Bulletin /

Title from cover.

Bulletin /

Title from cover.

McLean County soils /

Cover title.

Winnebago County soils /

Cover title.

Edgar County soils /

Cover title.

Du Page County soils /

Cover title.

Biennial report of the director /

Mode of access: Internet.

Circular /

None published, 1891-1914.

Bulletin /

Mode of access: Internet.

Annual report.

Imprint varies.

Bulletin.

Title from cover.

Bulletin /

Title varies slightly.

Circular bulletin.

Mode of access: Internet.

Special bulletin.

Size varies.

An experimental study of the rest period in plants.

"Second report"--T.p.