Bull. U. S. F. C. 1902. (To face page 48.) 
Plate 9. 
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2 . 
3 . 
4 . 
5 . 
Side view of aquarium, showing sounding apparatus at right-hand end and suspended glass cage in which the fish were confined. 
End view ol aquarium, showing sounding apparatus. 
Dorsal view of brain of Fundulus heteroclitus, dissected to show positions of the roots of the fifth and seventh nerves (V), the roots of 
the ninth and tenth nerves (X) , and the internal ear as indicated by its otolith. Enlarged about twice. 
Dorsal yew of head of J'lmdulus heteroclitus , to show the region where the following nerves were cut: The fifth and seventh (V), the 
_ eighth (VIII), and the lateral-line nerve (X). Enlarged about twice 
Side view of Fundulus heteroclitus , showing the region where the lateral-line nerve was cut (X). Slightly enlarged. 
