This addition to the fonds consists of articles and booklets written by Frank Morris; manuscripts and published articles by Douglas Sadler; correspondence, minutes of meetings relating to Sadler's involvement in environmental and naturalist issues and activities; correspondence relating to Teacher's College and several issues of the Young Naturalist. Fonds is arranged into 6 series:

• Frank Morris: published and unpublished articles, reviews, etc.
• Douglas Sadler: published and unpublished articles, manuscripts, reviews, research material, etc.
• Naturalist/environmental involvements with business organizations, government, etc.
• The Young Naturalist
• Correspondence
• Personal materials

This addition to the fonds consists of field naturalist newsletters and journals from across Ontario, with many of the publications including illustrations. Also included in the fonds are numerous bird spotting forms and error forms for the Ontario breeding bird atlas.