B. IV.l THE HISTOEY OF ANIMALS. 91 



the spinal cord, reaching from the socket of the eye, and 

 ending upon the upper sharp teeth. 



3. All other animals are endued with the perception of 

 colours, sounds, smells, and taste. All animals have the 

 fifth sense, which is called touch. In some animals the 

 organs of sense are very distinct, and especially the eyes, 

 for they have a definite place, and so has the hearing. For 

 some animals have ears, and others open perforations : so 

 also of the sense of smelling, some animals have nostrils, 

 others passages, as the whole class of birds. In the same 

 way the tongue is the organ of taste. 



4. In aquatic animals and those called fish, the tongue is 

 still the organ of taste, though it is indistinct, for it is 

 bony, and not capable of free motion. In some fish the 

 roof of the mouth is fleshy, as in some cyprini among river 

 fish, so that, without careful examination, it appears like a 

 tongue. That they have the sense of taste is quite clear, 

 for many of them delight in peculiar food, and they will 

 more readily seize upon a bait formed of the amia and other 

 fat fishes, as if they delighted in the taste and eating of 

 such baits. 



5. They have no evident organ of hearing and smelling, 

 for the passages which exist about the region of the nostrils 

 in some fish do not appear to pass to the brain, but some of 

 them are blind, and others lead to the gills ; it is evident, 

 however, that they both hear and smell, for they escape from 

 loud noises, such as the oars of the triremes, so as to be 

 easily captured in their hiding-places. 



6. For if the external noise is not loud, yet to all aquatic 

 animals that are capable of hearing, it appears harsh and very 

 loud ; and this takes place in hunting dolphins, for when they 

 have enclosed them with their canoes, they make a noise from 

 them in the sea, and the dolphins, crowded together, are 

 obliged to leap upon the land, and, being stunned with the 

 noise, are easily captured, although even dolphins have no 

 external organs of hearing. 



7. And again in fishing, the fishermen are careful to 

 avoid making a noise with their oars or net when they per- 

 ceive many fish collected in one place ; they make a signal, 

 and let down their nets in such a place that no sound of the 

 oar or the motion of the waters should reach the place 



