NATURE-STUDY LESSONS. 131 



17. (a) Discover on which part of the tuber the buds 



are most vigorous. 

 ((5) Why are the buds more numerous at the outer 

 than at the inner end ? 



18. Compare these buds with those on stems growing 

 above ground. 



19. {a) Dissolve a few crystals of iodine in an ounce or 



two of water and add a drop to the freshly- 

 cut surface of a potato. 

 (d) Observe what takes place. 

 The color reaction (blue) is the test for the presence of starch. 



20. Why is the potato a valuable food ? 



21. At home try to discover the best method of 

 boiling potatoes. 



Try putting them into cold water and letting them cook, and putting 

 them into boiling water to cook, to discover the preferable mode. 



XXXIV.-GRASS. 



Wheat, oats, barley, rye, millet, rice, Indian-corn, foxtail, and chess are 

 grasses as well as timothy or red-top, but the plants usually thought of 

 when we speak of grass are those suited to the lawn, pasture or meadow, 

 except the clovers. 



1. (a) In a well-known little poem called "The Song 



of the Grass" the grass is represented as 

 singing, " I come creeping." What character 

 does grass possess that enables it to " come 

 creeping " ? 

 (d) Dig up grass plants and study them to find 

 where such power resides. 



2. (a) Observe pieces of land that have not been culti- 



vated for a year or two. 

 (S) Note the succession of plants — first, the erect 



weeds ; bye and bye, the grass. 

 (c) How is it that the slender, lowly grass can drive 



off the stout weeds ? 



