336 FOSSILS FROM THE 



existence in some degree of the universally diffused sense of 

 feeling we neither need special evidence, nor can we receive 

 any. Even of the existence of one of the cerebral senses, — 

 that of taste, — we need expect no satisfactory proof : it is, of 

 all the senses, that which lishes are held to possess in the lowest 

 degree, and regarding which the comparative anatomist who 

 pursues his researches among even the recent fishes succeeds 

 in satisfying himself least. "Fishes," says Cuvier, in his 

 "Animal Kingdom," " can have little sense of taste. " " Natu- 

 ralists are generally disposed to conclude," says Dr Fleming, 

 in his " Philosophy of Zoology," " that the sense of taste can 

 scarcely be said to belong to this class of beings." " It does 

 not appear," the Doctor adds, "that it is ever used in the 

 discrimination of food, and does not furnish any character for 

 classification to the ichthyologist." And, of course, what it 

 does not furnish to the ichthyologist, who expatiates among 

 the living forms, it cannot be expected to present to the stu- 

 dent of fossil ichthyology. Even had it left its sign im- 

 pressed in the rocks, he could at best only doubtfully recog- 

 nise it as indicated by perhaps one or two uncertain foramina. 

 Respecting the sense of hearing in the first ganoids, our evi- 

 dence is better ; and we find it, on evidence, charged with a 

 curious and suggestive fact. The organs of hearing in the 

 placoids, — sharks and rays, — differ considerably from those 

 in the osseous fishes. The auricular passage opens externally, 

 as in the reptiles ; and the internal ear consists of a chamber 

 of considerable size, walled off from that of the brain by a car- 

 tilaginous partition. The brain-pan exists as a central cham- 

 ber, and the internal ears as two large closets placed beside 

 and behind it, and each furnished with its separate passage 

 that opens towards the nape. In the osseous fishes, on the 

 other hand, the organs of hearing have no communication 

 with the external surface, and they lodge in the same great 

 chamber which accommodates the brain : they are at least 



