ANIMAL PHYSIOLOGY. 



161 



AM.MAL PHYSIOLOGY. V. 



mi: i:.\i: 



THK external oar of brutes is ofton BO marked a feature in Hi-- 



.lii"<, it ii'Ms BO much grace and finish to the 



vomenta give such animation to the gestured, and it 



-o ornamental, that it is almost f 

 tin- reader that its form and folding* sir.' 



throughout tho class Mammalia. Every one who is alivo to 



of iiuiiiiatod nature and there are fow who arc 



dead to their attractions must have looked with di-li-ht on tho 



ear of : !, with its tassel of soft brown hair. That 



be, the rabbit, tho dainty littlo fcnnoo fox, 



T, despite tho excelling majesty of its 



horns, would all cut but sorry figures without tho external ear. 



strongest forms of cars, wo may mention that of 



which makes liim look like a warrior 



i double whii'ld. So flat and ample aro these ears 



that Sir Samuel Uaker cut a tolerably good mattress out of one 



of them. The membraneous and delicate ear of our larger 



It hon been remarked, that while the ear* of carnivorous 

 animal* are directed forwards, thoM of herbivorous animal* 

 nod backwards ; so that, in the pursuit of the latter 

 by tho former, the cars of both are so placed as to catch 

 the sound from the object whose movements it is of the highest 

 importance they should ,be acquainted with. Perhaps this idea 

 has been dwelt on too much, yet every one must have noticed 

 how the cat, the fox, and the ferret, carry their ears pricked 

 forward, while the ears of the deer and hare are, at least, a* 

 readily turned backward as forward. In the case of the ham, 

 however, tho shape and direction of the ear seems to be given 

 in relation to tho hubit it has of crouching in its form. While 

 in its form, tho long ears stretch along the flanks, with their 

 orifices turned outward, and must be very efficient in appre- 

 hending tho sounds which proceed from tho feet of man or dog 

 as they beat the stubble. 



Tho concha, or external ear, is very generally found through- 

 out the whole of tho class Mammalia, but in a few it is " con- 

 spicuous from its absence." Thus, two of our native in- 

 sectivorous mammals, tho mole and tho shrew, are without it 



THE AFRICAN ELEPHANT. 



English bat is proportionately as monstrous, but instead of 

 being flat, its foldings are so decided, that it looks like an ear 

 within an ear. The long trumpet-shaped ear of ruminants and 

 horses, capable of being turned in any direction, is admirably 

 suited by its shape, and by tho fringe of hair which encircles it, 

 and partially extends across its orifice, to accomplish the double 

 purpose of receiving aerial waves, and excluding any small par- 

 ticles of dust, rain, or hail, which would otherwise get down to tho 

 sensitive tympanum. This oifiae of protection is, indeed, by no 

 means unimportant, as any foreign body on the drum membrane 

 canses exquisite annoyance, and the steadiest horse will become 

 restive when thus troubled. In the setter and spaniel dogs, tho 

 function of protection seems paramount to that of collection of 

 sounds, so that tho thick matted ear hangs down, when at rest, 

 right over the orifice of the ear. In the above cases the ear is 

 not only an organ of definite utility, but of conspicuous beauty, 

 and, indeed, it is a fine exemplification of how use and beauty 

 go hand in hand throughout all God's works. Why stupidity 

 should, in popular estimation, be especially associated with the 

 ears of the ass, is even more inexplicable than why it should be 

 considered as the special attribute of that much-abused animal. 

 The fairy Titania, when "enamoured of an ass," showed a 

 discriminating appreciation of good points when she kissed tho 

 "fair larfc'o card" of her "gentle joy." 



VOL. L 



In tho whale and his tribe, it is not only absent, but the very 



foramen which leads to the internal ear in this enormous animal 



will scarcely admit a pin. Indeed, this entrance to the ear 



seems to be retained only to establish or strengthen the affinity 



between the whale and the land mammalia, for tho impressions 



of sound are probably conyeyed to tho internal ear through the 



substance of the animal's body, as in tho case of fish. The 



tympanic cavity, however, is kept supplied with air by an 



i eustachinn tube that communicates with the passage which 



runs to tho blow-hole near that orifice ; BO that when the monster 



discharges the air from tho reservoir of its lungs with so forcible 



{ a jet that it carries the sea- water before it like a fountain, the 



! air of the tympanic cavity is, at the same time, partially renewed ; 



I and when he plunges once more unseen into the depths, this 



| cavity is in communication with the air he carries with him. 



j This arrangement, whereby sound, which has been conveyed 



! from the exterior through the solid structures of the bo<~:; 



made afterwards to traverse, or to be regenerated in, an internal 



air cavity, is not uncommon among the denizens of the water, 



and sometimes it is effected by such singular contrivances, as we 



shall find when we describe the ear of some fish, that we are 



almost justified in supposing that there is some quality in tho 



vibrations of an elastic fluid, like the air, which makes it a 



better medium for transmitting sound to the nerve fitted to 



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