This journal provides immediate access to some articles. Volume 26(2); February 15, 1940 Astronomy Galactic and Extragalactic Studies: V. The Period Frequency of Classical Cepheids in the Magellanic Clouds PMCID: PMC1078014 Remarks on Zwicky's Paper “On the Formation of Clusters of Nebulae and the Cosmological Time Scale” PMCID: PMC1078015 The Opacity of Extended Stellar Atmospheres PMCID: PMC1078016 Genetics A New Inherited Character in Man PMCID: PMC1078012 Influence of Female Stock on the Functioning of Small Pollen Male Gametes PMCID: PMC1078013 Mathematics Normal Algebraic Number Fields PMCID: PMC1078017 On an Ergodic Analysis of the Remainder Term of Mean Motions PMCID: PMC1078018 Groups Which Contain Less Than Fourteen Proper Subgroups PMCID: PMC1078019 On the Decomposition of Transitive Permutation Groups Generated by the Symmetric Group PMCID: PMC1078020 General Expansion Theorems PMCID: PMC1078021 Some Combinatorial Properties of Complexes PMCID: PMC1078022 On the Theory of Sphere-Bundles PMCID: PMC1078023 Zoölogy and Anatomy On the Synthesis of Cleavage Chromosomes PMCID: PMC1078011 | ||