LIFE, IN ITS HIGHER FORMS.

No. III. (continued.)

REPTILES.

THERE may often be seen on sunny banks at this season of the year, basking in the genial beam of noon, a little Reptile, well known under the appellations of Blind-worm and Slow-worm. As it lies motionless, you might almost fancy it a foot's length of thick iron wire, slightly polished, for it is almost equal in thickness in every part, and its surface gleams with a metallic lustre in the bright sun. Here is the village apothecary coming up the lane, poring over a book with spectacles on nose; let us ask him if he can tell us anything about it. "O yes it is the Anguis ! fragilis of Linnæus !" and he passes on. Oh! the Brittle Snake! for such is the English of those two Latin words.

But here is Hodge the hedger: perhaps from his occupation he may have some acquaintance with the bit of dingy wire what say you, Hodge? ""Tis a Zneak, dang 'un !" and he makes a spiteful blow with his stick across the back of the poor animal, with the apologetic asseveration," "Tis a deadly pizon varmin!" But see, the blow has effectually demolished it, and that in a strange manner; for, as if it had been made of glass, it has snapped across in four or five places; and we at once perceive the propriety of one of its Latin appellations, that of "fragilis."

Science and ignorance agree, then, that the Slow-worm is a Snake; but science and ignorance are both mistaken, for the creature is a Lizard. The assertion seems paradoxical, when we think of the two pairs of well-developed limbs, each armed with five jointed and clawed toes, that

the Lizard possesses, and of the way in which it uses them to scamper away from our intrusion beneath the heath and furze; but it is true that the slender, limbless, snake-like Slow-worm is, in all the most important points of its anatomy, a Saurian, and not a Serpent. Undoubtedly it is one of the links by which these two very diverse forms are bound together, and, like all such links, forms a most interesting subject of study. The degeneration and gradual disappearance of the limbs, in the progress of the various genera that, like so many stepping-stones, bridge over the wide passage from the Lizard to the Serpent, are phenomena peculiarly worthy of observation; and we cannot do better, in bringing them before our readers, than to quote the words of the eloquent historian of "British Reptiles," in his account of this very Slow-worm :

"From the well-known family of the Scinks, or Scincida, with their true legs and five-toed feet, down to the present species and its immediate congeners, every possible gradation is to be found in the development of the interior and posterior extremities. Agreeing, as they all do, in the Saurian character of the structure of the head, the consolidation of the bones of the cranium and jaws, and the narrow and confined gape, so different from these parts in the true Serpents, they yet approach the latter in the comparative length of the bodies, and in the gradual diminution and ultimate disappearance of the extremities. In the genus Scincus, for instance, the limbs are already less robust than those of the true Saurians; the two pairs are also more distant from each other, in consequence of the greater comparative elongation of the body. There are as yet five perfect toes on each foot, which, however, are shorter and more even in their relative proportions than in the true Saurians. These deviations become increased in the genus Chalcides, and still more in Seps, which has a very

elongated body, the limbs extremely small, and the toes only four or three on each foot. In Monodactylus a further reduction takes place in the development of the limbs, which have dwindled to a mere little undivided finger; they are still, however, four in number; but in the genus Bipes the anterior ones have wholly disappeared, and are found in a rudimentary state under the integument, the posterior ones constituting only small undivided processes. These also being removed, the Ophidian form of the present genus, and those of Tortix, Typhlops, and others, with all the Amphisbanidæ, succeed, in which the bones of the shoulder, the sternum, and the pelvis, exist in a more or less rudimentary condition, and lead us towards the true Snakes, in which all these parts are lost, excepting the rudiment of a posterior extremity, which in the Boa appears externally in the form of a small horny hook, or holder, on each side of the vent."*

Besides the Slow-worm, we have in the British Isles but two representatives of the vast Lizard group,- the Order Sauria. One of these is the elegant Sand Lizard of our sandy heaths (Lacerta agilis), which is beautifully marked along the sides with eye-like spots, and sometimes occurs of a rich variegated green hue. The other is the smaller, but more common Viviparous Lizard (Zootoca vivipara), whose interesting peculiarity is expressed in its name, that of producing a living progeny, most Reptiles laying eggs. The difference between these two conditions is, however, less important than it at first appears; for there is every reason to believe, that in this case, as well as in that of the Viper (Pelius berus), which is also viviparous, the egg-covering, which is merely a parchment-like membrane, and very thin, is ruptured in the act of parturition.

The most remarkable genus in this Order, and indeed *"British Reptiles," p. 40.

in many respects the most extraordinary and anomalous of all Vertebrate animals, are the Chameleons, of fabulous and poetic celebrity. They are Lizards inhabiting trees in the warmer countries of the Old World, with a great development of head, and a shagreened skin. As the Monkeys of South America are fitted for their arboreal habits by grasping hands and a prehensile tail, so is the Chameleon, by a curious modification of the common Lizard organization. The toes are five, as in the majority of Saurians, but these are arranged in two sets, three in one set and two in the other, each set being enveloped in the common skin as far as the claws. These two parcels of toes are opposed to each other, and thus each foot forms a true grasping hand, and is used in the manner which this structure indicates; the Chameleon moving with slow and deliberate steps, always grasping with a firm hold the branch on which it is creeping, before the other feet are relaxed for a fresh step. The tail is round and prehensile at the tip, like that of the American Monkeys; its under surface is roughened with small granulated papillæ, as is that of the toes also, probably in order to the more delicate perception of the surface grasped. The tongue affords an analogy to the same organ in the Woodpeckers, no less singular than that of the feet; for though ordinarily concealed within the mouth, it is capable of being darted forward at its insect prey, and, being furnished with a glutinous secretion, secures it by its adhesiveness.

A most extraordinary aspect is communicated to these Reptiles by the structure and movements of their eyes. In the first place, the head is enormous, and being threesided with projecting points and angles, makes a sufficiently uncouth visage; but the eyes which illuminate this notable head-piece must, indeed, to borrow for the nonce the phraseology of Barnum, "be seen to be appreciated."

There is on each side an immense eye-ball, full and prominent, but covered with the common shagreened skin of the head, except at the very centre, where there is a minute aperture, corresponding to the pupil. These great punctured eye-balls roll about hither and thither, but with no symmetry. You cannot tell whether the creature is looking at you or not; he seems to be taking what may be called a general view of things;-looking at nothing in particular, or rather, to save time, looking at several things at once. Perhaps both eyes are gazing upwards at your face; a leaf quivers behind his head, and in a moment one eye turns round toward the object, while the other retains its upward gaze; presently a fly appears, one eye rapidly and interestedly follows all its movements, while the other leisurely glances hither and thither, or remains steady. Accustomed as we are to see in almost all animals the two eyes move in unison, this want of sympathy produces an effect most singular and even ludicrous.

The Lizards are not in all cases the little leaping, timid, playful creatures that we commonly associate with the name. The aquatic Monitors (Varanida), of both continents are truly formidable. M. Leschenault de Latour saw one attack a young stag as it attempted to swim across a river, striving hard to drown it. The deer was too active on this occasion, but the same zoologist found the thigh-bone of a sheep in the stomach of one that he dissected. The tail in this group is very muscular, and is compressed throughout its length; it thus forms a powerful swimming organ, especially as its upper edge is frequently surmounted with a crest of flattened elevated scales. These large and powerful Lizards, which are often five feet in length, and stout in proportion, usually endeavour to overcome their prey by dragging it into a river and drowning it.

In all these particulars we see an approach to those