INTRODUCTORY LESSONS. 



Xiii 



-I 



15 



17 



15. Germinating corn. 16. Wheat. 17. Wild- 



in paragraph 6 do not clearly show 

 their embryos in germination, but they 

 are readily enough distinguished from 

 dicotyledons. The downward growing 

 sprouts are several instead of one, and 

 the upward growing sprout is like a 

 rolled grass leaf (Figs. 15 to 17). By 

 tasting of the growing seeds you can 

 discover what the starchy albumen is 

 changed to before it is fit food for the 

 young plant. It must be remembered 

 that only the grass-like monoctyledons 

 grow as here represented. If possible, 

 get Lily seeds, Iris seeds, etc. 



If you examine seeds and study 



j, ,-. i , ,. . , oats ; o, colorless sheath inclosing the first plu- 



their growth as you have been directed, mule . leaf6 . c , the twisted and bent beard by 



you will hive the evidence of your Own means of which it is able to travel to cracks 



eyes that an embryo is a plant in a inthe gwmnd and thus plimt itself ' 

 sort of sleeping state from which it may be aroused to activity by moist- 

 ure and warmth. It will be evident that the radicle is a stem; that 

 the cotyledons correspond to leaves, and that the plumule is a bud 

 from which is to grow all the above-ground portion of the plant. Re- 

 member, that if these, or any other statements concerning the structure 

 and behavior of plants, are not confirmed by your own judgment upon 

 what you have yourself observed, they are useless to you, except as guides 

 pointing to what you are to find. To memorize these statements of facts 

 is to secure the husks, not the kernels, of knowledge. Plants themselves 

 must teach you how they grow. The book can only show you how to 

 question them and how to interpret their answers. Do not fail to care- 

 fully compare the results of all your experiments; for in this way you 

 can decide what are general or usual facts, and what are exceptional. 

 The latter should be closely investigated, since it is probable that there 

 is a reason for all unusual as well as usual behavior of plants. 



