re: the Caribbean life of this song, I just wanted to bring attention to the Lomax-recorded song "Willie Boy" in Nevis/St. Kitts:

http://www.amazon.com/Willie-Boy/dp/B0010WFIJK

re: Dave's comment, "Stan should know." Or, I'd say, "Stan read it in a book somewhere." It's quite unclear (I think purposefully so) how this song may have fit into Hugill's direct experiences. I haven't seen it appear under the guise of a shanty until Terry's book (1921) -- that's the first version Hugill prints (though he makes a couple lyrical changes that are suspicious!). Though the song up to that point, as far as I am seeing, had not been documented elsewhere as a shanty, recording artists during the shanty "boom" in the 1920s did recorded it among classics like "Rio Grande." By the time Hugill would have gone to see, even shanty aficionados (home listeners) might have considered "Billy Boy" to be a classic shanty in its own right. However, I am skeptical whether it had ever been much of a chanty or else just another one of many "regular" songs that were haphazardly sung by localized crews in later days.

I don't know where Hugill's second version comes from. He doesn't say. Usually, if he learned it at sea, he says who he learned it from, so I'm leaving open the possibility that he sourced it elsewhere.