INTRODUCTIOX. 



To the student we would say that they, as men fitting them- 

 selves for professional or semi-professional scientific careers, have 

 certain duties to themselves, entirely independent of the formal 

 requirements of the instructor. Their aim should be a complete 

 familiarity with the methods suggested, a comprehensive and scien- 

 tific knowledge of as many facts as possible, and an ability not only 

 to execute but to finally plan their own work, and themselves solve 

 their scientific problems. To this end they should not, even in this 

 elementary course, content themselves with the lines laid down, 

 but should consult all books suggested in the studies given in the 

 manual, and read carefully the passages to which reference is 

 made. They should miss no opportunity to learn of a new work 

 or an original paper in botany, or any fact concerning the mode of 

 work of any genuine contributor to the literature of the science. 

 We have an especial sympathy with the ambitious student whose 

 superior training or skill enables him to accomplish more than the 

 average students. For him are suggested the additional studies in 

 the hand-book, and he will always find his instructor ready to advise 

 him in regard to further reading. Both teacher and pupil should 

 recognize the fact that in the present day, a sure foundation may 

 be laid in undergraduate years, for a subsequent successful profes- 

 sional career, if the pupil thoroughly learns the use of his tools 

 and pursues his chosen science with the zeal that belongs to his 

 time of life. 



It is with genuine regret that I lay down this work as well as 

 the particular plans which were the motive of it, for broadening 

 and deepening the training of American botanical students; but in 

 doing so, I am sure that in the hands of Professor Thomas it will 

 arrive at a better development than in my own, and that his efforts 

 in this field will find nothing but appreciation. 



The authors wish to express their indebtedness to Mr. E. W. 

 Olive, Instructor in Biology in Wabash College, for the many ways 

 in which his services have lightened the labors in the prepai'ation 

 of this manual. 



WILLIAM RUSSEL DUDLEY, 



August, 1894. Leland Standford. Jr., University. 



