Analysis of Factors Determining Yield in Crop Plants. I. Varietal Differences in Yield of Grain and Straw of Wheat As Influenced by Photoperiodic Treatments.

Analysis of Factors Determining Yield in Crop Plants. II. The Influence of Photoperiodic Treatments on Characters Determining Yield in Wheat with Special Reference to the Temperature of the Ripening Period.

Mineral Nutrition of the Cotton Plant.

A Re-examination of the Supposed Effect of Riboflavin on Growth.

Participation of Cytochromes in the Respiration of the Aroid Spadix.

Growth Stimulation of Avena Coleoptiles.

The Dark Fixation of CO₂ by Succulent Leaves: Metabolic Changes Subsequent to Initial Fixation.

The Products of CO₂ Fixation in Leaves of Long- and Short-Day Treated Kalanchoë blossfeldiana.

Studies on the Organ of Production of the Natural Gibberellin Factor in Higher Plants.

Mechanical Properties of the Avena Coleoptile As Related to Auxin and to Ionic Interactions

Effect of Galactose on Growth and Metabolism of Avena Coleoptile Sections.

Methyl Esterification of Cell Wall Constituents under the Influence of Auxin.

The Formation of Starch and the Behavior of Isocitric Acid in Excised Leaves of Bryophyllum calycinum Cultured in Darkness

Absorption and Translocation of 2,4-Dichlorophenoxyacetic Acid and P³² by Leaves

Growth in Vitro of Marigold and Tobacco Tissue with Nucleic Acids and Related Compounds

News and Notes

Change of Editor-in-Chief

The Role of Cell Sap Concentration in Frost Hardiness

Altering the Pigments Produced by Tyrosinase and Ortho-Hydroxyphenols with a Meta-Hydroxyphenol, 4-Chlororesorcinol

The Effect of 2,4-Dichlorophenoxyacetic Acid on the Accumulation of Mineral Elements in Tobacco Plants

A Darkroom Safelight for Research in Plant Physiology