REVIEWS

Books reviewed in this article: Speciation in Tropical Environments . Ed. by R. H. L owe ‐M c C onnell . Determination of Angiosperm Families by means of a Punched‐Card System . By B. H ansen and K. R ahn.Numerical Taxonomy . Ed. by A. J. C ole.Flowers of Europe—a Field Guide . By O. P olunin.Spring Flora of Minnesota, including Common Cultivated Plants . By T homas M orley.The Early Development of Irish Society: the Evidence of Aerial Photography . By E. R. N orman and J. K. S. S t J oseph.Plant Pathology . By G. N. A grios.Mycological Studies honoring John N. Couch . Ed. by W. J. K ock.Common Edible Mushrooms . By C lyde M. C hristensen . Fungal Parasitism . By B rian J. D everall.The Algae—A Review . By G. W. P rescott . An Introduction to the Principles of Plant Physiology , By W. S tiles and E. C. C ocking . Perspectives in Phytochemistry . Ed. by J. B. H arborne and T. S wain . Introduction to Plant Physiology . By J acob L evitt . Root Growth . Ed. by W. J. W hittington . Statistics and Experimental Design . By G eoffrey M. C larke . Ecological Aspects of the Mineral Nutrition of Plants . Ed. by I. H. R orison et al. Evolution and Phylogeny of Flowering Plants . By J. H utchinson .