This journal provides immediate access to some articles. Volume 14(3); March 1928 Astronomy On the Motion of the Magellanic Clouds PMCID: PMC1085449 Biology Intra-Seasonal Cycles of Growth PMCID: PMC1085445 Studies on the Biochemical Differences between Sexes in Mucors: 4. Enzymes Which Act upon Carbohydrates and Their Derivatives PMCID: PMC1085446 Botany Induced Immunity in Plants PMCID: PMC1085447 Mathematics On the Separation of Points of a Continuous Curve by Arcs and Simple Closed Curves PMCID: PMC1085441 On Some Properties of One-Valued Transformations of Manifolds PMCID: PMC1085442 Harmony as a Principle of Mathematical Development PMCID: PMC1085443 Note on the Behavior of Certain Power Series on the Circle of Convergence with Application to a Problem of Carleman PMCID: PMC1085444 Physics Anode and Cathode Sparks Differentiated by the Mucronate Electrode PMCID: PMC1085451 A Spectroscopic Criterion for the Benzenoid Structure in Some Types of Triphenylmethane Derivatives PMCID: PMC1085452 The Dispersion by Hydrogen-Like Atoms in Undulatory Mechanics PMCID: PMC1085453 The Production of Active Nitrogen PMCID: PMC1085454 On the Quantum Theory of the Ramsauer Effect PMCID: PMC1085455 The Fifth Dimension in Relativistic Quantum Theory PMCID: PMC1085456 On the Extension of Thermodynamics to General Relativity PMCID: PMC1085457 On the Variation of the Electromotive Force in a Photoactive Cell, Containing a Fluorescent Electrolyte, with the Intensity of Illumination PMCID: PMC1085458 A Note on Corona at High Humidity PMCID: PMC1085459 The Spark Spectrum of Neon PMCID: PMC1085460 Physiology On the Binocular Fusion of Colors and Its Relation to Theories of Color Vision PMCID: PMC1085448 Statistics On Hierarchical Correlation Systems PMCID: PMC1085461 Zoölogy Artificial Production of Janus Embryos of Chaetopterus PMCID: PMC1085450 Correction On the Classical Dirichlet Problem for General Domains PMCID: PMC1085462 Corrects: On the Classical Dirichlet Problem for General Domains. Proc Natl Acad Sci U S A. 1926 June; 12(6): 397–406. Erratum Application of the Law of Similitude to Hydraulic Laboratory Research PMCID: PMC1085463 Corrects: Application of the Law of Similitude to Hydraulic Laboratory Research. Proc Natl Acad Sci U S A. 1927 September; 13(9): 684–688. Journal Matter Original table of contents page Administrative content — journal masthead, notices, indexes, etc. | ||