PISCES. 

 Fig. 530. 



997 



Diagram of the encephalon of the Perch, showing the general distribution of the cerebral nerves, 

 s, s, vestibule of the ear , other letters as in Jigs. 526, 527, and 528. (After Cuvier.) 



beneath the throat in front of the pectorals, they 

 are supplied from the same pairs of nerves ; 

 but in the abdominal division, where the 

 ventrals are situated towards the hinder part of 

 the body, they receive their supply from spinal 

 nerves placed proportionally further back. 



Sympathetic system. The sympathetic sys- 

 tem of nerves is in Fishes extremely small, so 

 much so, indeed, that its existence has been 

 denied by some anatomists; it is, however, in- 

 variably present, although its filaments are of 

 great tenuity. It runs along the sides of the 



531. 



Lateral and spinal nerves of the Cod ( Gadus morrhua). (After Swan.) 



1, 1, 1, dorsal communicating branch, derived from the fifth pair and nervus vagus, which joins all the 

 nerves of the dorsal fins 10; 2 and 3, two branches from the trunk of the par vagum passing down along 

 the side underneath the skin ; 4, branch running beneath the skin, which communicates with the inferior 

 branches of the spinal nerves , 8, 9, exit of the nerves from the spinal canal. 



spine, as in the higher Vertebrata, receiving 

 branches from each of the spinal nerves, and 

 anteriorly it communicates with a branch of the 

 fifth, and also with the nervus vagus. On the 



left side, after having sent a filament to join the 

 trunk of the par vagum on the stomach,* it 



* Swan, Comp. Anat. of Nerv. Syst. p. 24. 



