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animals must do have confiderable ing of its prey. From the mode of progreffive motion; and this reafoning progreflive motion, they have not the we may apply to birds; for those which connection between the head and body foar very high have the greateft pro- that is called the neck, as that would greffive motion. have produced an inequality inconve nient to progreffive motion.

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

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 furface. This form of head increases the furface of contact to the fame volume of water which it removes, leffens the preffure, and is better calculated to bear the resistance of the water thro' which the animal is to pafs; proba bly, on this account, the head is larger than in quadrupeds, having more the proportion obferved in fifh, the fwelling out laterally at the articulation of the lower jaw: this may probably be, 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 fomewhat fimilar to the Swallow, Goat-fucker, Bat, &c.; which may alfo be accounted for, from their catching their food in the fame manner as fish; and this is rendered ftill more probable, fince the form of the mouth varies according as they have or have not teeth. There is, however, in the Whale tribe more variety in the form of the head than of any other part, as in the Whalebone, Bottle-nofe, and Spermaceti Whales; though in this laft it appears to owe its thape, in fome fort, to the vast quantity of fpermaceti lodged there, and not to be formed merely for the catch

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The projecting part, or tail, contains the power that produces progref, five motion, and moves the broad termination, the motion of which is fimilar to that of an oar in fculling a boat; it fuperfedes the neceflity of pofterior extremities, and allows of the proper fhape for fwimming: that the form may be preferved as much as poffible, we find that all the projecting parts, found in land animals of the fame clafs, are either entirely wanting, as the external ear; are placed internally, as the tefticles; or are fpread a long under the skin, as the udder.

The tail is flattened horizontally, which is contrary to that of fish, this pofition of tail giving the direction to the animal in the progreffive motion of the body. I fhall not pursue this circumftance further than to apply it to thofe 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 fmall, varying however in fize, and feem to ferve as a kind of oars,

To afcertain the ufe of the fin on the back is probably not fo eafy, as the large Whalebone and Spermaceti Whales have it not; one fhould otherwife conceive it intended to preferve the animal from turning.

I believe, like moft animals, they are of a lighter colour on their belly

than

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than on their back in fome they are entirely white on the belly; and this white colour begins by a regular determined line, as in the Grampus, Piked Whale, &c. in others, the white on the belly is gradually faded into the dark colour of the back, as in the Porpoife. I have been informed, that fome of them are pied upwards and downards, or have the divifions of colour in a contrary direction.

The element in which they live renders certain parts which are of importance in other animals ufelefs in them, gives to fome parts a different action, and renders others of lefs ac

count.

The puncta lachrymalia with the appendages, as the fac and duc, are in them unneceffary; and the fecretion from the lachrymal gland is not water, but mucus, as it alfo is in the Turtle; and we may fuppofe only in fmall quantity, the gland itself being finall.

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

The tongue is flat, and but little projecting, as they neither have voice, or require much action of this part, in applying the food between the teeth for the purpofe of maftication, or deglutition, being nearly fimilar to fish in this refpect, as well as in their progreffive motion.

In fome particulars they differ as much from one another as any two genera of quadrupeds I am acquaint

ed with.

The larynx, fize of trachea, and Bumber of ribs, differ exceedingly. The cæcum is only found in fome of them. The teeth in fome are want ing. The blow-holes are two in number in many, in others only one. The whalebone and fpermaceti are peculiar To particular genera: all which conftitute great variations. In other refpects we find an uniformity, which would appear to be independent of

their living and moving only in the water, as in the ftomach, liver, parts of generation of both fexes, and in the kidneys: in these last, however, I be lieve it depends in fome degree upon their fituation, although it is extended to other animals, the caufe of which I do not understand.

All animals have, I believe, a fmell peculiar to themselves: how far this is connected with the other diftinctions; I do not know, our organs not being able to diftinguifh with fufficient ac curacy.

The fmell of animals of this tribė is the fame with that of the Seal, but not fo ftrong; a kind of four smell, which the Seal has while alive; the oil has the fame fmell with that of the falmon, herring, fprat, &c.

