360 SEEING AND HEARING. 



the expiration is made beneath the waves, or the creature 

 itself is either in a sportive mood or under the influence 

 of rage and terror." 



With respect to the senses of the whale, it may be said 

 that that of smell seems to be enjoyed by most of the 

 species, though not by the herbivorous cetaceans. 



Their eyes, not larger than those of an ox, are very 

 small when compared with the animal's bulk of body ; 

 but being placed far back in the head, and obliquely 

 above and behind the angle of the mouth, they command 

 an extensive range of view. The visual axis is directed 

 obliquely downwards, so as to assist the animal in dis- 

 covering the food floating beneath him ; and the power of 

 sight must be acute, inasmuch as he recognizes his con- 

 geners, when under the surface and in clear water, at a 

 very great distance. 



The whale's organ of hearing is marked by some pecu- 

 liarities. There is no external ear; but on the skin 

 being removed, a diminutive opening into the skull is 

 perceptible. The internal ear is hollowed out of a parti- 

 cular bone which forms no part of the ordinary cranial 

 bones, but is attached to it by cartilaginous ligaments. 

 It is situated just behind the eye, and about two feet 

 deep, and is not large enough to admit of the introduc- 

 tion of a man's little finger. What is known as the 

 " Eustachian tube" opens high up into those air-ducts 

 which, as we have explained, answer to the nose. 

 Through this channel it is that the animal must have the 

 sounds transmitted on the waves of air, and with this 

 channel must be connected the cavities in which, accord- 

 ing to some authorities, the olfactory nerves are situated. 



