Ogden Nash, one of the great unappreciated American poets:

Cow
The cow is of the bovine ilk,
One end is moo, the other, milk.

Turtle
The turtle live 'twixt plated decks
Which practically conceal its sex;
I think it clever of the turtle
in such a fix, to be so fertile.

You wanna know what's really sad? I just typed those from memory.