98 



SCIENCE. 



[N. S. Vol. IX. No. 312. 



liow great and in what direction the change 

 is. Chief of the several causes of the ad- 

 vance is this : University and college teach- 

 ers, imbued with the newer and broader 

 spirit, are taking an interest in the ele- 

 mentary teaching of their subject not only 

 in their own colleges, but also in the schools. 

 If we consider the elementary text-books of 

 approved standing and widest use in this 

 country that have appeared within the past 

 three years, those by Spalding, Bergen, 

 Strasburger, Vines, Setchell, Curtis, L. H. 

 Bailey, Barnes and Atkinson, we find that 

 with but one exception, they are by uni- 

 versity or college teachers. It is, of course, 

 but presumption for anj' college teacher to 

 attempt to instruct a school teacher in 

 methods of imparting knowledge to school 

 children ; but the college teacher, with his 

 broader horizon, larger command of the 

 sources of knowledge, and better facilities 

 for experiment, can best set forth what the 

 science has to offer to education, and the 

 most useful proportioning and ti'eatment of 

 topics. The new school teacher can be 

 trusted to take care of his own methods. 

 This is the spirit of the newer books ; they 

 do not seek to impose any system upon 

 teacher or student, but are storehouses of 

 knowledge and advice to be drawn upon by 

 all according to their needs. 



We turn next to a summary of advances 

 actually being made in elementary botan- 

 ical teaching, and of tendencies likelj' to be 

 of importance in the near future. I need 

 hardly speak of the continuous spread of 

 laboratory and decline of rote instruction ; 

 happily this is now a matter of course. Aside 

 from this, the first and greatest of current 

 advances is the shifting of the point of view 

 from the static to the dynamic side of the 

 plant, entailing a great increase of attention 

 to phj'siology and ecology. We are ceasing 

 to look upon the plant as, first of all, a drue- 

 ture to whose parts certain functions attach, 

 and are beginning to see it as a living thing 



whose functions determine its structure, 

 a working, struggling organism, plastic, 

 though with an hereditary stiffness, to out- 

 side influences, not striving to realize some 

 ideal plan, but simply to fit itself to the 

 conditions that exist. Thus the leaf, from 

 one point of view a structure of such a 

 shape, size, venation, cellular composition, 

 etc., carrying on the work of photosynthe- 

 sis, is from another a mechanism so built 

 as to expose a large amount of green tissue 

 to light and to protect, support, supply and 

 aerate it, and any given leaf is a resultant 

 of the working of all these factors upon it, 

 and as any one of them varies with the 

 external influences so does the leaf var}-. 

 N"ow the clue to this view of the leaf lies in 

 the necessity for light in the formation of 

 starch, the food and sole source of energy 

 of the plant, and this can be appreciated by 

 a student only after experiment upon the 

 relation of light to starch formation, ex- 

 periment that happily is very easy and 

 every where practicable. Thus approached, 

 leaf-structure becomes luminous. In the 

 same way it is absorption of liquids by 

 osmosis that explains the root, and the re- 

 sultant between the physical requirements 

 of this osmosis and the varying external 

 conditions under which roots are forced to 

 grow, explains why a given root is the form, 

 size and texture it is. Again, it is observa- 

 tion of modes of locomotion of pollen in 

 eifecting cross-fertilization, and secondary 

 conditions connected therewith that explain 

 the flower, and so on. Experience is show- 

 ing that the only road to an objective un- 

 derstanding of anatomy and morphology 

 lies through physiology and ecology. And 

 this conception of the plant, as a living, 

 working, struggling, plastic being is not 

 only the truest, the most objective concep- 

 tion of it, but is, as well, the one that ex- 

 cites the greatest human sympathy and in- 

 terest, and, therefore, is in itself the best 

 ' method ' the science has to offer. 



