PREFACE Vii 



Chapters XXXIV and XXXV, on the Gymnosperms and 

 Angiosperms, as well as the latter portions of the chapters on 

 the algae, fungi, mosses and ferns, are not intended for study 

 except in advanced classes. Some few students, however, will 

 be interested in the life histories, with the illustrative formulae 

 and graphic representations of life cycles, together with the 

 reviews showing progression in the evolution of plant struc- 

 tures. The author believes it is a good principle in pedagogy 

 to present now and then ideas and inferences upon the work 

 which may be beyond the comprehension of the majority of 

 the members of the class, of course without holding the stu- 

 dents answerable in any way for it. It is stimulating and sug- 

 gestive to most students especially if it is not required work, 

 and serves now and then to lift their minds out of the ''hum- 

 drum" of the regular course. A few will catch glimpses of 

 principles and processes in nature which will be decidedly 

 beneficial in the development of thought and reasoning power. 



Since it is neither practicable nor desirable to lay down a 

 hard and fast course for all high schools, there are suggested 

 below several courses \vhich are suitable for different con- 

 ditions. 



For short courses, one half year or less: Part I, and Chapter 

 XXXVI (Economic or Useful Plants) with parts of Chapters 

 XXXVII, XXXVIII and XXXIX. For a full half-year course 

 the study of an alga (Spirogyra), a mold (Bread mold), a moss 

 (Polytrichum or other type) and a fern may be added. 



For courses in agricultural botany: Part I, and Chapters 

 XXVI-XXIX (Fungi), Chapter XXXVI (Economic or Use- 

 ful Plants), and parts of Chapters XXXVII, XXXVIII and 

 XXXIX. 



For two half-year courses: First course: Part I, and Chapter 

 XXXVI (Economic or Useful Plants) and parts of Chapters 

 XXXVII, XXXVIII and XXXIX. Second course: Chapters 

 XXII-XXXV. Several algae and fungi, a lichen, a liverw r ort 

 and moss (with a few additional types for illustration), a fern 

 (with several additional ones, with horsetails, club-mosses and 



