778 ALLIS. 
EXPLANATION OF PLATE XXIII. 
Fic. 19. Top view of head of adult Amia. On the left side the dermal bones 
have been entirely removed ; on the right side they have been left in place, but 
scraped so as to expose the lateral canals and the ends of the nerves that innervate 
the canal organs. On the left side the anterior extension of the trunk muscles 
that fills the temporal groove has been removed. X 1%. 
Fic. 20. The same, a deeper dissection. The eyeball has been removed on 
the left side, the surrounding tissue being left in place and represented as trans- 
parent in its ventral portion so that the nerves below it can be seen. X I. 
