I've previously encountered statements that "the" Burnside family (or rather, "a" Burnside family) had originally been Wallaces. R. J. Horace has already shown you the O'Hart pedigree. In my own records, I see that my late grandmother has photocopies of some pages from Walter Clark Armstrong's "Burnside-Underwood Genealogy" (1971). On page 9, Armstrong writes, "Records indicate that the Burnsides were originally Wallaces of the Wallace Clan of Scotland." But Armstrong doesn't bother to say what records he means.