This journal provides immediate access to some articles. Volume 7(8); August 1921 Chemistry An Apparatus for Determination of the Gases in Blood and Other Solutions PMCID: PMC1084857 Genetics Non-Disjunction and the Chromosome Relationships of Drosophila willistoni PMCID: PMC1084856 A Case of Rearrangement of Genes in Drosophila PMCID: PMC1084859 Mathematics Geometric Aspects of the Abelian Modular Functions of Genus Four (I) PMCID: PMC1084862 Mineralogy Melanovanadite, A New Mineral from Mina Ragra, Pasco, Peru PMCID: PMC1084863 Paleontology Adaptive Radiation and Classification of the Proboscidea PMCID: PMC1084858 Physics A Remeasurement of the Radiation Constant, h, by Means of X-Rays PMCID: PMC1084860 The U-Tube Absolute Electrometer PMCID: PMC1084861 Physiology Some Physical Characteristics of the Ear PMCID: PMC1084855 Journal Matter Original table of contents page Administrative content — journal masthead, notices, indexes, etc. | ||