[en] The question of whether galaxies' masses M and luminosities L may be related by a power law M proportional L².⁵/sup B/ rather than a direct proportionality is raised in relation to two problems. First, the effect of Bnot-equal0.4 on the problem of galaxy-cluster masses is examined. Second, a preliminary investigation of binary elliptical galaxies suggests B=0.3plus-or-minus0.1 (s.e.). A value of B=0.3, with a mass-luminosity ratio of 260 for the brightest cluster member as suggested by Jenner's work, indicates a typical cluster mass-luminosity ratio of 580