In the 1940's and 1950's one of the most obvious candidates for fish sperm (and indeed egg) storage were the salmonids. There seemed to be an underlying problem in that sperm remains viable for a very short time once diluted with water.This is not so in the herring (admittedly a less obvious candidate for pisciculture) in which the sperm survives, and can fertilize eggs, after several hr in seawater. Yanagimachi (1953) stored herring gametes in Ringer's solution with resultant viability of 24 hr or more. Would egg yolk as an extender be superior to Ringer's solution? Blaxter (1953) found that egg yolk in borate or phosphate buffers as a diluent allowed fertilization rates in herring of 20% to 30% after 4 d. In fact, this apparent improvement in viability could be matched by storing the gonads dry at 4 oC; after 4 d 50% to 60% fertilization rates could be achieved.