Just came accross this thread. I have come accross some alternative lyrics recorded on Songs of the Irish Travellers cd and sung by Michael McDonagh in 1972..

The Crabfish

Oh, there was a little man and he had a little horse
And his saddle and his bridle dicky-pole accross

Mr Deedle-um, Doodle-um,old Mr. deedle-umpa-die-do-day

For he rode and he rode till he came to the brook
And he see the little fisherman fishing with his hook

Mr Deedle-um, Doodle-um,old Mr. deedle-umpa-die-do-day

Saying, Oh Mr fisherman, oh fisherman if you catch a crafish
Give unto me and I'll bring it home

Mr Deedle-um, Doodle-um,old Mr. deedle-umpa-die-do-day

But the fisherman, the fisherman he cotch a crabfish
He gave it unto me and I brought it home

Mr Deedle-um, Doodle-um,old Mr. deedle-umpa-die-do-day

Oh, when I brought it home sure Id neither pot nor dish
And I put it in the chamber where me mother used to piss

Mr Deedle-um, Doodle-um,old Mr. deedle-umpa-die-do-day

The mother got up for to do alittle drop
And the little oul crabfish stuck to her spot

Mr Deedle-um, Doodle-um,old Mr. deedle-umpa-die-do-day

Oh husband, oh husband, as sure as you are born
The devils in the pisspot giving me the horn

Mr Deedle-um, Doodle-um,old Mr. deedle-umpa-die-do-day

Oh, the master got up and he run for the whip
And the more he beat the codfish the more he held his grip

Mr Deedle-um, Doodle-um,old Mr. deedle-umpa-die-do-day

He beat him in the head and he kicked him in the side
And then the little codfish, then he did die

Mr Deedle-um, Doodle-um,old Mr. deedle-umpa-die-do-day