Circulation of Hemolymph in the Wings of the Cockroach, Blattella germanica L. I. In Normal Wings. Stewart Clare and Oscar E. Tauber pages 107-128

Fungi Associated with Tree Cankers in Iowa. II. Diaporthe, Apioporthe, Cryptodiaporthe, Pseudovalsa and Their Related Conidial Forms. Joseph C. Gilman and G.L. McNew pages 129-154

Preliminary Studies on the Comparative Value of Some Sprays and Dusts in Potato Insect Control. H.C. Manis and Ila Leffert pages 155-162

Examination of Ice Cream with the Burri Smear Culture Technic. H.F. Long and B.W. Hammer pages 163-178

Preparation of an Active Juice from Bacteria. W.P. Wiggert, M. Silverman, M.F. Utter, and C.H. Werkman pages 179-186

Description of a Dexto-Lactic Acid Forming organism of the Genus Bacillus. A.A. Anderson and C.H. Werkman pages 187-194

Effect of Low Temperatures on the Intensity of Fluorescense. J.E. Dinger and William Kunerth pages 195-198

A Supplement to the Catalogue of Iowa Plants in the Iowa State College Herbarium. Ada Hayden pages 199-214