Twentieth-century scholars of folklore such as Charles Oman noted that one element of the children's account, the entry into a different reality by way of a cave, seems to have been quite popular. Gerald of Wales, the medieval historian, tells a similar story of a boy who, after escaping his master, "encountered two pigmies who led him through an underground passage into a beautiful land with fields and rivers, but not lit by the full light of the sun". But the motif is poorly attested; E. W. Baughman lists it as the only example of his F103.1 category of English and North American folk tale motifs: "Inhabitants of lower world visit mortals, and continue to live with them". Martin Walsh considers the references to St Martin to be significant, and sees the story of the green children as evidence that the feast of Martinmas has its origins in an English aboriginal past, of which the children's story forms "the lowest stratum". A contributor to "Notes and Queries" in 1900 suggested a Celtic connection: " 'Green' spirits are 'sinless' in Celtic literature and tradition ... It may be more than a coincidence that the green girl marries a 'man of Lynn.' Here the original [Celtic word would be "lein", evil, "i.e." the pure fairy marries a sinful child of earth."