This journal provides immediate access to some articles. Volume 43(3); March 15, 1957 Genetics EFFECT OF RIBONUCLEASE ON CROSSING OVER IN Drosophila PMCID: PMC528427 THE NATURE OF THE CHANGES EFFECTED IN CHROMOSOMAL MATERIALS BY THE CHELATING AGENT EDTA PMCID: PMC528428 THE PROBLEM OF DOMINANT LETHALS IN Drosophila Melanogaster FEMALES PMCID: PMC528433 THREE DIPLOID CHROMOSOME NUMBERS OF MAN PMCID: PMC528434 Mathematics THE ASYMPTOTIC DISTRIBUTION OF EIGENFUNCTIONS AND EIGENVALUES FOR SEMI-ELLIPTIC DIFFERENTIAL OPERATIONS PMCID: PMC528429 IRREDUCIBLE OPERATOR ALGEBRAS PMCID: PMC528430 ZEROS OF NEIGHBORING HOLOMORPHIC FUNCTIONS PMCID: PMC528431 Zoölogy and Anatomy A PRELIMINARY NOTE ON EXCITATION-CONTRACTION COUPLING PMCID: PMC528432 ON THE RELATIVE ABUNDANCE OF BIRD SPECIES PMCID: PMC528435 Journal Matter Original table of contents page Administrative content — journal masthead, notices, indexes, etc. | ||