CHAPTER II. 



The Parts of the Seedling ; — its Development. 



16. Boot, Stem, and Leaf. — By the time the seedling is 

 well out of ground it, in most cases, possesses the three kinds 

 of vegetative organs, or parts essential to growth, of ordinary- 

 flowering plants, the root, stem, and leaf. All of these organs 

 may multiply and increase in size as the plant grows older, 

 and their mature structure will be studied in later chapters, 

 but some facts concerning them can best be learned by watch- 

 ing their growth from the outset. 



16. The Young Boot. — Eoots growing in sand or ordinary 

 soil cling to its particles so tenaciously that they cannot 

 easily be studied, and those grown in water have not quite 

 the same form as soil roots. Eoots grown in damp air are 

 best adapted for careful study. 



Experiment 6. In what Portions of the Boot does its Increase in 

 Length take Place f — Sprout some peas on moist blotting-paper in a 

 loosely covered tumbler. When the roots are one and a half inches 

 or more long, mark them along the whole length with little dots made 

 with a very small camel's-hair brush or a bristle dipped in water-proof 

 India ink. 



Transfer the plants to moist blotting-paper under a bell glass or a 

 battery jar and examine the roots at the end of twenty-four hours to see 

 along what portions their length has increased; continue observations on 

 them for several days. 



17. Boot-Hairs. — Barley, oats, wheat, or red clover seed 

 soaked and then sprouted on moist blotting-paper afford con- 

 venient material for studying root-hairs. The seeds may be 

 kept covered with a watch-glass or a clock-glass while sprout- 

 ing. A few of the red clover seeds should also be sprouted 

 in a deep cell on a microscope-slide. Examine those parts of 

 the root which have these appendages, first with the magnify- 



