IXI'ELLIGENCE AND BRAIN PATTERN 



17 



fibres from certain peripheral sense organs kno^\•n as taste-buds 

 Avhioli are situated on the anterior part of the mouth, the lips, 

 and barbels (when present) and even the skin. Its function is 

 gustatory, i.e. the centre of taste perception, altliough the facial 

 nerve still sends a few motor fibres to certain neck muscles. 



This puzzles the human anatomist, who looks upon the facial 

 nerve as predominantly the motor nerve of the face muscles ; 



PLATE 1. 



OB 



PEB 



Cod. Catfish. Carp. 



P. — Pallium. PEB. — Primitive end-brain. OL. — Optic lobe. C. — Cerebellum. 

 AT. — Acoustic tubercle. S.S.L. — Somatic sensory. FL — Facial lobe. VL — 

 Vagal lobe. OB — Olfactory bulb. CLM — Cerebellum (removed in Fig. iii, 

 turned forwards in Fig. ii). 



however, even in man the facial nerve still receives gustatory im- 

 pulses from the anterior portion of the tongue by means of a recurrent 

 branch, known as the chorda tympani. 



It is quite obvious how this apparent contradiction in function 

 has arisen. In fish there are no facial muscles but an elaborate 

 gustatory system, on account of the nature of the medium in which 

 it lives ; whereas in man the facial, which by Sir Charles Bell 

 was called the respiratory nerve of the face, not only supplies 

 the styloid and hyoid muscles of the neck, but also has taken on the 

 supply of all the facial muscles as so fully described by Bell in his 

 " Anatomy of Expression." 



The course of the facial nerves within the brain of fish is so 

 characteristic that they are a useful guide to the recognition of the 

 facial lobe or lobes and their relation to other structures. In a 



