This book is not intended for the expert botanist. He should consult oneof the regular Manuals which give full descriptions of each species ofplant.
Neither is it intended for the merely curious. Only those who havesufficient interest in a plant to observe it can find its name by thisbook.
Furthermore, it is not a textbook. It does not attempt to conveybotanical information, but offers merely an opportunity to learn thenames of plants.
Its mission is fully accomplished if, through its use, students,vacationists, and plant-lovers in general are able to recognize by namethe plants about them.
One recognizes a plant by the presence of structural features peculiarto itself, and not found on any other kind of plant. In such a book asthis, these characters are given one or a few at a time, and contrastedwith the characters which other sorts of plants possess. Such apresentation is called a Key, and by its proper use the name may belearned of any plant considered in it. This process is calledIdentification.
Keys are constructed in several different ways, although the principleof all is the same. In this book, the user will begin with lines 1a and1b on the page headed Key to the Groups. Each of these lines includessome descriptive matter, but only one of them can apply to the plantbeing identified. For example, if the plant to be identified is an Oak,line 1a will apply perfectly, and the same line will also apply to anyother kind of tree or to any shrub. But if the plant is a Violet, aButtercup, or any other herb, line 1b agrees and line 1a will not apply.At the end of each line is a reference to be consulted next. If theplant is a tree or shrub, one turns accordingly to Group 1, on page ix,and begins again at the first number given. If the plant is an herb, hefollows the reference to line 2, just below, and again compares theplants with lines 2a and 2b.
Under every number at least two lines of description are given,designated a and b, and under a few numbers additional lines appear,designated c, d, etc. In every case, the user of the key will selectfrom the different lines under the same number that particular linewhich agrees with the structure of the plant, and follow up thereference given at the end of that line. Eventually one finds at the endof a line, instead of a number, the name of a family of plants, to whichthis particular plant belongs, and then turns over to the page wherethis family is treated. Under each family is a similar key, to befollowed in exactly the same way, until finally one finds instead of anumber the common name and the scientific name of the plant in hand. Theprocess of identification is now completed, and the student has foundthe name of the plant.
In some cases, a reference is made in the key to a particular portion ofthe family key. One then turns directly to this particular number in thefamily key, and continues his identification in the usual way.
As a definite example of the use of the