Composite of floating material: The singer goes to the garden to pick flowers. He wishes he were a fisher, to catch Molly, a salmon; he wishes he were a scholar. He would build Molly a castle. But he lost her by courting too slow
Another composite of floating verses; see the cross-references. Sam Henry's earlier text, "The Star of Benbradden," starts with an original verse, but the rest is the same as "If I Were a Fisher." Since they're both composites, I decided to lump them -- and use the "If I Were a Fisher" name as more memorable.
I tossed Betty Garland's "Lovely Nancy" here on the same principle; it's massively composite, in the "Pretty Saro/If I Were a Fisher" mold.
Creighton's single stanza is really just a floating verse, but it's a floating verse often found with this song; this is as good a home for it as any. - RBW