This journal provides immediate access to some articles. Volume 15(2); April 1940 Articles FACTORS AFFECTING REGENERATION OF THE HORSERADISH ROOT PMCID: PMC437799 THE ABSORPTION OF CARBON DIOXIDE BY UNILLUMINATED LEAVES PMCID: PMC437800 DISTRIBUTION OF NITROGENOUS AND CARBOHYDRATE FRACTIONS AND OTHER SUBSTANCES IN EXPOSED AND COVERED PINEAPPLE SISTER SHOOTS PMCID: PMC437801 RESPIRATION OF CEREAL GRAINS AND FLAXSEED PMCID: PMC437802 EFFECT OF LIGHT INTENSITY ON THE DEVELOPMENT OF THE PHOTOSYNTHETIC MECHANISM PMCID: PMC437803 AUXIN IN MARINE ALGAE PMCID: PMC437804 SPIRAL SYSTEMS IN THE ORGANIZATION OF LIVING MATERIAL PMCID: PMC437805 RELATION BETWEEN QUANTITY OF CHLOROPHYLL AND CAPACITY FOR PHOTOSYNTHESIS PMCID: PMC437806 EXPERIMENTS ON PHOTOPERIOD IN RELATION TO THE VEGETATIVE GROWTH OF PLANTS PMCID: PMC437808 OBSERVATIONS ON THE DEVELOPMENT OF CERTAIN CELL-WALL CONSTITUENTS OF FORAGE PLANTS PMCID: PMC437810 SOIL TEMPERATURE AND GROWTH OF MARQUIS WHEAT PMCID: PMC437812 EFFECT OF CERTAIN THIOCYANATE SPRAYS ON FOLIAGE AND FRUIT IN APPLES PMCID: PMC437814 DOES “C.P. GRADE” SUCROSE CONTAIN IMPURITIES SIGNIFICANT FOR THE NUTRITION OF EXCISED TOMATO ROOTS? PMCID: PMC437816 Brief Papers: SUCROSE VS. DEXTROSE AS CARBOHYDRATE SOURCE FOR EXCISED TOMATO ROOTS PMCID: PMC437817 KUNDT'S RULE PMCID: PMC437818 Note NOTES PMCID: PMC437819 Journal Matter Original table of contents page Administrative content — journal masthead, notices, indexes, etc. | ||