Crocodile

Crocodile, a book name for any individual of the order Crocodilia, specially applied to the genus Crocodilus, constituting a family (Crocodilidae), the other members of the order forming the families Alligatoridae and Gavialidae. Crocodiles, in the first and wider sense, are large lizard-like amphibious reptiles, with a crested tail which forms' a powerful swimming organ. The body drags more or less on the ground; there are four short stout limbs, webbed partially or completely, with five digits on the fore-legs and four on the hind, and the back, and in some cases the abdomen, is covered with bony scutes. The teeth are in a single row, set in sockets and hollow at the base, to receive the germs of the new teeth, by which the old ones are from time to time pushed out and replaced. The tongue is flat, and fixed to the base of the mouth, thus giving rise to the erroneous notion that these animals had no tongue. At the back of the mouth are two transverse membranes, which stop the passage of water down the throat when the prey is held beneath the surface to drown. The heart has two auricles, and the ventricle is divided, thus making the heart four-chambered and bringing it up to the level of that of birds. The nostrils lie close together at the extremity of the snout, and can be closed by valves, as can the ears, and a nictitating membrane protects each eye. The lacrymal glands are large, and the copious secretions therefrom have given rise to the notion of "crocodile's tears," and the epithet "crocodilian" has been coined to describe deceitful sorrow, from the old belief that the crocodile shed tears to lure man to his doom. All are oviparous, and the eggs, about the size of those of a goose, are laid in holes in the sand. The order dates from Triassic times, and is divided into two sub-orders: - (1) Proccelia (having the vertebrae concave in front), including all living forms and extinct genera from the Chalk onward; and (2) Amphicoelia (having the vertebra; concave at both ends), including all the extinct genera up to the Chalk. Examples of Alligators, Crocodiles, and Gharials occur in the Eocene beds of the south of England. The genus Crocodilus (True Crocodiles) contains twelve species (some of which have been unnecessarily raised to generic rank), widely distributed in tropical regions. They are found in all the rivers of Africa, and frequent the shores and estuaries of India and Siam, ranging to North Australia, and four of them inhabit the West Indies and Central and South America. The head is longer than that of the alligator, and the fourth tooth in the lower jaw bites into a groove in the upper, and so is visible when the mouth is closed. The hind legs have a kind of scaly fringe, and the toes are completely webbed. Most species are entirely fluviatile, but some frequent brackish water, and two or three take to the sea. They feed largely on fish, especially when young, when full-grown on the smaller mammals, and sometimes successfully attack man himself. The Nilotic Crocodile (C. vulgaris) is widely distributed in Africa, and is said to attain a length of thirty feet; specimens of half that length are in the Natural History Museum, South Kensington. It was worshipped when alive and embalmed when dead by some of the ancient. Egyptians, though others "made them an article of food." A plover (Pluvianus aegyptius) lives in a kind of companionship with the crocodile, clearing its body and, according to Herodotus, its throat of parasites, and warning it of danger by loud cries. The skin, which is tanned for leather, the fat, and the musk-glands of the lower jaw are articles of commerce. C. cataphractus and C. niger are both from the west coast of Africa; the former has a very long thin snout, while the head of the latter is short and broad like that of an alligator. C. porosus, the Salt-water Crocodile, has many of the characters of the common species, and ranges from India to the Fiji Islands and Australia. C. bombifrons, the Marsh Crocodile, often miscalled an alligator, is worshipped in Sind. Other species are the Siamese and Pondicherry Crocodiles (C. siamensis and C. pondicherrianus); the Australian Crocodile (C. johnstoni), with a long slender, conical snout; C. acutus, from Central America and the West Indies, somewhat resembling the extinct Teleosaurs in the shape of the snout; and the Cuba Crocodile (C. rhombifer), distinguished by its convex frontal region.