Another version of the one quoted by Anne Cormack:

Icky Wicky was a worm,
But Icky Wicky couldn't squirm
Sat upon the railway line,
Didn't see the train in time
...ICKY WICKY!

Fuzzy Wuzzy was a bear
But Fuzzy Wuzzy had no hair.
So Fuzzy Wuzzy wasn't fuzzy,
Was he?

I wish I were a catterpiller
Life would be a farce
Sliding down the cabbage leaves
and landing on my...hands and knees

Nigel