VEGETABLE LAMB MYTH. The barometz, or Vegetable Lamb of Tartary, a plant which, according to legend, grew sheep as its fruit and so was considered to be a possible source of cotton. The myth is similar to that whereby the gooseneck barnacle would turn into a barnacle goose. Woodcut from a 1725 English edition of Sir John Mandeville's 'Voiage and Travaile.