Contents

23 February 1973
Vol 179, Issue 4075

About The Cover

Polychromatism occurs (although infrequently) in many widely unrelated fishes, especially gold morphs. The condition is relatively common, however, in both sexes of the Midas cichild in and around lakes Nicaragua and Managua in Nicaragua. The female of the illustrated pair is gold. Their fry have been swimming for 1 day. See page 806. [George W. Barlow, University of California, Berkely]