between these larger marks are disposed many smaller ones of uncertain forms, and more or less numerous in different parts; the ground-colour itself is also scattered over by a great many small specks, of the same colour with the variegations; the exterior edges of all the larger spots and markings are commonly blackish, or of a much deeper cast than the middle part, and the ground colour immediately accompanying the outward edges of the spots is, on the contrary, lighter than on other parts, or even whitish, thus constituting a general richness of pattern, of which nothing but an actual view of a highly-coloured specimen of the animal itself can convey a complete idea. In larger specimens, the yellow tinge is often lost in an uniform grey cast, and the red tinge of the variegations sinks into a deep chesnut; and in some the general regularity of the pattern before described is disturbed by a kind of confluent appearance; the head is always marked above by a large longitudinal dark band, and by a narrower lateral band passing across the eyes towards the neck.

The boa constrictor is a native of Africa, India, the larger Indian islands, and South America, where it chiefly resides in the most retired situations in woody and marshy regions.

It was, in all probability, an enormous specimen of this very serpent that once diffused so violent a terror amongst the most valiant of mankind, and threw a whole Roman army into dismay. Historians relate this surprising event in terms of considerable luxuriance. Valerius Maximus thus mentions it from Livy, in one of the lost books of whose history it was related more at large.

"And since we are on the subject of uncommon phænomena, we may here mention the serpent so eloquently and accurately recorded by Livy ; who says, that near the river Bagrada, in Africa, a snake was seen of so enormous a magnitude as to prevent the army of Attilus Regulus from the use of the river; and after snatching up several soldiers with his enormous mouth, and de. vouring them, and killing several more by striking and squeezing them with the spires of its tail, was at length destroyed by assailing it with all the force of military engines and showers of stones, after it had withstood the attack of their spears and darts: that it was regarded by the whole army as a more formidable enemy than even Carthage itself; and that the whole adjacent region being tainted with the pestilential effluvia proceeding from its remains, and the

waters with its blood, the Roman army was obliged to remove its station: he also adds, that the skin of the monster, measuring 120 feet in length, was sent to Rome as a trophy."

The learned Frienshemius, in his Supplementa Liviana, has attempted a more ample and circumstantial narrative of the same event, and it cannot be unacceptable to the reader to receive a quotation from an author who has so happily imitated the manner of the great historian.

"In the mean time Regulus, every where victorious, led his army into a region watered by the river Bragrada, near which an unlooked-for misfortune awaited them, and at once affected the Roman camp with considerable loss, and with apprehensions still more terrible; for a serpent of prodigious size attacked the sol. diers who were sent for water, and while they were overwhelmed with terror, and unequal to the conflict, engulphed several of them in its enormous mouth, and killed others by writhing round them with its spires, and bruising them with the strokes of its tail: and some were even destroyed by the pestilential effluvia proceeding from its breath: it caused so much trouble to Regulus, that he found it necessary to contest the possession of the river with it by employing the whole force of his army, during which a consi. derable number of soldiers were lost, while the serpent could neither be vanquished nor wounded; the strong armour of its scales easily repelling the force of all the weapons that were di. rected against it; upon which recourse was had to battering en. gines, with which the animal was attacked in the manner of a fortified tower, and was thus at length overpowered. Several discharges were made against it without success, till its back being broken by an immense stone, the formidable monster began to lose its powers, and was yet with difficulty destroyed; after hav ing diffused such a horror among the army, that they confessed they would rather attack Carthage itself than such another mon. ster: nor could the camp continue any longer in the same station, but was obliged to fly; the water, and the whole adjacent region, being tainted with the pestiferous effluvia. A most mortifying humiliation to human pride. Here, at least, was an instance of a whole Roman army, under the command of Regulus, and universally victorious both by sea and land, opposed by a single snake, which conflicted with it when living, and even when dead obliged

it to depart. The proconsul, therefore, thought it no diminution to his dignity to send the spoils of such an enemy to Rome, and to confess at once the greatness of his victory, and his terror by this public memorial: for he caused the skin of the snake to be taken off, aud sent to the city, which is said to have measured 120 feet: it was suspended in a temple, and remained till the time of the Numantine war."

[La Cepede. Friensheim. Shaw.

SECTION X.

Cerastes, or Horned Snake.

Coluber cerastes.-LINN.

THE cerastes or horned viper, which commonly grows to the length of about a foot or fifteen inches, and sometimes to a larger size*, is distinguished by a pair of horns or curved processes, situated above the eyes, and pointing forwards: these horns have nothing analogous in their structure to the horns of quadrupeds, and are by no means to be considered in the light of either offen. sive or defensive weapons: they increase, however, the natural antipathy so generally felt against the serpent tribe, and give the ani. mal a more than ordinary appearance of malignity. The cerastes is a native of many parts of Africa, and is principally found in sandy deserts and dry places. Its usual colour is a pale yellowish or reddish brown, with a few rather large, distant, round, or transversely oblong spots of a deeper colour dispersed along the upper parts of the body, the belly or under part being of a pale lead colour. In Syria and Arabia the cerastes is particularly fre. quent, and is also found in many parts of Egypt, &c. It bears a very great affinity to the common viper, and its bite is perhaps still more to be dreaded, since exclusive of the general danger of treading accidentally on this reptile, and thus irritating it unawares, it is said to possess a propensity of springing with great suddenness to a considerable distance, and assailing without provocation those who happen to approach it.

