Page:Encyclopædia Britannica, Ninth Edition, v. 22.djvu/212

 196 SNAKES fact, however, that the snakes of this sub-order agree in the absence of the small shield on the side of the snout, the so-called "loreal"; and this is all the more remarkable as the same shield has by no means a similar taxonomic significance in the non-venomous snakes, many of which are Cobras, without it, although it is present in the majority. No snake of this sub-order is more widely known and more dreaded than the species of the genus Naja or cobras. Probably more than two species should be distinguished; but the two which cause the greatest loss of life are the Indian Cobra or Cobra di Capello or Naga (N. tripudians) and the African Cobra (N. haje). In a report to the Bengal Government the commissioner of Burdwan states that he has ascertained from statistics collected during a series of nine years that above 1000 persons are killed annually by snakes in a population of nearly 6,000,000, the majority being bitten by the cobra, which is by far the most common. And other districts in India seem to suffer still more severely, although it is difficult to obtain information of all the accidents caused by snakes. The cobra is found throughout India, extending westwards to the Sutlej and eastwards to the Chinese island of Chusan ; in the Hima- layan alps it reaches an altitude of 8000 feet ; it occurs also in abundance in many of the islands of the East Indian Archipelago, and is here joined by another apparently dis- tinct species (N. sputatrix), whilst in the central portions of Asia, which geographically separate it from the African cobra, it is replaced by a fourth, N. oxi- ana. The Indian cobra appears in many varieties of colour, which are distinguished by separate names in the nomenclature ground colour FIG. 13. Head of cobra. Of the Hindu snake-charmers. The varies from a yellowish olive to brown and to black with or without whitish or white crossbands on the back, and with from one to four or without any black bars across the anterior part of the belly. Some of these varieties are characterized by a pair of very con- spicuous white, black -edged spectacle -like marks on the expansible portion of the neck, called the "hood"; but these marks may lose their typical form and become merely a pair of ocellated spots, or be confluent into a single ocellus, or may be absent altogether. All these varieties, however, are the same species, which generally attains to a length of 5 feet, but sometimes exceeds 6. It is more of nocturnal than of diurnal habits, feeding on every kind of small Ver- tebrates and also eating eggs. The cobra and the other species of this genus have the anterior ribs elongated, and can move them so as to form a right angle with the spine. The effect of this movement is the dilatation of that part behind the head which is generally ornamented with the spectacles or ocelli. When the cobra is irritated or excited it spreads its " hood," raising the anterior third of the body from the ground, gliding along with the pos- terior two-thirds, and holding itself ready to strike forwards or sidewards. All accounts agree that the cobra is not aggressive unless interfered with or impelled by a sense of danger. It is said to share the habitations of man where superstition prevents people from molesting it, and to live peaceably with the inmates ; and there is no doubt that professional snake-charmers exercise a certain control over them, for, although generally the cobras exhibited are rendered harmless by the removal of the poison-fangs, they very rarely attempt to injure their masters even after the fangs have been reproduced. Of the natural enemies of the cobra, the mongoos (see vol. xii. p. 629) does probably the greatest amount of execution ; many are destroyed by fowls shortly after being hatched. The cobra is oviparous, depositing from eighteen to twenty -five eggs in the year. The African cobra is extremely similar to its Indian con- gener in size, form, and habits, and varies in coloration to the same extent. It inhabits the whole of Africa, from Egypt to the Cape of Good Hope, but has been nearly exterminated in the cultivated districts of the Cape Colony. One of its greatest enemies (as indeed of all snakes) is the secretary bird of South Africa (Serpentarius), which, there- fore, is protected by law. Accidents from this snake do not appear to be of common occurrence ; they happen more frequently to domestic animals than to man. 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 Geoffroy St-Hilaire main- tains 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. More dangerous than either of the species of cobra, Ophw- which it exceeds in size, is Hamadryas or Ophiophagus phofffs elaps, the largest poisonous snake of the Old World, elaps ' attaining to a length of 14 feet. It has almost the same geographical range as the cobra, but is much scarcer ; it greatly resembles it also in general habit, but differs from it in scutellation, possessing three large shields behind the occipitals. It has the reputation of occasionally attacking and pursuing man ; its favourite food consists of other snakes. Snake-charmers prize it highly for exhibition on account of its size and its docility in captivity, but are always careful to extract the fangs. It lives in captivity for many years. The species of Bungarus, four in number, are extremely Bun- common in India,Burmah, and Ceylon, and are distinguished garums. by having only one row of undivided sub-caudal shields. Three of the species have the body ornamented with black rings, but the fourth and most common (B, coeruleus), the " krait " of Bengal, possesses a dull and more uniform coloration. The fangs of the bungarums are shorter than those of the cobras, and cannot penetrate so deeply into the wound. Their bite is therefore less dangerous and the effect on the general system slower, so that there is more prospect of recovery by treatment. Nevertheless, according to Fayrer, the krait is probably, next to the cobra, the most destructive snake to human life in India. Several genera of this sub-order of Venomous Colubrines Narrow- are similar to the innocuous Calamariidse, in general habit; mouthed that is, their body is of a uniform cylindrical shape, s P ecies - terminating in a short tail, and covered with short polished scales ; their head is short, the mouth rather narrow, and the eye small. They are the tropical American Elaps, the Indian Callophis, the African Poecilophis, and the Australian Vermicella. The majority are distinguished by the beautiful arrangement of their bright and highly ornamental colours ; many species of Elaps have the pattern of the so-called coral snakes, their body being encircled by black, red, and yellow rings, a pattern which is peculiar to snakes, venomous as well as non-venomous, of the fauna of tropical America. Although the poison of these narrow- mouthed snakes is probably as virulent as that of the pre- ceding, man has much less to fear from them, as they bite only under great provocation. Moreover, their bite must be frequently without serious effect, owing to their narrow mouth and the small size of their poison-fangs. They are also comparatively of small size, only a few species rarely exceeding a length of 3 feet.