Bass & Perch
Freshwater Basses
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Note how the mouth of the Largemouth extends under the eye, while that of the Smallmouth stops short of it. A lot of fishermen seem to think everything they catch is a Largemouth.
-- Wikipedia
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Bass are not suitable for the aquarium except in solitary confinement. They are extremely aggressive, and will kill any tank-mates.
-- Wikipedia
Yellow Perch
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-- Wikipedia