Plants should be mounted on paper 16¼ × 11½ inches
A few facts should accompany each plant to refresh your memory of that specimen when you come to study it later. These facts should have been recorded by you in whatever way you like and referred to the specimen by a number while in the press. Finally each mounted specimen should have its label, bearing the name of the plant, the collector's name, the date collected, locality, and any useful information regarding it. Glue the label into the lower right-hand corner, which should always be reserved for that purpose.
These loose sheets, covered with mounted specimens, must not be allowed to lie in a shelf or drawer unprotected. Each group of them should be put into a folded sheet of manilla paper. Such a holder is called a "genus cover." Its size, folded, is eleven and three fourths by sixteen and one half inches.
This word "genus" suggests that in time the collector is going to be able so to classify his specimens that each genus cover may contain only plants so closely related one to another that they are of the same botanical genus. The beginner need not be seriously disturbed if there are many plants in his collection that he does not know the names of yet. The collection is for study or it is worth nothing. Knowing plants is more important than knowing names. You cannot handle plants much and observe them in their places without noticing how different they are. Then you begin to see that some are more like than others. This is the beginning of classification. You need not know even the common names of the plants to do this, although you will know some, of course. Professor Bailey says: "Learn first to classify plants; names will follow. Look for resemblances, and group plants round some well-known kind. Look for sunflower-like plants, lily-like, rose-like, mint-like, mustard-like, pea-like, carrot-like plants. These great groups are families."
After you have handled your common plants a good deal you will be surprised to find how easily you can guess at one's family, and guess right.
When you have reached this stage in your collecting you will feel that you need some book to guide you and act as a check on your studies. All the books mentioned in the lists in this book are useful for beginners. If you find a book which pretends to take the place of the plants themselves, you would better throw your money away than buy it. Instead of helping it will hinder your progress. You will find in beginners' botanies what is known as a "key." Now, a key is obviously to unlock something with. If you had a door key which turned with difficulty, or fitted the lock imperfectly you would be sure to have it repaired or get a more modern one. Some of the old botanical keys seem to be rusty and it is difficult to use them. Choose the key that works most easily.
In making a key for classifying plants one begins by dividing the whole vegetable kingdom into two big departments, thus:
A. Plants which never have flowers.
AA. Plants which do have flowers.
As your specimens are all of the flowering kind we shall for the present forget all about the others and begin to divide our big group AA into smaller groups. This is how it is done: