A R M A D I L L O. 



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ryes from perpendicular light, but not to cover either 

 them or the ears. It is composed of a number of 

 tubercttlated pieces, but so closely united together as 

 to form one imnloveable covering- of very consider 

 able firmness and strength. From the edges of this 

 there generally proceed two rows of hard tubercles, 

 vvhich pass under the eyes, become gradually smaller, 

 and terminate on the cheeks. 



The plate or buckler on the neck and shoulders 

 is much larger, and descends laterally so much as to 

 conceal the greater part of the fore legs except the 

 feet. 



The intermediate plates and the plate on the 

 crupper descend also far down laterally, so that the 

 la>t in a great measure conceals the hind legs ; and 

 thus the whole animal appears " thatched," so to 

 express it, with transverse bands of shell or crust, 

 which are so thick, firm and hard as to be a perfect 

 defence against the attacks of almost any animal. 



The tail also has its armour, which consists of a 

 greater or smaller number of rings, not perhaps abso- 

 lutely united into a solid, but still usually admitting 

 of little or no motion in that organ. 



From this external covering of the armadillo it is 

 the least flexible of all the mammalia ; and when it 

 turns, it turns h'ke a block upon legs, without any 

 perceptible bending of the body even at the junctions 

 of the intermediate plates. The head is capable 

 of little elevation, so that, in a lateral or upward 

 direction, the animal is less capable of motion than a 

 tortoise. In the remaining direction, or downwards, 

 the motion is more free, as some species can roll 

 themselves partially, and one of them completely 

 into a ball. 



Though the uses of this most singular covering, in 

 the economy of these curious animals, are little 

 understood, yet they must be important, as the 

 organisation, especially that of the spinal column, has 

 reference to it. With respect to their internal struc- 

 ture, however, it is very difficult to speak generally, 

 as there are differences in the species, sufficient 

 almost to call for divisions into different genera ; and 

 all the species have not been dissected with equal 

 care. The point, of resistance to the general action 

 of the spine, and indeed to that of the whole animal, 

 appears to be the sacral or hinder extremity. The 

 whole thence to the muzzle pushes forward as a stiff 

 and nearly inflexible column, sustained partly on the 

 spine itself, and partly by the armour. 



On the frontal bone there are two elevated pro- 

 cesses, one object of which is evidently to support 

 the helmet or plate which covers the head ; and 

 these differ with the form of the head and relative 

 size of the helmet in the different species. The 

 number of vertebrae in the neck is seven, as in all 

 mammalia; but their structure is very different from 

 that of animals which have free motion in that part 

 of their bodies : very remarkably different from the 

 neck of the tortoise, which, though an animal of a 

 different class, is very apt to occur to one's memory 

 when examining an armadillo. The short neck of 

 that animal has its vertebrae so articulated, as to 

 admit of more motion within a limited compass, than 

 perhaps any other animal structure. The neck of 

 the armadillo is the very reverse : it has little motion 

 in any of the joints, and some of the vertebrae, espe- 

 cially the third and fourth, which being the middle 

 ones, necessarily give stiffness to the whole neck, are 

 anchylosed or united together. In this respect the 



neck of those animals resembles the neck of the 

 whale, which not admitting of lateral motion, carry 

 the head forward with the same stiffness as if the 

 neck were one solid bone, and yet without the dan- 

 ger of fracture that might result from a structure of 

 that description. The transverse processes of the 

 vertebrae of the neck are very long, and assist in sup- 

 porting that portion of the buckler by which the neck 

 is covered, so that the spinal structure of the neck 

 and its exernal covering both conduce to the same 

 end, that of giving stiffness ; and there is no doubt 

 that the buckler diminishes or destroys any strain 

 upon the cervical spine which might tend to injure 

 the spinal cord. 



The dorsal vertebra?, which are represented as 

 being twelve in number, are not anchylosed, but 

 they admit of very little motion ; and their spinous 

 processes, which are much produced, are directed 

 backwards, and bear against the buckler like 

 props or stays. The hinder dorsal vertebrae and 

 the lumbar ones, which are three in number, have 

 the processes still more produced, and directed 

 outwards and forwards, so as more completely to 

 support and bear up the heavy armed covering of the 

 animal at that part of the body where there are no 

 ribs. After the spine (which generally consists of 

 eight sacral vertebrae posterior to the lumbar ones) 

 is past, the bones of the pelvis are so formed as to 

 give support to the plate on the crupper. At the 

 anterior edge of the pelvis, the ilia rise into two short 

 but thick props ; and at the posterior, the tubero- 

 sities of the ischia rise in the same manner, and by 

 these four bony prominences the plate is completely 

 supported. 



In considering this structure, we find two results : 

 in the first place, any pressure which is communi- 

 cated to the anterior extremity of the spine, or, which 

 is the same in effect, any resistance to the motion of 

 the spine forwards, is so transferred to the plates of 

 the armour, that these divide the strain, and in 

 great part take it off that organ ; secondly, from the 

 support given by the extended processes of the pos- 

 terior vertebrae, and the projecting processes of the 

 bones of the pelvis, the posterior part of the armour 

 is kept wide at the sides, so as not to interfere with 

 the contents or functions of the abdomen or pelvis, 

 the latter of which is large and wide in proportion to 

 the size of the animals. Such is the covering of the 

 upper part of those curious animals, and the means 

 (at least one of the means) by which that covering 

 is turned to account. We shall now briefly notice 

 the appearance and covering of the under side. 



The head, except the parts that have been men- 

 tioned as covered by the helmet or the hard tubercles 

 under the eyes, is covered with skin, and so is the 

 whole body below the armour, and the legs, with 

 less or more of hair upon it, according to the species. 

 There are also in some species numerous long hairs 

 in the interstices of the plates. The skin en the 

 under part of the body is beset with tubercles, and 

 they get hard and indurated on the legs and feet. 

 There are, however, none upon the soles on which 

 the animals walk, and these are also without hair. 

 The legs are short, and from the portion of them 

 that is covered by the armour, they look much shorter 

 than they really are. They are, however, very thick 

 and strong. The feet are large and flat, and have 

 the toes united by a membrane as far as the last pha- 

 lanx. **There arei in some, five on all the feet, and 



