This journal provides immediate access to some articles. Volume 19(9); September 1933 Anthropology A Tree-Ring Chronology for the Rio Grande Drainage in Northern New Mexico PMCID: PMC1086188 Biochemistry Crystallization of a Compound of Hemoglobin and Carbon Dioxide PMCID: PMC1086194 Botany A Preliminary Survey of the Species of Zostera PMCID: PMC1086190 Chemistry Urease Activity as Influenced by Oxidation and Reduction PMCID: PMC1086201 The Electron-Diffraction Investigation of the Structure of Molecules of Methyl Azide and Carbon Suboxide PMCID: PMC1086202 The Electron-Diffraction Investigation of the Molecular Structure of Cyanogen and Diacetylene (with a Note on Chlorine Dioxide) PMCID: PMC1086203 Genetics Interchange between X- and Y-Chromosomes in Attached X Females of Drosophila Melanogaster PMCID: PMC1086195 Pollen Tube Establishment and the Deficiency of Waxy Seeds in Certain Maize Crosses PMCID: PMC1086196 The Effect of Homozygous Genes for Self-Sterility PMCID: PMC1086197 Geology Some Observations on the Archean Metamorphics of the Grand Canyon PMCID: PMC1086189 Mathematics On Criteria for Fourier Constants of L Integrable Functions PMCID: PMC1086198 Groups Whose Operators Have No More Than Three Distinct Squares PMCID: PMC1086199 Logarithmic Solutions of Bianchi's Equation PMCID: PMC1086200 Pathology Concentration and Purification of a Growth Inhibitor Extracted from Kidney: A Preliminary Report PMCID: PMC1086192 Physics Remarks on Superconductivity PMCID: PMC1086191 Physiology Oxidation-Reduction Potential of Ascorbic Acid (Vitamin C) PMCID: PMC1086204 Psychology The Abolishment of a Discrimination PMCID: PMC1086193 Journal Matter Original table of contents page Administrative content — journal masthead, notices, indexes, etc. | ||