Abstracts of Doctoral Theses. pages 1-54

The Cyperaceae of Iowa. Charles L. Gilly pages 55-152

Studies on Oxygen-Carrying Cobalt Compounds: IV. The Reaction of Disalicylalethylenediimine and Cobalt Chloride Under Anhydrous Conditions. George C. Harrison and Harvey Diehl pages 311-315

Studies on Oxygen-Carrying Cobalt Compounds: V: Di-(2-Hydoxy-3Nitrobenzal)-Ethylenediimine Cobalt. 3-Nitro Co-Ox. Clifford C. Hach, Lawrence M. Liggett, and Harvey Diehl pages 316-325

Studies on Oxygen-Carrying Cobalt Compounds: VI. Di-(2-Hydroxy-3Methobenzal)-Ethylenediimine Cobalt. 3-Methoxy Co-Ox. Harvey Diehl and Lawrence M. Liggett pages 326-334

Studies on Oxygen-Carrying Cobalt Compounds: VII: Di-(2-Hydroxy-3Ethobenzal)-Ethylenediimine Cobalt and Higher 3-Alkoxy Analogues. 3-Ethoxy Co-Ox and Co-Ox ss. Harvey Diehl, Richard J. Brouns, Geroge C. Harrison, and Lawrence M. Liggett pages 335-350

Prolongment of the Reproductive Phase of Trypanosoma lewisi By The Administration of Sodium Salicylate. Elery R. Becker and Peggy L. Gallagher pages 351-362

Flora of Alaska and Adjacent Parts of Canada. VI. J.P. Anderson pages 363-423

The Effect of Panththenate Deficiency on Trypanosoma lewisi Infection in the Rat. Elery R. Becker, Jane Taylor, and Caroline Fuhrmeister pages 237-244

Curve-Fitting An Art or a Science? George W. Snedecor and George W. Brown pages 245-250

Oxidation of Polyhydric Alcohols by Acetobacter suboxydans. E.I. Fulmer and L.A. Underkolfer pages 251-270

Studies on Oxygen-Carrying Cobalt Compounds: I. Oxygen-Carrying Metallo-Organic Compounds. Their Use in the Manufacturing of Oxygen. Harvey Diehl pages 271-277

II. The Methods of Preparing Bi-(Disalicylalethylenediimine)-u-aquo-dicobalt, co-ox. Harvey Diehl, Clifford C. Hach, George C. Harrison, and Lawrence M. Ligget pages 278-286

III. The Composition and Chemical Properties of Bi-(Disaliclalethylenediimine)-u-aquo-dicobalt, co-ox. Harvey Diehl, Clifford C. Hach. George C. Harrison, Lawrence M. Liggett, and Tsai S. Chao pages 287-311

Seed Characters of Alfalfa and Certain Other Species of Medicago. Duane Isley pages 153-160

The Types of Auchenorrhynchous Homoptera in the Iowa State College Collection. P.W. Omen pages 161-228

Apocynum in Iowa. Margaret R. Murley pages 229-236