Wherever the terms used are not understood, reference should be made to the "Explanation of Terms" or to the Glossary.
For identification of species not found in the present work, other books should be consulted. The two large volumes of the botany of the Geological Survey of California are the most complete of anything thus far published. In addition to these, "The Synoptical Flora of North America," as far as published (the Gamopetalæ, the Compositæ, and some orders of the Polypetalæ), furnishes valuable aid. Professor E.L. Greene's works, "The Botany of the Bay Region," "Pittonia," and "Flora Franciscana," furnish excellent plant-descriptions for the more advanced botanist. The author's technical descriptions have in every instance been verified by comparison with one or more of the above works.
Miss Eastwood's little volume, recently published as Part Second of "Bergen's Elements of Botany," (and also issued in separate form), is recommended for use in connection with the present work, as it embodies in compact form a general view of the method of classification of plants, showing their places in the plant-world and their relations to one another. It also contains very clear descriptions of plant-families. To the student who becomes interested in knowing more about the structure of plants, Gray's "Structural Botany" will prove useful; and the large work of Oliver and Kerner (translated from the German) will prove a fascinating book.
EXPLANATION OF TERMS
[The following simple definitions of the more common terms used have been mostly taken or adapted from the works of Asa Gray and others, and will prove useful to those unacquainted with botany, or to those whose memories require refreshing.]
ROOTS
The root is that portion of the plant which grows downward, fixing it to the soil, and absorbing nourishment from the latter. True roots produce nothing but root-branches or rootlets.
Simple or unbranched roots are named according to their shapes—
conical, when like the carrot;
napiform, when like the turnip;
fusiform, when like the long radish.