REVIEWS

Book reviewed in this article: A Course in Biology . By J. J. B aker and G. E. A llen . Papers on Plant Systematics . By R. O rnduff . Die Entstehung der Arten und hoheren Kategorien . By H. L amprecht . Flora of Iraq , Vol. 9. Gramineae . By N. L. B or . (Ed. by C. C. T ownsend and E van G uest , with the collaboration of A li A l ‐R awi ). Wild Elowers of North Carolina . By W illiam S. J ustice and C. R itchie B ell . The Lichen Genera Cetrelia and Platismatia ( Parmeliaceae ). By W. L. C ulberson and C. F. C ulberson . Essays on Form in Plants . By C. W. W ardlaw . Crop Responses to Water at Different Stages of Growth . By P. J. S alter and J. E. G oode . Protons, Electrons, Phosphorylation and Active Transport . By R. N. R obertson . Encyclopedia of Plant Physiology, XVIII, Sexuality: Reproduction; Alternation of Generations . General editor, W. R uhland ; sub‐editor for this volume, H. F. L inskens . Annual Review of Plant Physiology , Vol. 19. 1968. By L. M achlis (Ed.). Biophysical Technique as Applied to Cell Biology . By J. C hayen and E. E. D enby . The Measurement of Environmental Factors in Terrestrial Ecology . British Ecological Society Symposium No. 8. Ed. by R. M. W adsworth et al . Guide to the Check Sheet for IBP Areas . IBP Handbook No. 4. By G. E. P eterken .