This sounds a bit like one i know a bit of from school-

big old bulldog
sittimg on the grass,
long came a bumble bee
stung him up the...
ASSk no questions,
tell no lies,
ever seen a copper
doing up his...
Flies are a nuisance
bees are a curse...

There was also a verse about Shakespere being a man of wit, which had to rhyme with shit of course.

Any one else able to add anything?