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ribs were distinctly felt upon the palm, as the animal passed over it. This was an interesting discovery, as it tended to demonstrate a new species of progressive motion, and one widely different from those already known.-Notes to Blumenbach.

Of all animals, serpents possess by far the greatest number of ribs; which amount, in some, to 250 pairs.

Why have snakes a bag between the nose and the eye? Because they have no glands to supply the skin with moisture from within, but receive it by coming in contact with moist substances: it is possible, therefore, that the bags in the snake may be supplied in that manner, and the more so, as the cuticular lining appears perfect. Another peculiarity is remarkable in snakes so furnished; namely, an oval cavity, situated between the bag and the eye, the opening into which is within the inner angle of the eyelid, and directed towards the cornea, (or transparent membrane to protect the anterior surface of the eye.) In this opening there are two rows of projections, which appear to form an orifice capable of dilatation and contraction. From the situation of these oval cavities, they must be considered as reservoirs for a fluid, which is occasionally to be spread over the cornea; and they may be filled by the falling of the dew, or the moisture shaken from the grass through which the snake passes.-Sir E. Home.

Why are scales of different colours?

Because they derive their colours from the mucus web on which they are placed, and this differs in various animals.

The composition of scales, observes Dr. Fleming, is similar to that of the cuticle, with the addition of some earthy salts. They appear to be inserted in that layer of the skin, and to resemble it in many of their properties. When rubbed off, they are easily renewed, and frequently experience the same periodical reno

vations as the cuticle. In reptiles, scales occur on every part of the body, and are placed laterally in some; whilst in others they are imbricated like the slates of a house. In fishes, the scales are usually imbricated, with the epidermis enveloping their base, and the other edge free. They may also be observed on many insects, exhibiting great varieties of form. What are termed feathers on the wings of butterflies, seem to be a variety of scales.

Why are serpents said to leap?

Because they fold their bodies into several undulations, which they unbend all at once, according as they wish to give more or less velocity to their motion.

The body of some serpents is thrown by the muscles into a very rigid state, when irritated; in which condition it breaks into fragments by the slightest stroke.

Why do many serpents easily swim?

Because they have very long and bladder-like lungs, and the hinder part of the body and tail is much depressed.

Why do some serpents twist their bodies round the branches of trees, or suffer a considerable portion to hang down.

Because, in this attitude, the larger kinds are ready to fall down upon the prey passing beneath, such as deers and antelopes. Such animals are not only retarded by their weight, but incommoded by the for twisting itself in wreaths round their body, and by contractile efforts crushing it to death.

Why are serpents so speedily extirpated in civilized countries?

Because, not only is man their inveterate personal foe, but he receives powerful support from many of the domestic animals which accompany him in his dispersion over the globe. The hog is not afraid to give battle to the most venomous; and, in general,

comes off victorious. The goat likewise readily devours the smaller kinds of serpents, and hence the proverb from the Gaelic, "like the goat eating the serpent,"-importing a querulous temper in the midst of plenty.-Fleming.

Why are snakes supposed to fascinate other animals? Because they may more readily entice and secure them for food. Such is the opinion of Professor Silliman, from his observation of two birds who were enticed, and not pursued, by a large black snake in America. "What this fascinating power is," observes the Professor, "whether it be the look or effluvia, or the singing by the vibration of the tail of the snake, or any thing else, I will not attempt to determine-possibly this power may be owing to different causes in different kinds of snakes.

Dr. Hancock, in a recent contribution to Jameson's Journal, however, combats this opinion of the fascination of serpents, by saying, "it is not a faculty of charming or of fascinating, in the usual acceptation of the term, which enables certain serpents to take birds; but, ou the contrary, the hideous forms and gestures, which strike the timid animals with impressions of horror, stupefying them with terror, and rendering them unfit for any exertion; especially as those serpents to which has been ascribed the power of fascinating, are among the most terrific of the tribe.

Why are dragons represented in fable with ringed bodies?

Because they originated in the ringed snake, which, even in Europe, has been found ten feet in length and upwards. Its colour is steel-gray, wherefore the dragon is often so coloured.

Why are venomous serpents distinguishable from those which are not so?

Because of the poison-teeth, which are placed on the anterior edge of the upper jaw, with the corres

ponding increase in the size of the latter; while, in the harmless serpents, the whole of the outer edge of the upper jaw is furnished with teeth, even to the very back part. From the German.

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Among the other characters of distinction, are the broader and heart-shaped head of the venomous, with small flat scales, instead of a single plate; tail-shaped ridge on the back; and the shorter tail, which measures less than one-fifth of the animal.Dr. Gray, in Philos. Transac.

The number of known venomous species, compared to those which are not so, is reckoned as one to six. Why are the fangs of some serpents called poison fangs?

Because they contain a tubular cavity from their base (where is the poison bag) passing through a tooth on its convex side, to the apex, where it ends in a narrow slit. When the serpent bites an animal, the poison flows from the bag through this slit, into the bottom of the wound, where to most advantage it can produce its deleterious effects. The properties of the poison continue even after it has been dried. If instilled into the wound, in any quantity, and it enters any of the larger vessels, death speedily follows. The virulence of the poison depends not only on the species of serpent, but on its condition at the time, and the habit of body of the animal which has received the bite.

Why is the cobra di capello also called the hooded snake?

Because, when irritated, the skin on the neck is expanded and drawn forwards, and appears behind the head as a kind of hood. This motion is produced by the cuticular muscles of the neck, aiued by the movable ribs.

Why do the snake-catchers of India handle with impunity the most venomous serpents?

Because they rub their hands, previously to taking

hold of the snake, with an antidote composed of pounded herbs, the virtue of which is such, that they hold with the naked hand, and provoke fearlessly, the deadly cobra di capello. The secret is not unknown in China; and the cobra, in common with other serpents of a similar nature, are often exhibited in Canton.

Why are vipers distinguished from snakes?

Because vipers bring forth their young alive, whereas, snakes hatch their young from eggs, in dunghills, &c.

THE RATTLESNAKE,

Why is the rattle-snake so called?

Because it has a series of cups appended to its tail; which cups, when the serpent moves its body, likewise move one upon another, and make a rattling noise, not unlike the folding of dried parchment. This noise is said to be audible at the distance of twenty yards, and is thus useful in giving warning of the approach of the destructive reptile, to which it is attached. Its bite is attended with frightful consequences, as in the following instance:-"An emigrant family inadvertently fixed their cabin on the shelving declivity of a ledge, that proved a den of rattle-snakes. Warmed by the fire on the hearth of the cabin, the terrible reptiles entered in numbers, and, of course, in rage, by night, into the room where the whole family slept. As happens in those cases, some slept on the floor, and some in beds. The reptiles spread in every part of the room, and mounted on every bed. Children were stung in the arms of their parents, and in each other's arms. Most of the family were bitten to death; and those who escaped, finding the whole cabin occupied by these horrid tenants, hissing and shaking their rattles, fled from the house by beating off the covering of the roof, and escaping in that direction."-Flint's Geogra phy and History of the United States.

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