THE staff of the Botanical Research Department of the Carnegie Institution of Washington has made many. valuable contributions to natural science, particularly in the study of desert vegetation, at the Desert Laboratory, Tucson, Arizona. The recently issued monograph on the Salton Sea is in many respects unique, for it deals with a remarkable series of phenomena, opportunities for the study of which are but rarely presented. That the Desert Laboratory workers have taken full advantage of this opportunity is evident from the perusal of this volume, interesting to the geologist, the geographer, and, above all, to students of plant ecology. The chief interest of this fine piece of co-operative research centres, as the editor and chief contributor point out, around the fate of organisms overwhelmed by floods, in the physical changes which follow emersion, and in the biological mechanism of reoccupation of sterilised areas as they emerge from the water—episodes which must have been repeated many times in the history of the earth's surface. The report gives the results obtained by the investigation from various points of view of the phenomena presented by a desert basin which has been the scene of alternate submergeuce and desiccation.