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(Crocodiles.)

The appellation by which this Order is distinguished, derived from the word lorica, signifying a coat of mail, expresses the most obvious peculiarity by which its members may be known, the ridged and bony armour in which they are invested. "The Crocodiles and Alligators of both worlds, and the Gavials of India, which constitute this order, are distinguished," observes Mr. Bell, "from the true Saurians or Lizard tribe, by several important characters. Of these the most tangible and obvious is that upon which the name of the Order is founded; the covering of the whole of the back part of the neck, body, and tail, with distinct series of bones, of modederate size, imbedded, as it were, in the substance of the skin, and covered externally with a thick cuticle. These dermal bones are usually furnished with a crest, which renders them exceedingly strong, and they altogether form a panoply of defence which can resist the attacks of the most powerful enemies of whatever kind."^[1]

The general form of the Loricata agrees with that of the Lizards; but besides the important difference already mentioned, the bony plates run down the body in longitudinal lines, the structure of the skull is much more solid, and the posterior orifice of the body is longitudinal. The tail is ​flattened at the sides; there are five toes before and four behind, of which the innermost three on each foot are armed with claws; the toes are connected by intervening membranes, varying in extent. There is a single row of pointed teeth in each jaw; the tongue is fleshy, flat, and free only at the extreme edge; whence the Crocodile was vulgarly reputed to be without a tongue. The back and tail, as already intimated, are covered by large and strong scales of square form, elevated into a ridge in the middle; the tail is surmounted by a deeply notched or saw-like crest, which is double at the base; the scales of the belly are delicate and smooth. The nostrils are situated at the end of the muzzle, and open by small crescent-form slits, closed by valves; they lead through a long and straight canal pierced in the bones of the palate, to the back of the mouth. The lower jaw is prolonged behind the skull, and this structure causes the upper jaw to seem moveable; but this is simply an illusion. The external ear is closed at pleasure by means of two fleshy lips; the eye is furnished with three lids: two small glandular orifices are placed beneath the throat, whence exudes a musky secretion, the odour of which strongly marks these animals even for years after their dried skins have been preserved in a museum.

The Reptiles of this Order are of large size and great strength; and as they are exclusively carnivorous and predaceous, and very ferocious, they are dreaded, not without reason, in the tropical countries which they chiefly inhabit. Yet these creatures, feared and hated as they are, were not created in vain. "In the grand policy ​of Nature," observes Prof. Jones, "the scavengers are by no means the least important agents. In hot climates, especially, where putrefaction advances with so much rapidity, were there not efficient and active officers continually employed in speedily removing all dead carcases and carrion, the air would be perpetually contaminated with pestilential effluvia, and entire regions rendered uninhabitable by the accumulation of putrefying flesh. Perhaps, however, no localities could be pointed out more obnoxious to such a frightful cause of pestilence, than the banks of tropical rivers—those gigantic streams, which, pouring their waters from realm to realm, daily roll down towards the sea the bloated remains of thousands of creatures which taint the atmosphere by their decomposition."^[2]

Here, then, is the appointed dwelling-place of the Loricata. Lurking in the dense reeds, or tangled herbage that grows rank and teeming at the edges of rivers in hot climates, or under the mangroves that interweave their myriad roots in arches above the water, or concealed among the bleaching trunks and branches of trees that have fallen into the stream, these huge reptiles watch for the approach of a living prey, or feed at leisure on the putrid carcases with which the waters daily supply them. It is even affirmed that they prefer a condition of putrescence in their prey, and that their practice, when not pressed by immediate hunger, is, on seizing a living prey, to plunge into the stream in order to drown it, after which, it is dragged away to some hole, and stored until decomposition has commenced.

​The subjects which compose this Order are few in number, and are all comprised in a single Family, which we shall presently describe more in detail. They are natives of both hemispheres, but are confined to the warmer regions of both, neither Europe nor Australia possessing any known species: they all inhabit fresh waters.