310 



liim ami does not fail to distinguish his stick from a gun. The doj( looks into 

 your face, but you can not tell whether he is looking into your eyes or at your 

 mouth. He has an indefinite gaze, and, like most mammals, is not satisfied with 

 the sense of sight alone, but must confirm and improve with the sense of smell 

 and hearing. 



In conclusion, we may say, that though all animals may have the power of 

 accurate observation, yet the power to perceive the delicate lines and shades of 

 an object distinctly seems to reside only in tliose forms whose retinal development 

 has reached the highest stage, that is, a fovea centralis. 



