With no immediate source of Chaucer's Prioress' Tale yet brought to light, postulations about the nature of this source, such as may be tentatively formulated from a study of the thirty-two available analogues of the miracle, have been made in order to estimate the extent and artistry of Chaucer's contribution to this tale of the little clergeon. Carleton Brown in his admirable studies published in 1910 and 1941 traced the development of the legend from what he considered the most primitive stage through Chaucer's story and the analogues which resemble it most closely. For this purpose Brown divided the thirty-three versions into three groups, A, B, and C, each of which represents a distinct form of the miracle and a distinct pattern of events.