Isopleth maps of M31 from an APM scan of a 75 minute exposure Palomar Schmidt IIIaJ plate taken by Sydney van den Bergh in 1970. The lowest isophote contoured is at a level equivalent to B = 27 mag arcsec⁻¹. Right: Distorted outer isophotes of M32 and NGC 205 after subtracting an elliptically averaged M31 profile. Cepa & Beckman (1988) quote tidal radii for M32 and NGC 205 of 0.84 kpc (0﹩\fdg﹩06) and 1.93 kpc (0﹩\fdg﹩14), respectively, which correspond to the relatively unperturbed inner parts of the profiles. Left: Location of the Davies (1975) H I cloud. In the southern half of the galaxy, the M31 outer isophotes are distorted in the direction of the stream. Although the lowest contour level is at the limit of reliability of the photographic data, this particular feature is present in other digitized wide‐area photographic data (e.g., WK88).