>The Plaice in Danish Waters.—The Fourth Report of the Danish Biological Station consists of a lengthy paper by Dr. C. G. J. Petersen “on the Biology of our Flat-fishes and on the Decrease of our Flat-fish Fisheries,” which was awarded a prize by Det Kongelige danske Videnskabernes Selskab, and which certainly deserves the careful attention of all who are interested in fishery questions. The first chapter gives a fairly complete account of some of the main features in the life history of the plaice in the Danish seas, together with shorter notes on other flat-fishes; the second and third are occupied by a discussion of the reasons for the deterioration of the fisheries, and of the remedial measures by which this evil may in the future be prevented. The paper is supplemented by five appendices, one of which, on the post-larval stages of flat-fishes, is of particular interest. For the full English translation with which we are provided English naturalists can but express their gratitude to the author.