitiated; and thus oftentimes when found in their dwellings this snake is allowed to remain, and is fed and protected. “Should fear,” says Sir J. Fayrer, “and perhaps the death of some inmate bitten by accident, prove stronger than superstition, it may be caught, tenderly handled, and deported to some field, where it is released and allowed to depart in peace, not killed” (Thanatophidia of India). Great numbers, especially of young cobras, are killed by the adjutant birds and by the mungoos—a small mammal which attacks it with impunity, apparently not from want of susceptibility to the poison, but by its dexterity in eluding the bite of the cobra. Mere scratching or tearing does not appear to be sufficient to bring the poison from the glands; it is only when the fangs are firmly implanted by the jaws being pressed together that the virus enters the wound, and in those circumstances it has been shown by actual experiment that the mungoos, like all other warm-blooded animals, succumbs to the poison. In the case of reptiles, the cobra poison takes effect much more slowly, while it has been proved to have no effect whatever on other venomous serpents.
In the Egyptian hieroglyphics the cobra occurs constantly with the body erect and hood expanded; its name was ouro, which signifies “king,” and the animal appears in Greek literature as ouraios and basiliscus. With the Egyptian snake-charmers of the present day the cobra is as great a favourite as with their Hindu colleagues. They pretend to change the snake into a rod, and it appears that the supple snake is made stiff and rigid by a strong pressure upon its neck, and that the animal does not seem to suffer from this operation, but soon recovers from the cataleptic fit into which it has been temporarily thrown.
The cobra is the snake usually exhibited by the Indian jugglers, who show great dexterity in handling it, even when not deprived of its fangs. Usually, however, the front fang at least is extracted, the creature being thus rendered harmless until the succeeding tooth takes its place, and in many cases all the fangs, with the germs behind, are removed—the cobra being thus rendered innocuous for life. The snake charmer usually plays a few simple notes on the flute, and the cobra, apparently delighted, rears half its length in the air and sways its head and body about, keeping time to the music.
The cobra, like almost all poisonous snakes, is by no means aggressive, and when it gets timely warning of the approach of man endeavours to get out of his way. It is only when trampled upon inadvertently, or otherwise irritated, that it attempts to use its fangs. It is a good swimmer, often crossing broad rivers, and probably even narrow arms of the sea, for it has been met with at sea at least a quarter of a mile from land.