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•firmals must do) have considerable progressive motion ; and this reasoning we may apply to birds ; for those which soar very high have the greatest progressive motion.

Although inhabitants of the waters, they belong to the fame class as quadrupeds, breathing air, being furnished with lungs, and all-the other parts peculiar to the economy of that class, and having warm blood: for we may make this general remark, that in the different classes of animals there is never any mixture of those parts which are dlctiti.il to life, nor in their different modes of sensation.

The form of the head or anterior part of this order of animals, is commonly a cone, or an inclined plane, except in the Spermaceti Whale, in which it terminates in a blunt surface. This form of head increases the surface of contact to the same volume of water which it removes, lessens the pressure, and is better calculated to bear the resistance of the water thro' which the animal is to pass ; proba* My, on this account, the head is larger than in quadrupeds, having more the proportion observed in iiili, the swelling out laterally Vt the articulation of the lower jaw: this may probably bo. for the better catching their prey, as they have no motion of the head on the body; and this distance Between the articulations of the jaw is somewhat similar to the Swallow, Goat-sucker, Bat, &c.; which may alio be accounted for, from their catching their food in the same manner as filli; and this is rendered still more probable, since the form of the mouth varies according as they have or have not teeth. There it, however, in the Whale tribe more variety in the form -of the head than of any other part, as in the Whalebone, Bottle-nose, and Spermaceti Whales; though in this last it appears to owe its wane, in some fort, to die vast quantity of spermaceti lodged there, and ••t» be formed merely for the each

ing of its prey. From the mode of progressive motion, they have not the connection between the head and body that is called the neck, as that would have produced an inequality inconvenient to progressive motion.

The body behind the fins or shoulders diminishes gradually to the spread* ing of the tail; but the part beyond the opening of the anus is to be considered as tail, although to appearance it is a continuation of the body. The body itself is flattened laterally; and, I believe, the back is much (harper than the belly.

The projecting part, or tail, con-* tains the power that produces progress five motion, and mores the broad termination, the motion of which is similar to drat of an oar in sculling about; it supersedes the necessity of posterior extremities, and allows of tho proper shape for swimming: that the form may be preserved as much as possible, we find that all the projecting pans, found in land animals of the fame class, are either entirely wanting, as the externaL'ear; are placed internally, as the testicles ; or are spread-a% long under the Ikin, as the udder.

The tail is flattened horizontally, which is contrary to that of fish, this position of tail giving the direction to the animal in the progressive motion of the body. I shall not pursue this circumstance further than to apply it to those purposes in the animal economy for which this particular direction is intended.

The two lateral fins, which are analagous to the anterior extremities in the quadruped, are commonly small, varying however in size, and seem to serve as a kind of oars.

To ascertain the use of the Jin on the back is probably not so easy, as the large Whalebone and Spermaceti Whales have it not; one lhould otherwise conceive it intended to preserve the animal from turning.

I believe, like most animals, they are of a lighter colour sa their belly

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than on their hack: in some they are entirely white on the belly; and this white colour begins by a regular determined line, as in the Grampus, Pifced Whale, &c.: in others, the white on the belly is gradually shaded into the dark colour of the back, as in the Porpoise. I have been informed, that some of them are pied upwards and downards, or have the divisions of colour in a contrary direction.

The element in which they live renders certain parts which are of importance in other animals useless in them, gives to some parts a different action, and renders ptheis of less account.

The puncta lachrymalia with the appendages, as the sac and due, are in them unnecessary; and the secretion from the lachrymal gland is not water, but mucus, as it -also is in the Turtle; and we may suppose only in small quantity, the gland itself being small.

The urinary bladder is smaller than In quadrupeds; and indeed there is not any apparent reason why whales mould have one at all.

The tongue is flat, and but little projecting, as they neither have voice, Aor require much action of this pan, in applying the food between the teeth for the puipose of mastication, or deglutition, being nearly similar to fish in this respect, as well as in their progressive motion.

• Ir> some particulars they differ as much from one another as any two genera of quadrupeds I am acquainted with.

The larynx, size of trachea, and •umber of ribs, differ exceedingly. The cæcum is only found in some of them. The teeth in some are wanting. The blow-holes are two in number in many, in others only one. The whalebone and spermaceti are peculiar to particular genera: all which constitute great variations. In other respects we find an uniformity, which would appear to be independent of

their living and moving only in tfifc water, as in the stomach, fiver, partfc osgeneration of both sexes, and in the: kidneys: in these last, howc\ er, I be* Iieve it depends in some degree upoa their situation, although it is extended to other animals, the cause of whicR I do not understand.

AU animals have, I believe, a smell peculiar to themselves : how fir this i» connected with the other distinctions* I do not know, our organs not being able to distinguish with sufficient ac* curacy.

The smell of animals of this tribes is the fame with that of the Seal, but not so strong; a kind of four smell, which the Seal has while alive; the! oil has the fame smell with that of the salmon, herring, sprat, &c.

