Many thanks to Malcolm Douglas for posting the tune for Flanders' version of "Gypsy Davy" (collected from Mrs. Woodbury). I've done some further looking and I discovered that John Harrington Cox, in 1939, published the same version of "Gypsy Davy" that Dorothy Scarborough has published in 1937. In fact, he got it from the same source, Mrs. Margaret Widdemer Schauffler of New York City. The head note reads:
"Contributed by Mrs. Margaret Widdemer Schauffler, New York City, Novermber 10, 1925. Obtained from Miss Lucis Sanderson, Cleveland, Ohio, who had it from an Englishwoman. Music noted by Miss Frances Sanders, Morgantown, Monongalia County (WVa)" [From FOLKSONGS MAINLY FROM WEST VIRGINIA by John Harrington Cox, published by the Works Progress Administration in June of 1939. This was subsequently published as TRADITIONAL BALLADS MAINLY FROM WEST VIRGINIA in 1939 and again in 1964(ed. George Boswell). Cox's version has been reprinted in Bronson's THE TRADITIONAL TUNES OF THE CHILD BALLADS, vol. 3(?),p. 205.]
Cox's and Scarborough's texts are almost identical, so I won't reprint Cox's version. Scarborough has "Gypsy Davy came over the hills,down thro the valleys shady," and Cox has "Gypsy Davy came over the hill, down through the valley shady." There is a difference in the chorus. Cox has:
>Ah dee doo, ah dee doo, doo day, >Ah dee doo, doo doo, day dee. >He whistled and sang ...
Cox does print a tune, which I have sent to Malcom Douglas to see what he can do with it. From what I can tell, it is quite close to the tune from Maine collected by Flanders. At least they are in the same family, and I would suggest related to Maguire's tune.
Unfortunately, Mrs. Widdermer/Schauffler gives two conflicting sources. She tells Scarborough that the song was "given to me orally by Mrs. Margaret Leamy, who learned it as a child in Ireland." She tells Cox that she got it from Miss Lucia Sanderson of Cleveland, who got it from an "Englishwoman". I don't know what to make of this.