Why does the fish require a large mouth?
How are the eyes protected? Compare the shape of the eye with the shape of the eye of a land animal.
Why are there no openings from the surface directly into the ears? Show the suitability of the fins as organs of locomotion in water.
REFERENCES
Silcox and Stevenson: Modern Nature Study
Nash: Fishes of Ontario (from Department of Education, free)
Kellogg: Elementary Zoology