The observations respecting the weight of the Hem of animals that swim, which I published in my observations on the economy of certain parts of animals, are applicable to these also; for the flesh in this tribe is ra-« ther heavier than beef; two portions of muscle of the same shape, one frorri the psoas muscle of the whale, the other of an ox, when weighed in air,' were both exactly 502 grains 5 but, weighed in water, the portion of the! whale was four grains heavier than the! other. It is probable, therefore, thats the necessary equilibrium between the water and the animal is produced by the oil, in addition to which the principal action of the tail is such as tends* either to raise them, or keep then* suspended in the water, according tof the decree of force with which it acts.

From the tail being horizontal, the? motion of the animal, when impelled by it, is up and down: two advan-> tages are gained by this, it gives the* necessary opportunity of breathing, and elevates them in the water; for every' motion of the tail tends, as I said before, to raise the animal: and that this* may be effected, the greatest motion of the tail is downwards, those muscles? bging yery large, making two ridge* » the abdomen; this motion of the tail raises the anterior eX'remity, which a)w.iys tends to keep the body suspended in the water.

Observations on the Slrttftitre and Economy osWhAes.

An immense head, a (mall neek, few ribs, and in many a short (termini, and no pelvis, with a long spine, terminating in a point, constitute the skeleton of the whale.

The two fins are analogous to the anterior extremities of the quadruped, and are also somewhat similar in construction. A fin is composed of a fcapula, os humeri, ulna, radius, carpus, and metacarpus, in which lad may be included the fingers, because the nnmber of bones are those which might be called Fingers, although they are not separated, but included in one genera! covering with the metacarpus.

The flesh or muscles of this order of animals is red, resembling that of molt qnadrupeds, perhaps more like that of the bull or horse than any other animal: some os it is very firm; and about the breast and belly it is mixed with tendon.

Their muscles, a very fliort time after death, lose their fibrous structure, become as uniform in texture as clay or dough, and even softer. This change is not from putrefaction, as they continue to be free from any offensive smell, and is molt remarkable in the psox muscles, and those of the back.

The fat of this order of animals, except the sj>ermaceti, is what we generally term Oil. It does not coagulate in our atmosphere, and is probably the most fluid of animal fats. It is sound principally on the outside of the muscles, immediately under the skin, and is in considerable quantity. It is inclosed in a reticular membrane, apparently composed of fibres pasting ki all directions, which seem to confine its extent, allowing it little or no motion on itself the whole, when distended, forming almost a solid body.

In this order of animals, the internal fat is the. least fluid, and is nearlv

Vol. VII. No 37. g

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of the consistence of hog's lard ; the external is the common train oil; but the Spermaceti Whale differs from every other animal I have examined, having die two kinds of fat just mentioned, and another, which is totally different, called Spermaceti, of which I shall give a particular account.

What is called Spermaceti is found every where in the body in small quantity, mixed with the common fat of the animal, bearing a very small proportion to the other fat. In the head it is die reverse, for there the quantity of spermaceti is large when comjxired to that of the oil, although they are mixed, as in the other parts of the body.

There are two places in the head where this oil lies s diese are situated along its upper and lower part: be?tween them pass the nostrils, and a vast number of tendons, going to the nose and different parts of the head.

The purest spermaceti lies above the nostril, all along the upper part of the head, Immediately under the skin, and common adipose membrane.

This sj>erm»ceti, when extracted cold, has a good deal the appearance of the internal structure of a water melon, and is found in rather solid lumps.

The spermaceti mixes readily widi other oils while it is in a fluid state, but separates or crystallises whenever it is cooled to a certain degree.

What remains of the blubber, or external fat of the whale, after all the; oil is extracted, retains a good deal of its form, is almost wholly convertible into glue, and is sold for that purpose.

Some of these animals catch their food by means of teeth, which are in both jaws, as the Porpoise and Grampus i in others, diey are only in one jaw, as in the Spermaceti Whale; and in the large Borde-nose Whale, described by Dale, there are only two small teeth in the anterior part of the lower jaw. In.the Narwhale only two tufks.in the

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fore part of the upper jaw * ; while in the anterior and' posterior part of tire some others there are none at all. In those which have teeth in both jaws, the number in each varies considerably; the small Bottle-nose had fortysix in the upper, and fifty in the lower; and in the jaws of others there are only five or six in each.

The teeth are not divisible into different classes, as in quadrupeds; but arc all pointed teeth, aud are commonly a good deal similar.

Some genera of this tribe have another mode of catching their food, and retaining it till swallowed, which is by means of the substance called Whalebone. Of this there are two kinds known ; one very large, proiably from the' largest Whale yet discovered; the other from a smaller species.

