Eleven stands of umbilicate lichens exhibiting a range of variabilities in enzyme banding patterns were compared on the basis of the ultraviolet (UV)absorbing properties of thallus extracts. Stands of Umbilicaria veilea, which were some of the most variable enzymatically, had the lowest UV absorbancy in extracts, and stands of Lasallia papulosa, which were among the least variable enzymatically, showed more UV absorbance than others. Umbilicaria deusta, U. muhlenbergii and U. mammulata had intermediate levels of absorbance. Negative correlations (P = 005–007) were found between enzyme polymorphism and UV absorbance in the ranges 215–220, 269–271 and 304–305 nm. There was also a significant negative correlation at P = 003 between enzyme variability and thallus dry weight extractable with either ethanol or acetone.