The general history and manners of this serpent are amply de.

The specimens described by Cepede measured more than two feet, as does also that in the British Museum.

tailed by Mr. Bruce, who, in the course of his travels, had fre. quent opportunities of contemplating it in its native regions.

"The cerastes," says Mr. Bruce," inhabits the greatest part of the Eastern Continent, especially the desert sandy part of it, It abounds in the three Arabias, and in Africa. I never saw 50 many of them as in the Cyrenaicum, where the Jerboa is frequent in proportion. He is a great lover of heat; for though the sun was burning hot all day, when we made a fire at night, by digging a hole, and burning wood to charcoal in it, for dressing other vic. tuals, it was seldom we had fewer than half a dozen of these vi. pers, who burnt themselves to death by approaching the embers. The general size of the cerastes, from the extremity of its snout to the end of the tail, is from thirteen to fourteen inches; its head is triangular, very flat, but higher near where it joins the neck than towards the nose: the length of its head, from the point of the nose to joining of the neck, is ten twelfths of an inch, and the breadth nine twelfths: between its horns is three twelfths: the opening of its mouth, or rictus oris, is eight twelfths: its horns in length three twelfths: its large canine teeth something more than three twelfths and a half: its neck, at the joining of the head, four twelfths the body, where thickest, ten twelfths: its tail, at the joining of the body, two twelfths and a half: the tip of the tail one twelfth the length of the tail one inch and three twelfths: the aperture of the eye two twelfths, but this varies, apparently according to the impression of light. The cerastes has sixteen small, immoveable teeth, hollow, crooked, inwards, and of a remarkably fine polish, white in colour, inclining to blueish; near one fourth of the bottom is strongly fixed in the upper jaw, and folds back like a clasp knife, the point inclining inwards, and the greatest part of the tooth is covered with a green, soft membrane, not drawn tight, but as it were wrinkled over it; immediately above this is a slit along the back of the tooth, which ends nearly in the middle of it, where the tooth curves inwardly. From this aperture I apprehend that it sheds its poison, not from the point, where, with the best glasses, I could never perceive an aperture, so that the tooth is not a tube, but hollow only half way; the point being for making the incision, and by its pressure occasioning the venom in the bag at the bottom of the fang, to rise in the tooth, and spill itself through the slit into the wound. By this flat position of the tooth along the jaw, and its being defended by the mem

brane, it eats in perfect safety; for the tooth cannot press the bag of poison at the root while it lies in this position, nor can it rise in the tube to spill itself, nor can the tooth make any wound, so as to receive it; but the animal is supposed to eat but seldom, or only when it is with young. This viper has only one row of teeth; none but the canine are noxious. The poison is very copious for so small a creature, it is fully as large as a drop of laudanum dropt from a vial by a careful hand. Viewed through a glass, it appears not perfectly transparent or pellucid. I should imagine it hath other reservoirs than the bag under the tooth, for I compelled it to scratch eighteen pigeons upon the thigh as quickly as possible, and they all died nearly in the same interval of time; but I confess the danger attending the dissection of the head of this creature made me so cautious, that any observation I should make upon these parts would be less to be depended upon.

"People have doubted whether or not this yellow liquor is the poison, and the reason has been, that animals who had tasted it, did not die as when bitten, but this reason does not hold good in modern physics. We know why the saliva of a mad dog has been given to animals, and has not affected them; and a German physician was bold enough to distil the pus or putrid matter flowing from the ulcer of a person infected by the plague, and taste it af terwards, without bad consequences; so that it is clear the poison has no activity till through some sore or wound it is admitted into the circulation. Again, the tooth itself, divested of that poison, has as little effect. The viper deprived of his canine teeth, an operation very easily performed, bites, without any fatal consequence, with the others; and many instances there have been of mad dogs having bit people cloathed in coarse woollen stuff, which had so far cleaned the teeth of the saliva in passing through it, as not to have left the smallest inflammation after the wound.

"The cerastes is mentioned by name in Lucan, and without warranting the separate existence of any of the rest, I can see several that are but the cerastes under another term: the thebanus ophites, the ammodytes, the torrida dipsas, and the prester, all of them are but this viper, described from the form of its parts or colours*. Cato must have been marching in the night when he met this army of serpents: the cerastes hides itself all day in holes in the sand, where it lives in contiguous and similar houses to those

Luc. lib. 9.