cences of this kind, and the back and limbs profusely sprinkled over with them: some of the horns, and especially those about the dew-lap, were as long and as large as the natural horns of the forehead, but they were much more calcareous and brittle. A calcareous scurf, moreover, was secreted over every part of the skin, which, whenever the skin was scratched or bitten, united with the fluid that oozed forth, ramified, and divaricated into masses of small roses. At the request of the proprietor, I took an account of this extraordinary animal, and have since communicated it to the Royal Society. In all other respects it was in good health; its size was proportionate to its age, and its appetite enabled it to digest foods of every kind equally; and though, in consequence of this, its diet had been frequently varied, the propensity to a secretion of calcareous matter continued the same under every change.

It appears, therefore, very doubtful whether the animal economy be not at times capable of generating lime, as well as gelatine or albumen, out of the different materials introduced into the stomach in the form of food. Vauquelin endeavoured to decide the question by a variety of experiments upon the nature of the egg-shells of a sitting hen, and an examination into the proportion of calcareous matter contained in a given weight of shells, compared with the calcareous matter furnished by her food, and that discharged as a recrement; and, so far as these experiments go, they support the opinion of a generation of lime, and that in very considerable abundance, the weight secreted appearing to have been five times as much as that introduced into the stomach. But to determine the question incontro

vertibly requires so nice a precision in the mode of conducting such experiments, as, from a variety of circumstances, it seems almost impossible to attain.*

It is to the power which the living principle possesses, either of secreting or generating the substance of lime by its natural action, that we are indebted for all those elegant shells that enrich the cabinet of the conchologist, and seem to vie with each other in the beauty of their spots, the splendour and irridescence of their colours, and the graceful inflection of their wreaths. And it is to the power which the same principle possesses, of forming this substance by a morbid action, that we owe not only those unsightly excrescences I have just mentioned, but some of the most costly ornaments of superstition or luxury; those agate-formed bezoards, which in Spain, Portugal, and even Holland, were lately worn as amulets against contagion, and which have been let out for hire at a ducat a day, and been sold as high as three hundred guineas each; and those delicate pearls which constitute an object of desire among the fair sex of every country, and which give

additional attraction to the most finished form.

The first are usually obtained from the stomach or intestines of the goat or antelope; in the latter case being called oriental bezoards, and possessing the highest value. The most esteemed are those obtained from the stomach of that species of the oriental antelope called the gazel, to which the Persian and Arabian poets are perpetually adverting whenever they stand in need of an image to express elegance of form, fleetness of speed, or captivating *The reader, however, will do well to consult the researches of Dr. Prout on this subject. Ed.

softness of the eyes. The second are obtained from the inside of the shells of the mytilus margaritiferus and mya margaritifera, pearl-muscle and pearloyster the former, producing the largest and consequently the richest, is found most commonly on the coast of Ceylon; the latter not unfrequently on that of our own country, and was traced some centuries ago in great abundance in the river Conway in Wales. Linnæus is said to have been acquainted with a process by which he could excite at pleasure a secretion of new pearls in the pearl-oyster which he kept in his reservoirs. It is generally supposed to be a diseasedsecretion, somewhat similar to that of the stone in the human bladder.

The murex tritonis, or musical murex, is here also worth noticing. Its calcareous shell is ventricose, oblong, smooth, with rounded whorls, toothed aperture, and short beak, about fifteen inches long, white, and appearing as if covered with brown, yellow, and black scales. It inhabits India, and the South Seas, and is used by the New Zealanders, as a musical shell, and by the Africans and many nations of the east as a military horn.

Before we quit this subject, I will just observe, that it is to the same tribe we are indebted for our nacre or mother-of-pearl, which is nothing more than the innermost layers of the shell, in which the morbid works or concretions which we call pearls lie embedded; and that to the same order of shells the Indians owe their wampum or pieces of common money, which are formed of the Venus mercenaria, or clam-shell, found in a fossil state; and that our own heralds owe the scallop, ostrea maxima, that so often figures in the field of our family arms, and was

formerly worn by pilgrims on the hat or coat, in its natural state, as a mark that they had crossed the sea for the purpose of paying their devotions at the Holy Land.

From these facts and observations we cannot but behold the great importance of lime in the construction of the animal frame, the extensive use which is made of it, and the variety of purposes to which it is applied: combined in different proportions with gluten and albumen, it affords equally the means of strength and protection, produces the bones within and the shells without, the external and internal skeleton, and is discoverable in every class, order, and even genus of animals, except a very few of the soft worms and insects in their first and unfinished state.

It is hence the cerambyx, and several other tribes of insects, are able to make that shrill sound which they give forth on being taken, and which appears like a cry from the mouth, but is in reality nothing more than the friction of the chest of the insect against the upper part of its abdomen and wingshells. And it is hence, also, that the ptinus fatidicus, or death-watch, produces those measured strokes against the head or other part of a bed in the middle of the night, which are so alarming to the fearful and superstitious; but which, in truth, are nothing more than a call or signal by which the one sex is enticed to the other, and is merely produced by the insect's striking the bony or horny front of its head against the bed-post, or some other hard substance.

Having, then, taken a brief survey of the elementary nature and chemical composition of these

harder parts of the animal frame, I shall proceed to make a few remarks upon the relative powers of each, and their diversified applications amidst the different kinds of animals in which they are employed.

The BONES in their colour are usually white; but this does not hold universally, for those of the garpike (esox belone) are green; and in some varieties of the common fowl they approach to a black: Abelfazel remarks this of the fowls of Berar, and Niebuhr of those of Persepolis.

The bones of an animal, wherever they exist, are unquestionably the levers of its organs of motion: and so far the mechanical theorists are correct. In man and quadrupeds, whose habits require solidity of strength rather than flexibility of accommodation, they are hard, firm, and unpliant, and consist of gluten fully saturated with phosphate and carbonate of lime. In serpents and fishes, whose habits, on the contrary, demand flexibility of motion, they are supple and cartilaginous; the gluten is in excess, and the phosphate of lime but small in proportion to it, and in some fishes altogether deficient in the composition of their skeleton, though still traceable in their scales and several other parts. In birds, whose natural habits demand levity, the bones are skilfully hollowed out and communicate with the lungs, and instead of being filled with marrow are filled with air, so that the purpose for which the structure of birds was designed is as obvious, and as deeply marked, in the bones as in the wings, whose quills also are for the same reason left hollow, or rather are filled with air, and in many tribes communicate with the lungs as the bones do.