This journal provides immediate access to some articles. Volume 33(6); June 1947 Biochemistry Kynurenine as an Intermediate in the Formation of Nicotinic Acid from Tryptophane by Neurospora PMCID: PMC1079015 Botany On the Evolution of the Genus Nicotiana PMCID: PMC1079016 Antibiotic Substances from Basidiomycetes: I. Pleurotus griseus PMCID: PMC1079017 Antibiotics from Basidiomycetes: II. Polyporus biformis PMCID: PMC1079018 Embryology The Pole Cells of Diptera, Their Fate and Significance PMCID: PMC1079019 Mathematics A General Class of Problems in Conformal Mapping PMCID: PMC1079020 Physics Continuous Particles PMCID: PMC1079021 Radio-Wave Propagation and Electromagnetic Surface Waves PMCID: PMC1079022 Journal Matter Original table of contents page Administrative content — journal masthead, notices, indexes, etc. | ||