Зображення сторінки
PDF
ePub
[graphic]
[ocr errors]

usually with a nictitating membrane.

The body is elongated, and generally of a somewhat cylindrical form, terminated posteriorly with a very long, tapering tail, which is often much longer than the body. The feet are well developed, and generally furnished with five distinct toes of unequal length. The teeth are a little curved, and inserted in a slight furrow of the jaw; they are hollow at the base, and are not very firmly attached to the bone. These Lizards, which must be regarded as the types of the Sauria, are confined to the countries of the eastern hemisphere, over the whole of which they are pretty generally distributed. They feed on insects and

worms.

Genus LACERTA: Lacerta.-To this belongs the NIMBLE LIZARD, L. agilis-the Sand-Liz

ard of England, Lézard of the French: it is seven inches long; color brown, though there are green varieties. It inhabits sandy heaths, runs with agility, is very timid, but will attempt to bite when captured. The female lays twelve to fourteen eggs, which she covers with sand, and leaves them to be hatched by the heat. Found in France, England, and the middle countries of Europe; is rare in Denmark and Sweden.

[graphic]

Genus ZOOTOCA: Zootoca, includes the COMMON EUROPEAN LIZARD, Z. vivipara, six inches long; greenish-brown above; orange beneath, spotted with black. The female of this species, instead of depositing her eggs in the sand and leaving them to be hatched by the heat of the sun, produces them alive, five or six in number, perfectly formed, and capable of at once running about. She however bestows upon them a mother's care for a brief period. This is a graceful and gentle species, and is capable of being tamed. It seems to be confined to Middle Europe; it is found in England, Scot

THE SAND LIZARD.

land, and even in Ireland, an evidence that St. Patrick, who has the credit of having destroyed the reptiles in the favored Emerald Isle, must have confined his operations to the venomous species.

The OCELLATED LIZARD, L. ocellata, is a very beautiful species, a foot in length, of a fine green color, reticulated and spotted with black, and adorned with blue spots on the side of the body. It is abundant in Italy, Spain, the south of France, and Africa.

THE AMEIVIDE.

These, which are American animals, seem to take the place of the Lacertidæ upon this continent. They resemble them in their general characteristics, but differ in having solid teeth, firmly attached to the jaws. They live on the ground in woods and hedges, and feed principally upon insects, though they sometimes devour small vertebrate animals.

Genus TEIUS: Teius.-This includes the TEGUEXIN or VARIEGATED LIZARD, found in Brazil

THE VARIEGATED LIZARD.

and Guiana. It sometimes measures six feet in length, and is very voracious, preying upon mice, frogs, and other small animals; it is said occasionally to visit the poultry-yards, and to feed on the chickens and eggs. Its flesh is white, and not unlike that of a fowl in flavor. When pursued it does not allow itself to be taken without a struggle; it runs with great swiftness, and strikes such violent blows at the dogs with its tail, that they do not readily venture to attack it. When brought to bay, it

[graphic]

fights boldly, and inflicts severe bites upon any thing that comes within its reach. It is fond of honey, and attacks the bee-hives with blows of its tail, each time, after having given a stroke, running away to escape the stings. In this way it wearies out the bees, who finally quit their home and leave the honey to their enemy.

Genus AMEIVA: Ameiva.-These are elegant and inoffensive little lizards, abounding in the West Indies; one species is found in the United States, from Carolina to Florida: this is the SIX-LINED LIZARD, A. sexlineata, dark brown above, with six yellow longitudinal lines; length twelve inches. A species called A. tessellata is said to be found in Arkansas.

THE VARANIDÆ.

These, which are called the Broad-backed Lizards, and derive their name from the genus Varanus, comprise the largest species of known lizards; they resemble the preceding families in the form. of their bodies, and in the constant development of the limbs, but differ from them in having the head and belly covered with scales resembling those of the rest of the body, instead of the shield-like plates which form the clothing of those parts in the Lacertidæ and Ameividæ. The head is elongated, and the tongue, which is very long and distinctly bifid, like that of a snake, is received at the base in a membraneous sheath. The tail is very long, usually compressed and keeled, and the feet large, and furnished with long toes terminated by strong claws. They run swiftly, with a serpentine motion; and feed on locusts, crickets, and beetles, and some of the larger species on the eggs of birds and crocodiles, chameleons, fish, and tortoises.

