26 PISCES. 



6. Crescentic nerve, expanded on the sac containing the stone ; it originates from 



a branch of the auditory nerve and a filament from one of the bundles about 

 to form the trunk of the par vagum. 



7. A branch from the par vagum to the first partition of the gills ; it may be 



compared with the glosso-pharyngeal in the skate. 



8. Trunk of the par vagum, arising from the restiform body ; this is the last of 



the cerebral nerves. 



9. First spinal nerve. 



FIG. III. 



PART of the optic lobe has been removed for exposing the ventricle, which is con- 

 tinued from near the anterior lobes ; it passes under a commissure between the optic 

 lobes, and is continued under the cerebellum to the calamus scriptorius ; the longitu- 

 dinal bands or columns on its floor are not so distinct as in the skate. The anterior 

 point of the cerebellum, which was previously concealed, enters into the ventricle of the 

 optic lobes. There is not so distinct a cavity in the cerebellum as in that of the skate. 



FIG. IV. 



THE greatest part of the cerebellum has been removed from the preparation from 

 which the preceding figure was taken, for showing the continuation of the ventricle to 

 the calamus scriptorius. 



