Abstract: THE plaice (Pleuronectes platessa) in the open-air pond at the Port Erin Biological Station started spawning on March 3, and those at the Piel (Lancashire) Sea-Fish Hatchery (under cover) on March 1. This is about a week earlier than last year (March 9). It would be interesting to know how this record compares with that of fish in the sea. At the time of writing I have no returns that will give the information for the Irish Sea, though I hope to know later. Probably the officials of the International Investigation will be able to speak of the condition in the North Sea, and those of the Plymouth Biological Station in regard to the English Channel.