A RECENT publication by R. E. Savage and R. S. Wimpenny (“Phytoplankton and the Herring”, Part 2 (1933 and 1934), Min. Agric. Fish., Fishery Invest., Ser. II, 15, No. 1 (1936), pp. 1-88. London: H.M. Stationery Office, 1936. 4s. 6d.) gives detailed information on the plankton conditions in the southern North Sea and their relations with the herring fishery in the years 1933 and 1934. This is a continuation of work already begun in 1921 and follows on a previous report for the years 1921-32. The year 1933 was remarkable for unusually dense patches of the diatoms Rhizosolenia styli/ormis and Biddulphia sinensis. The former is associated with the current system in the neighbourhood of the south-west Dogger Bank Swirl; and the unusual degree of production in 1933 appeared to owe its origin to a strong incursion of oceanic bottom water, from the north, rich in nutrient salts. The arrival of the East Anglian herring shoals was delayed by these diatom patches in October 1933. A remarkable condition is recorded in May 1933, when a large area was covered with masses of the diatom Coscinodiscus concinnus to a depth of four feet, in which several guillemots and puffins were found floating dead. This was apparently being eaten by fulmar petrels.