This whalebone, which is placed on jthe inside of the mouth, and attached to the upper jaw, is one of the most singular cireumstances belonging to this species, as they have most other parts in common with quadrupeds. It is a substance, I believe, peculiar to .the whale, and of the fame nature as horn, which I shall use as a term to

mouth, thy are very stiort: they rife for half a foot or more nearly of equal breadths, and afterwards shelve off from their inner side until they come near to a point at the outer: the exterior of the inner rows* are the longest, corresponding to the termination of the dtclivity of the outer, and become shorter and shorter till they hardly rise above the gum. In all of them, the termination is in a kind of hair, as if the plate was split into innumerable small parts, the exterior being the longest and strongest.

The use of the whalebone, I should believe, is principally for the retention of the food till swallowed ; and do suppose the fish they catch are small, when compared with the size of the mouth.

I never sound any air in the intestines of this tribe ; nor indeed in any of the aquatic animals.

1'he food of the whole of this tribe, I believe, is fish: probably each may have a particular kind, of which it is fondest, yet does not refuse a variety. In the stomach of the large Bottlenose I fonnd the beaks of some hun

express what .constitutes hair, nails, dreds of Cuttle-fish. In the Grani.claws, feathers, &c. it is wholly com- pus I sound the tail of a Porpoise j posed of animal substance, and ex- ib that they eat their own genus. In iremely elastics. the stomach of the Piked Whale I Whalebone consists of thin plates sound the bones of different fish, but placed in several rows, encompassing particularly those of the Dog-fish. the outer skirts of the upper jaw, si- From the size of the œsophagus wa inilar to teeth in other animals. They may conclude, that they do not swalsfand parallel to each other, having one low sish so large in proportion to their edge towards the circumference of the size as many fish do, that we hare mouth, the other towards the center or reason to believe take their food in the .cavity. The carter row is composed of same way: for fish often attempt lathe longest plates ; and these are in pro- swallow wnat is larger than their stoportion to the different distances be- machs can at one time contain, and tween the two jaws, some being sour- part remains in the œsophagus till tke teen or fifteen sect long, and twelve rest is digested. or fifteen inches broad; but towards The blood of animals of this order

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* I call these Tusks, to distinguish them from common teeth. A tuft is the kind ef tooth which ha» no bounds set to its growth, excepting by abrasion,, as the :use of the Elephant, Boar, Sea-horse, Manatee, &c.

\ From this it must appear, that the term bom is an improper one.

Observations on the StruRure and Economy ^"Whales.

15, I believe, similar to that of quadrupeds; but I have an idea, that the red globules are in larger proportion. I will not pretend to determine how fir this may asiist in keeping up the animal heat; but as these animals may be said to live in a very cold climate or atmosphere, and such as readily carries off heat from the body, they may want some help of this kind. . It is certain that the quantity of blood in this tribe and in the seal is comparatively Lirger than in the quadruped, and therefore probably amounts to more than that of any other known animal.

The heart in this tribe, and in the leal, is probably larger in proportion to their size than in the quadruped, as also the blood-vefTels, more especially the veins.

In our examination of partic«'a'r pant, die size of which is generally regulated by that of the whole animal, if we have only been accustomed to fee them in those which are small or middle-sized, we behold them with astonishment in animals so far exceeding the common bulk, as the Whale. Thus the heart and aorta of the Spermaceti Whale appeared prodigious, being too large to be contained in a wide tub, the aorta measuring a foot in diameter. When we consider these as applied to the circulation, and figure to ourselves, that probably ten or fifteen gallons of blood are thrown out at one stroke, and moved with an immense velocity through a tube of a foot diameter, the whole idea sills the mind with wonder.

The membranous portion of the posterior nostrils is one canal; but when in the bony' part, in most of them, it is divided into two; the'Spermaceti Whale, however, is an exception. In those which have it divided, it is in some continued double through the anterior soft parts, opening by two orifices, as in the Piked Whale; but ■a others it unites again in the mem

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branous part, making externally only one orifice, as in the Porpoise, Grampus, and Bottle-nose.

In the whole of this tribe, the situation of the opening on the upper surface of the head is well adapted for this purpose, being the first part that comes to the surface of the water in the natural progressive motion of the animal ; therefore it is to be considered principally as a respiratory organ, and where it contains the organ of smell, that is only secondary.

The parts of generation in both sexes of this order of animals come nearer in form to those of the ruminating than of any others.

How the male and female copulate I do not know, but it is alledged; that their position in the water is e» rect at that time, which I can readily suppose may be true; for otherwise, if the connection is long, it would interfere with the act of respiration, as: in any other position the upper surface of the heads of both could not be at the surface of the water at the same time. However, as in the parts of generation' they most resemble those of the ruminating kind, it is possible they may likewise resemble them in the? duration of the act of copulation, for I believe all the ruminants are quick, in this act.

Of their uterine gestation I as yet know nothing; but it is very probable that they have only a single young one at a time, there being only two nipples. This seemed to be die case with the Bottle-nose Whale caught near Berkeley, which had been seen for some days with one young following it, and theywere both caught together.

The milk is probably very rich; for in that caught near Berkeley with its young one, the milk, which was tasted by Mr Jenner, and Mr Ludlow surgeon at Sodbury, was rich like cow's milk to which cream had bcea added.

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