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All poisonous snakes are carnivorous. They feed on small mammals (rats, mice), birds, batrachians, other reptiles or fish, which they kill by poisoning them by means of their fangs.

They almost always wait until their prey is dead before swallowing it.

Some of them are very fond of eggs, which they well know how to find in the nests of birds, and swallow whole.

When a poisonous snake wishes to seize its prey, or strike an enemy, it raises its head, and depresses the lower and elevates the upper jaw in such a way that the fangs are directed straight forward. Then, with the quickness of a spring when it is released, the reptile makes a sudden dart and strikes its victim. After inflicting the wound it draws back, doubles up its neck and head, and remains prepared to strike again.

So rapid is the action of the venom, that the wounded animal falls to the ground almost immediately; it is forthwith stricken with paralysis, and dies in a few moments. In most cases the snake holds it in its mouth until death ensues; the reptile then sets to work to swallow its victim, an operation which is always slow and painful.

In captivity poisonous snakes almost always refuse to take any food whatever. If it be desired to keep them for a long time, it is often necessary to resort to artificial feeding. For this purpose the snake is seized by the head by means of a strong pair of long forceps; it is then grasped by the neck with the left hand without squeezing too hard (fig. 15), taking care at the same time not to give the body a chance of coiling itself round anything. Next, one or more lumps of beef or horse-flesh are introduced into the jaws, and gently forced down deep into the œsophagus by means of a glass rod, which is polished in order not to injure the mucous membrane. The œsophagus is then gently massaged in a downward direction, in order to cause the bolus of food to descend into the stomach (fig. 16). This operation is repeated every fortnight.

Fig. 15.—Feeding a Poisonous Snake, First Stage.

Fig. 16.—Feeding a Poisonous Snake, Second Stage.

Fig. 17.—Catching a Cobra-di-Capello (Naja tripudians), First Stage. (At the French Settlement of Pondicherry, in India.)

In this way, at my laboratory, I have been able to preserve, in perfect condition for more than two years, Indian Cobras and Fers-de-lance from Martinique, taking care to keep them in a hothouse, at a temperature of about 82° to 86° F.

It is also very important to place inside the cases a vessel full of water, which should be frequently changed, for almost all snakes drink often and like to bathe for whole days at a time.

Fig. 18.—Catching a Cobra-di-Capello (Naja tripudians), Second Stage. (At the French Settlement of Pondicherry, in India.)

Within their reach should be placed in addition branches and rockwork, against which they rub at the moulting times, in order periodically to rid themselves of their scarf-skin.

While moulting, snakes must neither be touched nor fed, since to force them to take food at such a time would be fatal.

Snake-catching.—The capture of poisonous snakes, in order to keep them alive, can only be performed without danger by skilful persons, who are possessed of much coolness.

The best way of securing them is suddenly to pin the neck to the ground by means of a stick held horizontally, or a small two-pronged fork of wood or metal (fig. 17).

The stick is rolled along until close to the occiput (fig. 18). The animal can then be seized with the hand immediately behind the head, in such a way that it is impossible for it to turn and bite. It is then put into a wire cage, provided with a small movable trapdoor, with the fastening on the outside.

In this way poisonous snakes can be sent to a distance, and left without food for one or even two months, provided that they be kept in a place which is somewhat moist and sufficiently warm.

Fig. 19 shows how captured cobras are carried in India, in the environs of Pondicherry. They are enclosed in earthern chatties, or in baskets of plaited bamboo, which are provided with covers, and are very convenient for carrying snakes short distances.

Fig. 19.—Hindu carrying Two Captured Cobras in “Chatties.”