174 



MAMMALIA. 



cut we have given a representation, both of the form 

 of the muscles in the leg of the lion, which perform 

 the grand or general movements of that organ, and 

 also of the particular formation of the toe of the lion, 

 in consequence of which the claw when not in use is 

 so perfectly protected from injury, and yet enabled 

 to act so readily and so powerfully when the wants 

 of the animal require it. 



The one of these figures represents, as well as it 

 can be done in a small sketch, the various muscles, 

 together with their tendons and ligaments, which 

 work the claws of the lion's fore paw ; and this paw, 

 although the hind one is also powerful, is by far the 

 most efficient in the economy of the animal. 



Upon examining that portion of the cut which 

 represents the full length of the claws (though the 

 integuments are in great part dissected away), and the 

 wrist and greater part of the form arm, it will be 

 seen that in the form and arrangement of the muscles 

 there is no inconsiderable resemblance to the human 

 arm. We might have been prepared to expect this 

 from the analogy ; because, though the paw of the 

 lion is not only a better walking instrument than the 

 human hand, but is really a very efficient instrument 

 for this purpose, yet walking is far from being its 

 only or even its chief operation. The paw of the lion 

 no doubt conveys him to the place where his prey is 

 to be met with, and he runs moderately fast, and 

 struts and stalks on his slow march with all the ma- 

 jesty of a Hercules ; but notwithstanding this, the 

 muscies on the fore arm of the lion do not take a 

 leading part, or even very powerfully assist in the 

 walking motion. Their purpose is the working of 

 the paw, the extensors on the upper part and the 

 flexures on the under, just as in the human arm. 

 Those great muscles, as will be seen in the figure, 

 have all their tendons bound round with a very firm 

 ligament, which forms a separate pulley for each, and 

 they have a farther tendinous pulley between that and 

 the claws. One part of the action of the paw is 

 simply striking, much in the same way as the human 

 arm strikes ; and as the lion's blow is always what 

 we call a back-handed one, it is sufficient to fell a 

 pretty strong animal to the ground, or even to break 

 its bones. It indeed tells with much greater propor- 

 tional effect than the stroke of the human arm ; for 

 the lion has only a partial clavicle near the shoulder 

 end, which is embedded in muscle, and terminates in 

 cartilage, and therefore both in the lion's blow and in 

 his pace the scapular comes partially in as a lever of 

 motion , and in the direction of the mesial plane the 

 paw of the lion strikes with three articulations; whereas, 

 unless the weight of the body is delivered along with 

 the blow, the human arm strikes only with two. There 

 are some other advantages ; the bone is of more solid 

 substance than any other bone in the mammalia ; and 

 the system of muscles is remarkably strong all the 

 way to the shoulder, at which place the mane of the 

 lion preserves them from changes of temperature, and 

 thus the first motion of the limb is, in proportion to 

 its extent, remarkably free ; and thus great velocity, 

 as well as great weight and strength of matter, are 

 given to this general motion of the limb. 



It is only iu so far as the muscular structure of the 

 fore arm is concerned that there is the remaikable 

 coincidence between the lion and man to which we 

 have alluded ; for though there is a similarity between 

 the action of the lion's paw in clutching his prey 

 and that of the human hand in grasping, the paw is 



very limited in the kinds of action of which it is capa- 

 ble, as compared with a hand. It will be seen from 

 the position of the pulleys through which the tendons 

 of the flexor muscles (and they are the ones prin- 

 cipally shown in the cut), that the general action 

 in compressing the paw is a drawing of all the claws 

 in the direction of the centre of the foot, by which 

 means, though there is no reversible thumb, the 

 claws, when they take effect, are capable of holding 

 on against each other with the firmness of a crab. Great 

 care is also taken that this apparatus shall suH'er no 

 injury from the weight of the animal, either in walking 

 or in straining, while the foot holds on in rending the 

 prey. The balls of the toes which answer to the 

 under sides of the knuckles, or balls of the fingers in 

 the human subject, are amply provided with pads so 

 large, so thick, and so elastic, that though the animal 

 alights on them upon hard ground from his most 

 vigorous and prolonged leap, the acting parts of the 

 under side of the foot can sustain no injury. 



The portion of the mechanism, however, which is 

 most worthy of attention as illustrative of the struc- 

 ture of most of the carnivorous animals, is the claw 

 itself, and the machinery by which it is worked. It 

 is necessary to keep in mind that, in the human hand, 

 in the lion's paw, and in the foot of every animal 

 which has much motion of the toes, there are many 

 muscles besides those which are situated on the fore 

 arm. These last are as it were the large and rude 

 pans of the machinery, fitted for strength of motion, 

 but not for delicacy, and all the finer operations of 

 the organ are left to the others. These secondary 

 and smaller muscles which perform the delicate ope- 

 rations affect all the bones of the organ, the carpal 

 bones, the bones of the metacarpus, and the phalan- 

 ges of the fingers. In the human subject these muscles 

 are exceedingly numerous, because of the motions, 

 which, independently of the motions of the arm, the 

 hand is capable of performing. The last two joints 

 of the fingers have not, indeed, much lateral motion, 

 for that would render them unsteady, but they have 

 all a considerable degree of such motion on their 

 metacarpal joints; while the thumb, different from 

 the corresponding in even the handed animals, has 

 such a motion on two joints, and is steady laterally 

 only upon the last one. In consequence of this 

 number of small muscles, and of the number or pecu- 

 liarity of the bones to which they are applied, the 

 actions of the hand are altogether beyond the power 

 of numbers to express, and those smaller muscles 

 become delicate in their action as they diminish in 

 size, so that if they are not overpowered by the more 

 habitual action of the larger muscles, the operations 

 which the hand can perform are as nice as they are 

 numerous. There is, however, this peculiarity in the 

 hands as well as in every organ and every animal 

 with which we are acquainted, that when one peculiar 

 set of muscles is frequently and strongly employed, 

 the energy of the organ or of the animal is habituated 

 to that particular set of muscles, and all the rest be- 

 come less capable of performing their function, than if 

 the whole were equally exercised. The action of the 

 lion's paw is a very limited action as compared with 

 that of the human hand ; but in proportion as it is 

 limited, it is more energetic in all that it is capable 

 of doing. This is in accordance with that general law 

 of the animal economy to which we have had occasion 

 so often to allude ; and it is gratifying in the highest 

 degree to find that a few very simple general prin- 



