MAMMALIA. 



183 



The general characters which run through the 

 whole order are, the toes of the foot well developed ; 

 but without a thumb opposible to the toes ; and they 

 have all three sorts of teeth incisors, canine?, and 

 cheek teeth ; the second in general so produced 

 that they act not sufficiently in wounding and killing, 

 and the third variously formed according to the na- 

 ture of the prevailing food of the animal. They all 

 live, in part at least, upon animal substances ; and 

 those which do this the most exclusively have their 

 cheek teeth with the most trenchant or hatchet-like 

 edges, so that they can readily cut asunder the flesh 

 of animals, when it is in the recent state, and can- 

 not readily be divided by a simple bruise. Those 

 which have some of the cheek teeth at least with 

 turbercles on the crowns, live more or less upon 

 vegetable matter, though upon matter of a more suc- 

 culent and nourishing description than that which 

 forms the food of the genuine and habitual vegetable 

 feeders. Those again which have the cheek teeth 

 beset with little sharp points on the crowns, feed 

 more exclusively upon insects, and other small in- 

 vertebrated animals ; though there are some even 

 of these last which are especially ravenous in the 

 true carnivorous way, until they become canibals, 

 after a violent struggle for the mastery. Even those 

 which occasionally feed on vegetables have no lateral 

 or grinding motion of the jaws, so that they have no 

 means of reducing fibrous vegetable matter to any- 

 thing like a pulp, so as to prepare it for the single and 

 simple stomach with which they are furnished. The 

 quadrumana, as well as man, have a motion of this 

 kind, so that they can grind the food by rolling it 

 between the cheek teeth : whereas the carnassiers 

 can simply close their jaws upon it, without any 

 means of dividing it. This reduction of the action 

 of the jaws to one plane, concentrates it more than 

 in those animals which grind their food ; and thus 

 their direct bite is more keen and steady in proportion 

 to the degree of muscular energy exercised in pro- 

 ducing it. 



The brain in these animals is better developed 

 than in any of the orders which follow them ; but 

 still the cerebrum is without the third lobe, and it 

 does not form a duplicature over the cerebellum, as is 

 the case in man and in the quadrumana. There is 

 also no septum of bone between the temporal fossa 

 and the orbit of the eye. Their skull is also much 

 more compressed in proportion to its length than 

 that of the quadrumana, even such of them as have 

 the muzzle produced by a lengthening of the bones 

 of the face ; but though these forms of organisation 

 are different from those of the quadrumana, we must 

 not thence conclude that the animals themselves 

 possess less animal sagacity, or have fewer resources. 

 The want of the third lobe in the brain appears to 

 have really more connexion with the absence of the 

 power of grasping, than with that of animal sagacity ; 

 for some of the carnassiers are exceedingly cunning in 

 a state of nature, and others are capable of more 

 education than almost any other animal, and can be 

 made to perform work, and valuable work, which 

 could not be performed by any ape, and not even by 

 man himself. A dog will find his master when no 

 human inquirer can ; and a blood hound will track 

 that upon the slot of which he is sent, with a cer- 

 tainty and a perseverance which is perfectly inexpli- 

 cable upon the principle that regulates the animal 

 functions of man, and even by mind itself. 



The other differences between the carnassiers and 

 the quadrumana, are not to be regarded as fallings 

 oh" of development in the latter, any more than the 

 difference in the brain to which we have now ad- 

 verted. The absence of septa, or partitions of bones 

 between the temporal fossa? and the sockets of the 

 eyes, gives the animals an increase of power, instead 

 of a deficiency. By this means, they are enabled to 

 have the eyes placed more laterally, so as to com- 

 mand a more extensive horizon without turning the 

 head, and the absence of the partition and the eleva- 

 tion of the arch gives more room for the origin of 

 those powerful muscles which move the jaws. Gene- 

 rally speaking they have clavicles more or less per- 

 fect; and they have a rolling motion in the elbow 

 joint, so that the extremity of the fore foot com- 

 mands an extent of motion in the cross direction, as 

 well as in the backward and forward one. They are 

 also less loaded with the organs of digestion than 

 even the quadrumana ; for the food being in most 

 instances of a much more nourishing nature, they 

 require less of it, and do not retain the parts unfit 

 for assimilation so long within the cavities of the 

 body. Simple as this last peculiarity may seem, it is 

 attended with considerable advantages to the animals. 

 They have to seize their food with more exertion 

 than the other mammalia, as they have generally 

 speaking to catch and kill before they can eat. 

 They, therefore, require that a larger portion of their 

 weight should be applied to external action, and a 

 less portion to digestion ; and it is a beautiful provi- 

 sion of nature, that the food of these, and indeed of 

 all animals, should be nourishing in proportion to the 

 quantity of muscular exertion which the animal must 

 exercise in order to arrive at it. The nourishment, 

 and the capacity of undergoing the exertion, also har- 

 monise with each other. In proportion as the mus- 

 cular system of an animal is exerted, a supply of 

 arterial blood is required. This supply cannot be 

 obtained in a wholesome state unless there is some 

 chyle to mix with the returning blood ere it is sent 

 through the heart to the lungs in order to undergo 

 the purifying influence of atmospheric air. This is 

 the reason why people in an extreme of hunger wax 

 faint and are incapable of muscular exertion ; and it 

 is also the reason why the derangement of the diges- 

 tive organs should have so enfeebling an effect on 

 the muscular energy of the body, or upon the spirits, 

 as we say in common language. The discovery 

 that these very simple and very general principles 

 run through the whole system of nature, is one of 

 the greatest encouragements that we have in the 

 study of natural history ; because it shows us that no 

 one subject which we can study has its instruction 

 confined entirely to itself; but that on the other 

 hand every portion of knowledge which we can ac- 

 quire, at once becomes the instrument of additional 

 knowledge which we can use with equal readiness 

 and success. 



The carnassiers, to the extent to which Cuvier 

 carries the order, and notwithstanding the differ- 

 ences which prevail among the genera and species, the 

 order is a very compact and complete one, and renders 

 a subdivision into suborders or families necessary ; and 

 some of these suborders are so numerous that they 

 admit of a farther division into groups before we 

 come to the genera. Cuvier's first sub-divisions are 

 the Cheiroptera, or bat family ; Insectivora, or those 

 which live chiefly on insects ; Cariiivora. or thote 



