54 NATURE TP^ACHING 



youngest leaves in both cases, and observe how this 

 apparent great difference in the arrangement of the 

 leaves is brought about. 



Fasten one of the horizontal shoots, without damaging 

 it in any way, so that it is upside down, and see how the 

 young leaves arrange themselves. 



Examine also shoots of hazel nut, ivy, horse chestnut, 

 maple, creeping jenny, and learn that in all these cases 

 leaves are arranged on the stems so that they may be 

 well exposed to the light, and do not shade one another. 

 Make drawings of these leaf arrangements. 



Uses of Stems. 



Dig up a growing plant of iris or flag, wash it free 

 from soil, and notice the underground stem with its well- 

 marked rings. Examine the youngest part, and notice 

 the sheathing bases of the green leaves. Pull a leaf off 

 and see the scar it leaves. What have these scars to do 

 with the rings seen all along the stem ? Look for leaf- 

 buds along the stem, and ascertain how the stem 

 branches, and how new plants may be formed. Make 

 sketches showing all the parts seen, including the grow- 

 ing portion, the leaf-scars, the buds, and the roots. 



Examine " Jerusalem " artichokes, noting the large 

 number of slightly projecting scale leaves with which 

 they are covered. If possible, obtain a whole plant as 

 dug up, carefully wash away the soil, and see that the 

 artichokes are borne on very short underground stems 

 which are quite distinct from the roots of the plant. 



Make drawings of the whole clump, and of one 

 separate artichoke, 