Genus MONITOR: Monitor, includes several species. The EGYPTIAN MONITOR, M. Niloticus, attains the length of five or six feet; it lives in the neighborhood of water, and is said to devour the eggs of crocodiles; common in Egypt, where the people hold it to be a dwindled crocodile. It is figured on the ancient monuments.

Genus HELODERMA: Heloderma.-To this belongs the CALTETEPON, H. horridum, which is distinguished by furrowed fangs in the anterior portion of its jaws. It is aquatic in its habits, VOL. II.--48.

It is the only

and is found in Mexico, where it is considered venomous, though this is an error. animal of this family found in America. Dr. Gray arranges it in a separate family, to which he gives the name of Helodermida.

There are other species of Varanidæ in Europe, Asia, Africa, and Australia, which frequent dry and sandy places. The Psammosaurus scincus is found in the deserts of Egypt, and is supposed to be the skink of the ancients.

[graphic]

THE WALL GECKO.

THE GECKOTIDÆ.

These, as well as the succeeding families are called Thick-tongued Lizards. Of the present group there are a great many species, distributed in various parts of the world. They have the eyes large and the legs short and terminated by five nearly equal toes; these are destitute of claws, but they are furnished beneath with a peculiar apparatus for clinging, very similar in its action to that by which many insects are enabled to walk upon polished perpendicular surfaces. The lower part of each toe is dilated, forming a sort of disc, the inferior surface of which is composed of numerous transverse, notched laminæ, between which a sticky fluid exudes. By means of this apparatus the Geckos are enabled to run up a perpendicular wall with great facility, and even to cross a ceiling with their backs downward, a power which, no doubt, assists them greatly in the capture of the flies and other insects which constitute their principal food. They are nocturnal animals, and very active, moving about with great rapidity, but without the least sound. They are very abundant in warm climates, especially in Southern Asia. They are generally of a repulsive appearance, and this is no doubt the reason why many of the species are considered venomous, though erroneously so, by the inhabitants of the countries where they are found. Genus PLATYDACTYLUS: Platydactylus.-This includes the WALL GECKO, P. muralisone of the species known in the south of Europe, and inhabiting all the countries bordering on the Mediterranean. It is about six inches long, and receives its specific name from living in the walls of old buildings. The term Gecko is said to be derived from the note of one of the species.

Genus THECADACTYLUS: Thecadactylus.—This includes the CROAKING LIZARD of the West Indies, T. laevis, which frequents the sugar-boiling houses, reposing during the day upon the rafters. It is generally considered venomous, but this is undoubtedly a result of its repulsive appearance.

THE IGUANIDÆ.

These constitute another exceedingly numerous family. They are frequently of considerable

THE COMMON IGUANA.

size; the head is unusually broad and flattened, and often furnished with comblike ridges or membraneous lobes, and similar appendages are usually continued along the back. The throat, also, is almost always furnished with membraneous expansions of some kind; these sometimes constitute large frills on the sides of the neck. The eyes are always furnished with lids, which can be completely closed; the ears are freely exposed, and the tongue is short and thick, and free only at the tip. Many of the species are of the most brilliant green color, but they suddenly change this gay painting on being alarmed, and become of more sober coloring; some of them, under these circumstances become completely black.

[graphic]

Genus IGUANA: Iguana.-This includes the COMMON IGUANA, I. tuberculata, which may be regarded as the type of the family; it is a large lizard, which attains a length of four or five feet, and is common in all the tropical parts of America. It is of a greenish color, mottled with a brighter green, and banded with brown on the tail; along the back runs a comb-like crest, and the throat is furnished with a large membraneous expansion, which is also denticulated in front. This reptile is much sought after in the countries where it abounds, its flesh being regarded as a great delicacy, although it is said not to be particularly wholesome. It passes a great part of its existence in trees, and is commonly taken when resting on a branch, by slipping a noose over its head, its captor whistling to it while engaged in the operation. Its teeth have the crowns compressed and serrated, and it lives principally upon fruits and seeds. It is said to take the water freely, and to swim with facility.

