This one really had me intrigued so I decided to share it and see if you enjoy it as much as I did. I certainly thought it extremely clever. Have typed the verse below in case you have trouble reading the original.
Some are unable as you know
To tell the Crocus from the Crow;
The reason why is just because
They are not versed in Nature's laws;
The noisy, cawing Crows all come.
Obedient to the Cro-custom,
A large Crow Caw-cus to convoke.
You never hear the Crocus croak!