VI PREFACE 



primary purpose of plant analysis leading to the naming of 

 plants, but in order to stimulate the student to recognize some 

 of the general facts indicating the bond which unites the 

 very diverse elements of the natural world. This should be 

 one of the chief aims in all studies of nature, not because it 

 is the scientific method, but because of the unconscious and 

 wholesome influence which it has upon the formation of char- 

 acter and the development of a taste for the things beautiful 

 in nature, in art, and in life's best work. 



Several chapters are devoted to a study of the peculiar and 

 unusual forms of nutrition by certain plants that have become 

 closely associated in this respect with other organisms, and by 

 the fungi and bacteria, which, lacking chlorophyll, must obtain 

 certain food by other means than that employed by the green 

 plants. In this connection special attention is given to some of 

 the more important micro-organisms which are beneficial to 

 man because of certain products of their activity, or which are 

 harmful as causal agents in disease. One chapter is devoted 

 to the study of the more useful plants of the farm, orchard 

 and garden or of those employed in industrial operations. 

 Chapters are also devoted to the principles of plant develop- 

 ment and plant breeding, subjects which are of absorbing inter- 

 est to all and of special practical importance to the farmer and 

 horticulturist. 



In schools where attention can be given to a study of rep- 

 resentative plants in the different branches of the Plant 

 Kingdom (in most schools at least a few can be studied) the 

 chapters on the algae, fungi, mosses and ferns will furnish the 

 material and outline. Footnotes at the beginning of these 

 chapters suggest one or two plants in each group which can be 

 studied where there is not time for all. In these chapters 

 several more plants are treated than can under ordinary cir- 

 cumstances be studied in the high-school course. Their inclu- 

 sion in the book, however, aids in rounding out the subject, and 

 in most cases they will serve a purpose for special assignment 

 for reading, or for reference or for illustration. 



