New measurements are reported of the fluorescence polarization ratios for pure anthracene crystal. The values for different crystals lie in the range b/a= 4.5–6.5 : 1. The 0—0 band group is excluded, being affected by re-absorption. The 0—1, 0—2 and 0—3 bands have PR values nearly equal to one another in any one crystal, but differing from crystal to crystal according to method of preparation and other conditions. A theoretical interpretation is discussed.