64 EVERS'S COMPARATIVE ANATOMY. 



rally supposed that birds of prey are gifted with an acute sense of 

 smell, but the experiments of Mr Audubon go to prove the reverse 

 opinion ; and according to the researches of Scarpa, the following is 

 the order in which it is enjoyed, beginning with those in which it 

 is most acute ; grallatores, natatores, raptor es, scansores, inses- 

 sores, rasores. 



The organs of smell in the mammalia are distinguished by the 

 more perfect formation of external nose, by the large size of the 

 nasal cavities, and by the latter receiving several new openings, 

 such as the frontal, nasal, ethmoidal, sphenoidal, and maxillary 

 sinuses. The external openings are valvular in the beavers, seals, 

 and camels, and variously modified in other animals, according to 

 their different habits, as in the hog, elephant, &c. The turbinated 

 bones are long and simple in the rodentia, ruminanlia, and pachy- 

 dermata, and they form a complicated series of labyrinths in the 

 carnivorous tribes, where an acute sense is so necessary to enable 

 them to pursue their prey through their dark retreats. The large 

 olfactory nerves pass through the numerous openings of the cribri- 

 form plate, except in the cetacea, to be distributed on the surface of the 

 turbinated bones. These nerves are large and hollow in the human 

 foetus, like the olfactory tubercles of quadrupeds, and it is interest- 

 ing to observe how the sense of smell preponderates over all others 

 in the new born child, this can be easily tested during the nuzzling 

 of the infant at the mother's breast, when the loudest sounds may 

 assail its ears without effect, and when its visual powers are limited 

 to the mere perception of intense light. 



Taste. — A considerable degree of obscurity prevails, respecting 

 the enjoyment of this sense in the different classes of animals, and 

 although we cannot display any organ especially appropriated to it 

 in the inferior tribes of animals, yet it is supposed that all enjoy it, 

 from the polygastric animalcules up to man. It is generally seated 

 in, but by no means confined to the tongue, this organ being absent 

 in some instances even in the human subject, where the existence 

 of the sense has been proved; and in other cases, where the tongue 

 does exist, its dense horny nature excludes it from such an enjoy- 

 ment. The form of the tongue differs considerably in different 

 animals; in none, not even in the simiae, is it exactly like that of 

 man. In the cephalopoda distinct gustatory villi cover its surface ; 

 in many fishes it has no papillae, and in others it is set with teeth ; 

 in the chameleon it is an organ of very peculiar mechanism, and 

 admits of being protruded for several inches in pursuit of prey, with 

 amazing celerity and precision. This power, for a long period a 

 paradox with naturalists was discovered by Dr. Houston to be of an 

 erectile nature. In birds it serves chiefly as an organ of prehension, 

 in a few only does it possess papillae, being generally sheathed in 

 front by horn. With few exceptions among the edentata, the 

 tongue in the mammalia serves as an organ of taste. In the bisulca 

 it is covered with a thick epithelium ; in the bat, the opossum, and 



