'The Hippopotamus'

"Oh, say, what is this fearful, wild,
Incorrigible cuss?"
"This *creature* (don't say 'cuss,' my child;
'Tis slang)--this creature fierce is styled
The Hippopotamus.
His curious name derives its source
From two Greek words: hippos--a horse,
Potamos--river. See?
The river's plain enough, of course;
But why they called *that* thing a *horse*,
That's what is Greek to me."

      -- Oliver Herford