164 



MAMMALIA. 



relative size of whose nasal bone bears any pro- 

 portion to that of the hog, and though it is much 

 stronger in proportion, it is not so much produced 

 anteriorly. In fact, the enlargement of this bone in 

 the rhinoceros answers a very different purpose from 

 that which it answers in the hog. In the former it 

 seems intended chiefly to support the horn, as it is 

 called, or the two horns in the species which has that 

 number of those appendages. This horn, or these 

 horns, have no core of bone like the horns of oxen 

 and many other ruminating mammalia. They are 

 wholly a production of the skin, and each may be 

 regarded as a great tuft of bristles, somewhat resem- 

 bling baleen in their texture, but far more firmly sol- 

 dered together than the fibres of that substance. This 

 horn is a terrible weapon in the rhinoceros, and the 

 bone is made strong in proportion to the action of the 

 appendage. The nasal bone in the hog has no such 

 appendage to support, and therefore it is lengthened, 

 but inferior in breath and in thickness of substance. 

 Its office is to support the snout and its peculiar bone, 

 and this, though very efficient for the purpose to 

 to which the hog applies it, is so far from being fit 

 for a weapon of any kind, that a slight blow upon it 

 pains the animal more than a severe one upon any 

 other part of its body. The snout bone of the hog 

 rests at its under part upon the intermaxillary bones, 

 in front of the sockets which receive the incisive 

 teeth, and at the upper part it is united to the nasal 

 bone by cartilage. Its distal extremity supports the 

 peculiar organ which forms the snout properly so 

 called. This is composed internally of cartilaginous 

 fibres, and its termination, which is nearly circular, is 

 flat, but slopes inwards on the under side. It is 

 naked and full of follicles, which keep the surface 

 moist, and prevent its delicacy from being injured 

 by long exposure to humid earth. The extremity of 

 it forms a kind of elevated ring, and the tissue with 

 which it is enveloped is most abundantly sup- 

 plied with nerves and blood-vessels. This cu- 

 rious organ is put in motion by two large muscles 

 on each side, the upper one inserted in the boun- 

 dary of the cavity which receives the canine teeth, 

 and the under one in the lower part of that cavity. 

 These muscles, as well as the muscles which work 

 the jaws are much larger than they are in any animal 

 which has the nose merely as an organ of smell ; and 

 their tendons divide into a vast number of fibres, 

 which terminate in the tissue that forms the envelope 

 of the snout. Those fibres take a great many di- 

 rections, straight, oblique, and spiral, so that the 

 motions which they can communicate to the organ, 

 though limited in range, are very various in direction. 

 The great supply of nerves and blood-vessels point 

 out the sensibility of the organ ; for though, as we 

 have said, we are not warranted in concluding that 

 nerves alone, and without the other systems, are or 

 could be organs of sensation, yet it is certain that 

 where there are no nerves there is no direct sensa- 

 tion, and perhaps not much sensibility. The opening 

 of the nostrils terminate in the disc of the snout, and 

 its elongation beyond the nasal bone gives farther 

 scope for the development of the organs of smelling, 

 so that it is highly probable that this sense is most 

 acute in the hog. The sense of smelling is not, how- 

 ever, the proper sense which is allocated in the disc 

 and naked part of the snout ; for it is also a very 

 sensitive organ to what is called touch. The elevated 

 ring with which the upper part of the disc of the 

 snout is furnished, and which the animal can elevate 



and depress, and move in a great many ways, is the 

 instrument with which it "roots" or turns up the 

 soil. Its action is not unlike that of a plough with a 

 double mould board which turns the furrow both 

 ways, and the projecting ring performs an office 

 something similar to that of the cutting feather of the 

 sock, only it turns up the soil as well as cuts it, with- 

 out any necessary elevation of the head. It is in 

 quest of the succulent roots of plants that the hog 

 performs this operation, or in the wild state it is in 

 quest of acorns, beech mast, and other forest fruits, which 

 are covered up with fallen leaves, and the mud which 

 is collected or produced by these. When seeking 

 this description of food in places where it is naturally 

 to be found, the hog has comparatively light work ; 

 but in moist places where the roots of plants are large 

 and succulent, its labour is more severe. Even in 

 such places, however, it "nozzles" away with great 

 satisfaction, and utters a grunt of apparent delight 

 when it comes to a root more rich or racy than the 

 rest. As the animal is not very handsome in its 

 form, or particularly cleanly in its manners, it is no 

 great favourite with any body, except those who make 

 a profit of it ; but still it is an animal whose economy 

 is worth studying, and the structure and action of 

 whose ploughing apparatus are highly curious. It 

 does its work with such apparent ease, that we are 

 not aware of either the complication of structure, or 

 the strength of muscle which it requires, but they are 

 both very great. The following figure affords a 

 slight idea of the external form of this peculiar 

 organ ; but its action, and the internal organisation 

 which fit it for this action, are both studies of in- 

 tricacy as well as instruction to every one who 

 wishes to understand the mechanical action of animals. 



There is another short lesson which we may learn 

 from this instrument, and that is the limitation even 

 of the acutest senses of animals to the uses which 

 the animals have for them. There is little doubt that 

 the sense of smelling in the hog is far more acute 

 than the same sense in man ; and it is probable also 

 that no single portion of the surface of the human 

 body is so completely endowed with what is called 

 touch, as the naked extremity of this organ. But 

 notwithstanding this sensitiveness in both respects, it 

 does not extend beyond the discriminating and find- 

 ing of the animal's food, in either of them. The keen- 

 nosed hog is proverbially indifferent to the most 

 offensive odours ; and its highly sensitive snout can 

 poke about among substances which we would reckon 

 in the highest degree harsh and grating to the touch. 

 There is no feeling of pleasure or of pain resulting 

 from odour or from touch in the animal ; and if he 

 should find food in the one place, and not in the 

 other, " the reek o' the rotten fens" would be far more 



