I found myself rummaging though an old anthology of Ogden Nash's comic verse, and found this delightful poem. If only Nash were an authority for why regulation of the Delta smelt is beyond Congress' power over interstate commerce!
Oh, why does man pursue the smelt?
It has no valuable pelt,
It boasts no escutcheon royal,
It yields no ivory or oil,
Its life is dull, its death is tame,
A fish as humble as its name.
Yet—take this salmon somewhere else.
And bring me half a dozen smelts.
(Ogden Nash, Good Intentions 38 (1942))