VISION. 355. 



This is probably a circumstance of considerable importance 

 with regard to our acquisition of correct perceptions by this 

 sense. 



In the magnitude of the organ compared with that of the 

 body, we may occasionally observe some relation to the cha- 

 racter of the animal and the nature of its pursuits. Herbi- 

 vorous animals, and especially those whose bulk is great, as 

 the Elephant^ the Rhinoceros ^\^i\ tlie Hippopotamus^ have 

 comparatively small eyes; for that of the elephant docs not 

 exceed two inches in diameter. The eye of the Whale is 

 not much more than the 200th part of the length of tlic body. 

 When the natural food of an animal is stationary and re- 

 quires no effort of pursuit, the eye is generally small, and 

 the sight less keen; while in the purely carnivorous tribes, 

 which are actively engaged in the chase of living prey, the 

 organ of vision is large and occupies a considerable portion 

 of the head; the orbit is much developed, and encroaches on 

 the bones of the face; while, at the same time, the bony par- 

 tition separating at the globe of the eye from the temporal 

 muscle is supplied by ligament alone: so that when that 

 muscle is in strong action, the eye is pressed outwards, 

 giving to the expression of the countenance a peculiar fe- 

 rocity. 



While nature has thus bestowed great acuteness of sight 

 on pursuing animals, she has, on the other hand, been no less 

 careful to arm those which are the objects of pursuit, with 

 powers of vision, enabling them to perceive their enemies 

 from afar, and avoid the impending danger. Thus, large 

 eyes are bestowed on the Rodentia and the Ruminantia. 

 Those tribes which pursue their prey by night, or in the 

 dusk of the evening, as for example the Lemur and the Cat, 

 are furnished with large eyes. Bats, however, form an ex- 

 ception to this rule, their eyes being comparatively small; 

 but a compensation has been afforded them in the superior 

 acuteness of their other senses. In many quadrupeds a por- 

 tion of the choroid coat is highly glistening, and reflects a 



