Part 1 covers vascular cryptogams, often referred to as "ferns and fern allies"; gymnosperms; and monocotyledons. An unusual feature is the inclusion of a key to the species of grasses based upon vegetative features, as well as one to grass genera based primarily upon floral structures. Part 1 also includes several sections relating to the work as a whole: an Index to Plant Families, a Glossary, a key to aquatic plants based mainly on vegetative features, several pages of additions and corrections, and a general index to common, generic, and specific names.
Illustrated by Jeanne R. Janish.