32 ANATOMICAL CONSIDEEATIONS. 



sight; at all events, the author thinks he may conclude the far-famed 

 eye of the cat to be inferior to that of a horse. The domestic mouser is 

 -popularly said to see in the dark; the steed has been long known to 

 penetrate the gloom which sets the strained vision of its master at de- 

 fiance; but it remains to be granted that both horse and cat are equally 

 fitted to roam by night. The habits of the herbivorous creature would, 

 however, assert it to be possessed of such a faculty ; and the anatomist 

 discovers in the visual organ of the animal a provision specially adapting 

 it for these peregrinations. 



Upon the upper and forward surface of the inner, dark chamber, and 

 so placed as to catch, to concentrate, and to reflect every stray ray of 

 light upon the optic nerve, the tapidum lucidum is discovered within the 

 globe of the horse's eye. This structure is, after death, very bright or of 

 metallic luster, and, because of its concave form, is admirably adapted to 

 its particular function. That no doubt may remain as to the design of 

 such a provision, the tapidum lucidum is found only within the eyes 

 of those quadrupeds created to roam by night. It is altogether absent 

 in such animals as were destined to move about during daylight. 



DIAGRAM, EXPOSINQ THE INTERIOR OP THE HORSE'S EYE, AND DISPLAYING THE SITUATION OP THE TAPIDUM 

 LUCIDUM, OR GLOSSY SURFACE DEVELOPED WITHIN THE ORGAN. 



Tne tapidum lucidum, therefore, viewed in conjunction with the cor- 

 pora nigra, becomes an inferential proof that the horse originally inhab- 

 ited some land in which the, coolness of the night offered the greatest 

 temptation for pleasant pasturage. The Mighty Benefactor, conse- 

 quently, formed His creature to enjoy the bounties among which it was 

 permitted to roam. We know the cat was imported from the tropics ; 

 and, seeing that the eyes of both animals, in one marked particular, 

 resemble each other, we may conjecture the horse originally inhabited a 



