Vol. 13 No. 1-16 (1921)
Article 1 - The North American Species of the Genus Tiphia (Hymenoptera, Aculeata) in the Collection of the Illinois State Natural History Survey. J. R. Malloch
Article 2 - Ways and Means of Measuring the Dangers of Pollution to Fisheries. Victor E. Shelford
Article 3 - A New North American Oligochaete of the Genus Haplotaxis. Frank Smith
Article 4 - A Representative of the Genus Trichodrilus from Illinois. James E. Kindred
Article 5 - Contributions to a Knowledge of the Natural Enemies of Phyllophaga. John J. Davis
Article 6 - Some Recent Changes in Illinois River Biology. Stephen A. Forbes, Robert Earle Richardson
Article 7 - The Pentatomoidea of Illinois with Keys to the Nearctic Genera. Charles Arthur Hart
Article 8 - Acanthocephala from the Illinois River, with Descriptions of Species and a Synopsis of the Family Neoechinorhynchidae. H. J. Van Cleave
Article 9 - Foot-rot Disease of Wheat- Historical and Bibliographic. F. L. Stevens
Article 10 - The European Corn-borer and Some Similar Native Insects. Wesley P. Flint, John R. Malloch
Article 11 - A Study of the Malarial Mosquitoes of Southern Illinois I. Operations of 1918 and 1919.
Stewart C. Chandler
Article 12 - New Species and Varieties of Phyllophaga. John J. Davis
Article 13 - Further Tests of Dry Sulfur Compounds for the Control of the San Jose Scale. Wesley P. Flint
Article 14 - Forest Insects in Illinois I. The Subfamily Ochthiphilinae (Diptera, Family Agromyzidae). J. R. Malloch
Article 15 - The Small Bottom and Shore Fauna of the Middle and Lower Illinois River and its Connecting Lakes, Chillicothe to Grafton: its Valuation; its Sources of Food Supply; and its Relation to the Fishery. Robert E. Richardson
Article 16 - An Ecological Survey of the Prairie Vegetation of Illinois. Homer C. Sampson