The obfervations refpecting the weight of the flesh of animals that fwim, which I publifhed in my obfer. vations on the economy of certain parts of animals, are applicable to thefe alfo; for the flesh in this tribe is ra ther heavier than beef; two portions of mufcle of the fame fhape, one from the pfoas muscle of the whale, the other of an ox, when weighed in air, were both exacly 502 grains; but, weighed in water, the portion of the whale was four grains heavier than the other. It is probable, therefore, that the neceffary equilibrium between the water and the animal is produced by the oil, in addition to which the principal action of the tail is fuch as tends either to raise them, or keep them fufpended in the water, according to the degree 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 neceflary opportunity of breathing, and elevates them in the water; for every motion of the tail tends, as I faid be fore, to raise the animal: and that this may be effected, the greatest motion of the tail is downwards, those muscles being very large, making two ridges

in the abdomen; this motion of the tail raifes the anterior extremity, which always tends to keep the body fufpended in the water.

An immenfe head, a fmall neck, few ribs, and in many a fhort fternum, and no pelvis, with a long fpine, terminating in a point, conftitute the keleton of the whale.

The two fins are analogcus to the anterior extremities of the quadruped, and are alfo fomewhat fimilar in conftruction. A fin is compofed of a scapula, os humeri, ulna, radius, carpus, and metacarpus, in which laft may be included the fingers, becaufe the number of bones are those which might be called Fingers, although they are not feparated, but included in one general covering with the metacarpus. The flesh or mufcles of this order of animals is red, refembling that of moft quadrupeds, perhaps more like that of the bull or horse than any other animal: fome of it is very firm; and about the breaft and belly it is mixed with tendon.

Their mufcles, a very fhort time after death, lofe their fibrous ftructure, become as uniform in texture as clay or dough, and even fofter. This change is not from putrefaction, as they continue to be free from any offenfive fmell, and is most remarkable in the pfoæ muscles, and thofe of the back.

The fat of this order of animals, except the spermaceti, is what we generally term Oil. It does not coagulate in our atmosphere, and is proba bly the most fluid of animal fats. It is found principally on the outfide of the mufcles, immediately under the fkin, and is in confiderable quantity. It is inclosed in a reticular membrane, apparently compofed of fibres paffing in all directions, which feem to confine its extent, allowing it little or no motion on itself, the whole, when diftended, forming almost a folid body.

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

What is called Spermaceti is found every where in the body in fmall quantity, mixed with the common fat of the animal, bearing a very small proportion to the other fat. In the head it is the reverfe, for there the quantity of fpermaceti is large when compared 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; these are fituated along its upper and lower part: between them pafs the noftrils, and a vaft number of tendons, going to the nofe and different parts of the head.

The pureft fpermaceti lies above the noftril, all along the upper part of the head, immediately under the skin, and common adipose membrane.

This fpermaceti, when extracted cold, has a good deal the appearance of the internal ftructure of a water melon, and is found in rather folid lumps.

The fpermaceti mixes readily with other oils while it is in a fluid ftate, but feparates or cryftallifes 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 almoft wholly convertible into glue, and is fold for that purpose.

Some of thefe animals catch their food by means of teeth, which are in both jaws, as the Porpoife and Grampus; in others, they are only in one jaw, as in the Spermaceti Whale; and in the large Bottle-nofe Whale, defcribed by Dale, there are only two fmall teeth in the anterior part of the lower jaw. In the Narwhale only two tulks in the G

In this order of animals, the internal fat is the leaft fluid, and is nearly VOL. VII. No 37.

fore

fore part of the upper jaw*; while in fome others there are none at all. In those which have teeth in both jaws, the number in each varies coufiderably; the fmall Bottle-nofe had fortyfix in the upper, and fifty in the lower; and in the jaws of others there are only five or fix in each.

The teeth are not divisible into different claffes, as in quadrupeds; but are all pointed teeth, and are commonly a good deal fimilar.

Some genera of this tribe have another mode of catching their food, and retaining it till fwallowed, which is by means of the fubftance called Whalebone. Of this there are two kinds known; one very large, probably from the largeft Whale yet difcovered; the other from a fmaller fpecies.

This whalebone, which is placed on the infide of the mouth, and attached to the upper jaw, is one of the most fingular circumftances belonging to this fpecies, as they have moft 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 fhall ufe as a term to exprefs what conftitutes hair, nails, claws, feathers, &c. it is wholly compofed of animal fubftance, and extremely elaftict.

