Age and growth of channel catfish from the Des Moines River, Boone County, Iowa, 1955 and 1956. R. Jess Muncy. 127

A quantitative deterioration rating scale for shelled corn. R.W. Lightwardt and G.L. Barron. 139

Quantitative estimations of the fungi associated with deterioration of stored corn in Iowa. G.L. Barron and R.W. Lightwardt. 147

The effect of some organic compounds on the rate of the Fe(II)-Fe(III) exchange. Frederick R. Duke and Edward Wolf. 157

Some reactions of gelsemine. Ernest Wenkert and John H. Hansen. 163

Index to Masters' Theses. 1957-1959. 175

Index to Doctoral Dissertations, 1958-1959. 187

Iowa State University Staff Publications List, 1958-1959. 193