1. The Alligator (Crocodiles Lucius, Cuvier) properly so called, which inhabits the fresh waters of the Carolinas, the Mississippi, and other southern parts of the United States, and of whose fierceness and voracity Bertram has related such extraordinary accounts. It grows, according to Catesby, to the length of 14 or 15 feet, the head being one-seventh of the entire length, and half as broad at the articulation of the jaws as it is long. It appears to be more fierce and voracious than the South American species, often attacks men and quadrupeds whilst bathing or crossing the rivers, and is even said to prefer the flesh of the negro to all other food ; probably because the slave is more exposed to its attacks than his master. The alligators prey chiefly by night ; they assemble in vast numbers, besetting the mouth of some retired creek into which they have previously driven the fish, and bellowing so loud that they may be heard at the distance of a mile. To catch the fish they dive under the shoal, and having secured one, rise to the surface, toss it into the air to get rid of the water which they necessarily take in along with it, and catch it again in its descent. When how ever they succeed in capturing a land animal, which is too large to be swallowed at a single mouthful, they conceal the body beneath the bank till it begins to putrefy, for as their teeth are not formed for cutting or masticating, they are unable to tear the tough flesh in its fresh state ; it is then dragged on shore and devoured at leisure. When about to Lay, the female digs a deep hole in the sand, and deposits her eggs in layers, separated from one another by intervening strata of leaves and dry grass. It would appear that she lays only one batch of eggs during the same season, though in the hotter parts of South America, if the report of Laborde is to be depended on, the Cayman, or alligator of Surinam and Cayenne, lays at two or even three different periods of the year ; but as each batch is said to consist of only twenty or twenty-five eggs, if; is probable that the whole does not exceed the number usually assigned to the common alligator. The female of this latter species, it is said, never loses sight of her nest till the young are hatched, and for months afterwards affords them the most unremitting care and protection.
This species is frequently found up the Mississippi higher than the Red River. In general, the alligator of North America buries himself under the mud, at the bottom of the swamps and marshes which he inhabits, as soon as the cold weather fairly sets in, and continues in 9. lethargic sleep till the return of spring. During the very severe frosts,. sensation is so completely suspended, that the body of the animal may be cut into slices without dispelling his lethargy; yet it is never actually frozen, and the partial return of a few hours bright sunshine is at all times sufficient to restore suspended animation. It is particularly iu the rivers, lagoons, and swamps of Florida, Georgia, South Carolina, and Louisiana, that the alligator reaches his greatest dimensions. Bertram found immense numbers of alligators and fish in a mineral spring near the Mosquito River, in Florida, though the water, at its exit from the earth, was nearly at the boiling point, and strongly impregnated with copper and vitriol.
Besides the characters common to all the American crocodiles, this species exhibits the following modifications which distinguish it from others -The snout is flattened on its upper surface, and slightly turned upwards at the extremity; the sides of it are nearly parallel, and the nose forms a regular parabolic curve. It was this similarity to the
head of a pike that gave to the present species the name of Crocodiles Lucius, or the Pike-Headed Crocodile. The internal rim of the orbits is large and protuberant, but without being united by a transverse crest as in the Crocodiles selerops, or Spectacled Alligator. The external openings of the nostrils are separated by a long knob; the skull has two shallow, oblique, oval pits, in the bottom of which are two small holes. On the back of the neck are four principal plates, elevated in the centre into keel-shaped ridges ; and in front and rear of these respectively, two smaller ones of similar form. The back exhibits 18 transverse rows of similar plates, the first with only two crests or ridges, then two with four, afterwards three with six, then six with eight, then again two with six, and finally, the last four rows with four crests each. The ridges or crests on the body are of nearly equal size; species shows not the slightest truce of those post-orbital perforations, which are so conspicuous in the crocodile of the Nile, and more or less developed in all the other species.
those of the tail are much larger, and amount to 3S in all, l9 before the union of the two lateral eeriest, and as many afterwards. The colour is • deep greenish•brown above, and light-yellow on the under surface of the body ; the aides regularly marked with alternate bands of both these colours.
2. The Cayman (Crocodilus prttpebrosus,Curier)is at once distinguished from all other species by the bony structure of the eyebrows, which form large knobs of the size of a man's fist ; and by the small extent of the membrane connecting the toes of the hind feet, which In prepared specimens can scarcely be recognised. The skull of this This is the common species of Surinam and Cuiana: it is there called Cayman, a word most probably of native origin, whilst the following species, which is likewise found in the same countries, though its more appropriate locality would appear to be Brazil and Buenos Ayres, is distinguished by the name of Crocodile. The Cayman does not attain so large a size as the other species, nor will he venture to attack a man on dry land, or even In the water, so long as he keeps his legs and arms in motion. The female deposits her eggs in a single layer, and after covering them slightly with sand, abandons them to the vivifying influence of the tropical sun, without taking any further charge either of them or of the young progeny.
3. The CrocoditPls f rigonat us of Schneider is a species of crocodile, exhibiting all the peculiar characters which properly distinguish the alligators of America, and yet suspected to be of African origin. It is even eo closely allied in form and general characters to the Cayman, Cuvier has described it as a mere variety of that species. The principal distinction between this and the foregoing species consists in a ridge which rises in front of the orbits, and runs towards the snout, and a small notch in the posterior border of the skull ; the second row of cervical plates is larger than the others, and towards its middle are two or three small scales, with irregularly disposed crests; the large ridges assume the form of scalene triangles, which gives the whole animal a rough and bristly appearance ; there are 16 transverse bands on the back, the number of plates appearing to vary according to the species, and from 19 to 28 on the tail, 9 or 10 before the junction of the lateral ridges, and from 10 to 17 afterwards. Nothing whatever is known of the manners or habits of this species or variety.