Whalebone confifts of thin plates placed in feveral rows, encompaffing the outer fkirts of the upper jaw, fi milar to teeth in other animals. They ftand parallel to each other, having one edge towards the circumference of the mouth, the other towards the center or cavity. The outer row is compofed of the longest plates; and thefe are in proportion to the different diftances between the two jaws, fome being fourteen or fifteen feet long, and twelve or fifteen inches broad; but towards

the arterior and posterior part of the mouth, thy are very short: they rife for half a foot or more nearly of equal breadths, and afterwards fhelve off from their inner fide until they come near to a point at the outer: the exterior of the inner rows are the longeft, correfponding to the termination of the declivity of the outer, and become fhorter and fhorter till they hardly rife above the gum. In all of them, the termination is in a kind of hair, as if the plate was split into innumerable fmall parts, the exterior being the longest and strongest.

The ufe of the whalebone, I fhould believe, is principally for the retention of the food till fwallowed; and do fuppofe the fifh they catch are small, when compared with the fize of the

mouth.

I never found any air in the intef tines of this tribe; nor indeed in any of the aquatic animals.

The food of the whole of this tribe, I believe, is fifh: probably each may have a particular kind, of which it is fondeft, yet does not refufe a variety. In the ftomach of the large Bottlenofe I found the beaks of fome hundreds of Cuttle-fifh. In the Grampus I found the tail of a Porpoise ; fo that they eat their own genus. In the ftomach of the Piked Whale I found the bones of different fish, but particularly thofe of the Dog-fifh. From the fize of the oefophagus we may conclude, that they do not fwallow fifh fo large in proportion to their fize as many fifh do, that we have reafon to believe take their food in the fame way for fish often attempt to fwallow what is larger than their stomachs can at one time contain, and part remains in the cefophagus till the reft is digefted.

The blood of animals of this order

is,

I call these Tusks, to diftinguish them from common teeth. A tusk is the kind of tooth which has no bounds fet to its growth, excepting by abrasion, as the tufk of the Elephant, Boar, Sea-horfe, Manatee, &c.

From this it muft appear, that the term bone is an improper one.

is, I believe, fimilar to that of quadrupeds; but I have an idea, that the red globules are in larger proportion. I will not pretend to determine how far this may affift in keeping up the animal heat; but as these animals may be faid to live in a very cold climate or atmosphere, and fuch as readily carries off heat from the body, they may want fome help of this kind.

It is certain that the quantity of blood in this tribe and in the feal is comparatively larger 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 feal, is probably larger in proportion to their fize than in the quadruped, as alfo the blood-veffels, more efpecially

the veins.

In our examination of particular parts, the fize of which is generally regulated by that of the whole animal, if we have only been accustomed to fee them in those which are fmall or middle-fized, we behold them with aftonishment in animals fo 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 meafuring a foot in diameter. When we confider thefe as applied to the circulation, and figure to ourselves, that probably ten or fifteen gallons of blood are thrown out at one troke, and moved with an immenfe velocity through a tube of a foot diameter, the whole idea fills the mind with wonder.

The membranous portion of the pofterior noftrils 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 fome continued double through the anterior foft parts, opening by two orifices, as in the Piked Whale; but in others it unites again in the mem

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

In the whole of this tribe, the fituation of the opening on the upper furface of the head is well adapted for this purpose, being the first part that comes to the furface of the water in the natural progreffive motion of the animal; therefore it is to be confidered principally as a respiratory organ, and where it contains the organ of fmell, that is only fecondary,

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

How the male and female copulate I do not know, but it is alledged that their pofition in the water is e red at that time, which I can readily fuppofe may be true; for otherwife, if the connection is long, it would interfere with the act of refpiration, as in any other pofition the upper furface of the heads of both could not be at the furface of the water at the fame time. However, as in the parts of generation they most resemble thofe of the ruminating kind, it is poffible they may likewife refemble them in the duration of the act of copulation, for I believe all the ruminants are quick in this act.

Of their uterine geftation 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 feemed to be the cafe with the Bottle-nofe Whale caught near Berkeley, which had been seen for fome days with one young following it, and they, were 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 furgeon at Sodbury, was rich like cow's milk to which cream had been added.

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