298t Retrospective Criticism* 



Farrar, and says that he found the external ear of the hedgehog " termin- 

 ating inferiorly in an open external auditory aperture." I believe that such is 

 never the case, but that, owing to a peculiarity in the relations of the tragus 

 and antitragus cartilages, and a singular structure of the helix, it is always 

 apparently closed, although it is not so in reality. On being accurately 

 examined, those cartilages will be found approaching very nearly to each 

 other, so that the interval between them is but a small cleft scarcely ob- 

 servable; and they are surmounted by a kind of valve, which is a very 

 extraordinary developement of the internal point of the helix, and which 

 closes that cleft completely, causing the ear to appear as if it really had no 

 opening leading to the membrane of the tympanum. How C. S. E. could 

 overlook this circumstance I cannot conceive. It is very probable that 

 the animal can voluntarily raise or depress its valvular-like helix, so there 

 is no doubt but that it possesses the sense of hearing ; for, with the excep- 

 tion of the above peculiarity, its auditory structure, internal and external, 

 resembles that of mammiferous animals generally : it contains every organ 

 essential to the perfection of that faculty. If, as Dr. Farrar supposed, 

 it had no external auditory passage, that would not, as he concluded, war- 

 rant us in supposing that its ear was of no use to it ; for there is 



The Common Mole (Tklpa europae^a), and others might be mentioned, 

 whose external ear is wanting, yet its internal ear is remarkably deve- 

 loped, and it is certain that its hearing is very acute. This is a beautiful 

 provision of nature, which I cannot avoid noticing. The mole always 

 leading a subterraneous life; if it had external ears, they would be a con- 

 tinual source of annoyance to it, by their becoming filled with dirt, stones, 

 &c. How sounds are conveyed to this animal's tympanum, is a query not 

 at all satisfactorily explained. But in applying the principle of the adapt- 

 ation of means to ends, so admirably exemplified throughout all nature, 

 particularly in the organisation of animals, we come to an enigma which we 

 cannot solve, when we enquire for what purpose the forementioned singu- 

 lar provision should be conferred upon our common hedeghog. It must, 

 however, probably effect some important design hitherto undiscovered. 

 No other species of hedgehog has any provision of the kind, although one, 

 the jB^rinaceus auritus, which inhabits the eastern regions of Asiatic Rus- 

 sia, very closely resembles its European congener in all other respects, in 

 manners, habits, and general conformation, excepting the great length of its 

 external ears ; whence is derived the specific appellation auritus. Nor am 

 I aware of but one other animal, in the whole of the extensive order Car- 

 nassiers [carnivorous animals] of Cuvier, having its ear closed in a similar 

 manner, and that is 



The Water Shrew {Sorex fodiens of Linncsus). When this animal plunges 

 into the water, where it is said to spend a great part of its time, its ear 

 is almost hermetically sealed ; not however quite in the same way as the 

 hedgehog's ear is closed, but by means of three small valves, corresponding 

 with the helix, the tragus, and antitragus. The design in this instance 

 is obvious, to prevent the water from permeating into the external auditory 

 tube; by which it would not only be very painful to the animal's feelings, 

 but must eventually destroy its power of hearing. The similar provision 

 with which the hedgehog is endowed fulfils probably some equally import- 

 ant end, if it be true, as I firmly believe it is, that " the parts of animals 

 have all of them a real, and, with very few exceptions, all of them a known 

 and intelligible subserviency to the use of the animal." The hedgehog, 

 however, presents us with one of those " exceptions." I am, Sir, yours, 

 &c. — .7. J. Gelly, Montgomeryshire^ August ^ 1831. 



Those desirous of tracing the history of the water shrew farther are 

 referred to p. 79., and to the preceding notices there indicated. — J. i>. 



The Rallus Crex, or Corna-ake. — This bird has a strong muscular giz- 

 zard, notwithstanding the doubt expressed by A. K. Y. (p. 68.) in his 



