THE TYPICAL LEAF AND ITS PARTS 2^ 



various substances required by the different tissues before 

 it can be appropriated by them. 



PRACTICAL QUESTIOKS 



1. Why do gardeners bank up celery to bleach it ? (25.) 



2. Why are the buds that sprout on potatoes in the cellar white? (25.) 



3. Why does young cotton look so pale and sickly in long-continued 

 wet or cloudy weather ? (25.) 



4. Why do parasitic plants generally have either no leaves or very 

 small, scalelike ones ? (25.) 



5. The mistletoe is an exception to this ; can you tell why ? (184.) 



6. Could an ordinary self-supporting plant live without green 

 leaves ? (26, 27.) 



7. Are abundance and color of foliage any indication of the health 

 of a plant ? (24, 26.) 



8. Is the practice of lopping and pruning very closely, as in the 

 process called " iJoUarding," beneficial to a tree under ordinary con- 

 ditions ? (18, 21, 24, 26.) 



9. Why is it wise to trim a tree close when we transplant it ? 

 (20, 21.) 



10. Why should transplanting be done in winter or very early spring, 

 when the leaves are off ? ( [9, 20.) 



11. Name some plants of your neighborhood that grow well in the 

 shade. 



12. Compare in this respect Bermuda grass and Kentucky blue 

 grass ; cotton and maize ; horse nettle {Solanum carolinense) and 

 dandelion ; beech, oak, red maple, dogwood, pine, cedar, holly, mag- 

 nolia, etc. 



13. Why are evergreens more abundant in cold than in warm 

 climates ? (19, exp.) 



14. Is it wholesome to keep blooming plants in a bedroom ? Leafy 

 ones ? 



15. Why, in each case ? (23, 28.) 



THE TYPICAL LEAF AND ITS PARTS 



Material. — Leaves of as many different kinds as can conveniently 

 be obtained, showing their various modes of attachment, shapes, tex- 

 ture, etc. For stipules, leaves on very young twigs should be sought 

 for, as these bodies often fall away soon after the leaves expand. The 

 rose, Japan quince {Pyrus japonica), willow, strawberry, jjansy, pea, and 

 young leaves of apple, peach, elm, oak, beech, tulip tree {Liriodendron), 

 India rubber tree {Ficiis elastica), magnolia, etc., furnish good exam- 

 ples of stipules. 



