Part 90. Terminology and nomenclature. Persons who have only a superficial acquaintance with botany are apt to think of it merely as a study of names, which hinder rather than help one in learning whatever botanists may know of general interest about plants. Doubtless the student of the foregoing chapters already feels that this is far from true; yet this false opinion conceals a truth which it will be worth while for us to consider.

Special names and descriptive expressions of various sorts do occupy a prominent place in the scientific study of plants, and these botanical technicalities doubtless present a more formidable appearance than the special terms of most other sciences. Yet, paradoxical as it may seem, the very fact that botanists use these means of expressing themselves, makes it much easier for a beginner to arrive at an understanding of what they have to say, and so to a knowledge of plants, than would otherwise be possible. The unusual fullness of their special vocabulary enables botanists to tell what they know in the fewest possible words and with least danger of being misunderstood. False ideas are the greatest hindrance to the pursuit of knowledge; and whatever will lessen the danger of these, especially to the beginner, is sure to save labor in the end.

We have already seen that the practice of having a double name for each species, instead of giving twice as much to remember as if the name of each sort were a single word, almost halves the burden upon one's memory that one-word names would impose. The ease with which words are remembered depends, as we know, largely upon how frequently the word is encountered; hence, the student is helped not a little by the circumstance that a large majority of specific names are the very words from which the descriptive terms in common use have been derived. Furthermore, these descriptive terms, as well as the names of the parts of plants and of genera and other groups, are in large part made up of a comparatively small number of Latin and Greek words, which once learned serve as helpful aids to the memory, and, indeed, often enable the student to tell at sight the meaning of a new botanical word.

In our study of systematic botany we shall learn the more important descriptive terms as we need them in developing a general idea of the natural classification of plants. The student will learn how to distinguish some of the more important families and higher groups, so that when he examines a plant he can tell at least the sub-kingdom to which it belongs, usually also the class, sometimes the order, often the family, and in certain cases even the genus and species. At first we shall confine our study to those plants which produce flowers and seeds, leaving for later consideration the groups including ferns, mosses, lichens, mushrooms, and seaweeds.