Vol. 4 No. 1-15 (1897)
Article 1 - Bacteria Normal to Digestive Organs of Hemiptera. S. A. Forbes
Article 2 - Descriptions of two New Deltoid Moths. G. H. French
Article 3 - The Life History and Distribution of the Prothonotary Warbler in Illinois. W. E. Loucks
Article 4 - List of Altitudes in the State of Illinois. C. W. Rolfe
Article 5 - A Preliminary Account of two New Oligochaeta from Illinois. Frank Smith
Article 6 - On the Entomology of the Illinois River and Adjacent Waters. C. A. Hart
Article 7 - Descriptions of three New Parasitic Hymenoptera from the Illinois River. William H. Ashmead
Article 8 - Notes on Species of North American Oligochaeta. Frank Smith
Article 9 - Some Notes on the Brain and Pineal Structures of Polyodon folium. H. Garman
Article 10 - Descriptions of New Species of Rotifera and Protozoa from the Illinois River and Adjacent Waters. Adolph Hempel
Article 11 - A Check-list of the Coccidae. T. D. A. Cockerell
Article 12 - On a Bacterial Disease of the Squash-bug (Anasa tristis DeG.). B. M. Duggar
Article 13 - Descriptions of five New Species of Scale Insects, with Notes. Willis Grant Johnson
Article 14 - Notes on Species of North American Oligochaeta. II. Frank Smith
Article 15 - Contribution to a Knowledge of the North American Fresh-water Ostracoda Included in the Families Cytheridae and Cyprididae. Richard W. Sharpe