Genus BASILISCUS: Basiliscus.-The BASILISK, B. Americanus, although perfectly harmless, is certainly one of the most hideous of reptiles in its appearance. It is found in South America, and occasionally attains a length of upward of three feet. Instead of the comb-like dorsal ridge of the Iguana, it is furnished with a broad membrane running down the back, and a second, still broader, on the upper surface of the tail, and these are supported by a series of bones, consisting of the elongated spinous processes of the dorsal and caudal vertebræ, and having the appearance of long perpendicular fins.

THE AGAMIDÆ.

These seem to take the place of the Iguanas in the Old World. They are principally inhabitants of the warmer regions of Asia and Australia, and the intervening islands; a few are found in the south of Australia, Van Diemen's Land, and New Zealand, and a few others in Africa, from Egypt to the Cape of Good Hope. One remarkable genus is found in the United States. In their general form, and in the character of their peculiar appendages, they closely resemble the American Iguanas; but some of them are particularly remarkable. One of these is the Chlamydosaurus Kingii, which is not uncommon in the neighborhood of Port Essington. The appearance of this lizard is most extraordinary; it is furnished with a curious crenated membrane, forming a šort of frill or tippet round its neck, and covering its shoulders. Each side of this singular appendage is furnished with four cartilaginous plates, by means of which it can be folded

or extended, in the manner of a fan, at the pleasure of the animal. It measures about two feet in length; it is a bold creature, fighting fiercely when pursued, and always extending its broad ruff when in circumstances of irritation or danger.

A still more remarkable development of the dorsal system is presented by the Flying Dragons, of which three species are known in India and the Asiatic Islands. They live on trees, upon which they run about in search of insects, on which they feed. These are furnished with a broad membraneous lobe on each side, supported by six first false ribs, which are extended straight outward from the vertebral column. By the movements of these bones the dragons are enabled to stretch their broad lateral membranes, which thus form a sort of parachute to support them in long leaps from branch to branch. They are, however, quite destitute of any power to strike the air, so that their flight is in fact nothing but a floating through the atmosphere. They are small harmless creatures, seldom exceeding a foot in length.

The flying dragons of the older writers were fabulous creatures, and their descriptions are known to have been, in some instances, founded upon articles manufactured for the express purpose of duping credulous naturalists.

Some other species of the Agamidæ are worthy of notice. Among them we may mention

DOUGLASS'S PHRYNOSOMA.

the Stellio vulgaris, a common lizard in the Levant, and also in Egypt, where its excrements were formerly collected and used as a cosmetic. Cuvier states that the Mahometans destroy this animal wherever they see it, because, as they say, it insults them by bowing its head in imitation of their motions when engaged in prayer. Another singular species, from Australia, has been described by Dr. Gray under the name of Moloch horridus. The whole surface of this lizard is covered with irregular plates and strong acute spines, and the upper surface of the head bears two very large spines. Altogether it is a most hideouslooking creature.

Genus PHRYNOSOMA: Phrynosoma.-This includes DOUGLASS'S PHRYNOSOMA, P. Douglassii, found at Salt Lake Valley, by Captain Stansbury, from whose work we copy the annexed engraving. It is three and a half inches long, and olive-green above. The head is covered with sharp spines or roundish knobs; the body is scattered over with irregular spine-like scales. It is sluggish in its habits, and has some resemblance to a toad, whence this, with other species— of which there are five or six, in California, Utah, and the Southwestern States-are called Horned Toads.

[graphic]

THE CHAMELEONTIDÆ.

Genus CHAMELEON: Chamæleo.-This is the only genus of the family, but it contains about eighteen known species, all inhabitants of the Old World, and which are, perhaps, the most singular in the whole order of lizards. They are all small animals, with a curious pyramidal, and unusually angular head, distinctly separated from the neck, a short, thick body, which gradually tapers from the region of the shoulders to the point of insertion of the hind-legs, and a short prehensile tail. The mouth is very large; the teeth are firmly attached to the jaws; the ears are entirely concealed under the skin, and the eyes, which are very large and prominent, are closely covered by a circular lid, which is only perforated by a small round opening immediately in front of the pupil. The legs are rather long and slender; the feet are composed of five toes, which, however, are divided into two opposite bundles, and the toes of each bundle are so united

« НазадПродовжити »