408 THE SENSORIAL FUNCTIONS. 



and which he was not long in discovering and 

 securing. 



Another experiment, the converse of the first, 

 was next tried. A large dead hog was concealed 

 in a narrow and winding ravine, about twenty 

 feet deeper than the surface of the earth around 

 it, and filled with briers and high cane. This 

 was done in the month of July in a tropical 

 climate, where putrefaction takes place with 

 great rapidity. Yet, although many vultures 

 were seen, from time to time, sailing in all di- 

 rections over the' spot where the putrid carcass 

 was lying, covered only with twigs of cane, none 

 ever discovered it; but in the mean while, 

 several dogs had found their way to it, and had 

 devoured large quantities of the flesh. In an- 

 other set of experiments it was found that young 

 vultures, enclosed in a cage, never exhibited any 

 tokens of their perceiving food, when it could 

 not be seen by them, however near to them it 

 was brought.* 



It has been doubted whether fishes, and other 

 aquatic animals, possess the sense of smell ; in 

 some of the Whale tribe, indeed, neither the or- 

 gan of smell nor the olfactory nerves are found-t 

 Some physiologists have gone the length of de- 



* Edinburgh New Journal of Science, ii. 172. The accuracy 

 of these results, which had been contested by Mr. Waterton, is 

 fully established by the recent observations and experiments of 

 Mr. Bach man, which are detailed in Loudon's Magazine of Na- 

 tural History, vii. 167. 



t Home; Lectures on Comparative Anatomy, i. 17. 



