100 



LEAVES AND FOLIAGE 



Review. How may leaves be studied ? What is meant by func- 

 tion? What do leaves do? What other parts may perform the function 

 of leaves? How is form of leaves associated with 

 their function ? What are simple leaves ? Com- 

 pound? What is venation? What are the types or 

 kinds of venation? What are the two types of 

 compound leaves? What is a leaflet? Define bi- 

 compound ; decompound. What are lobed, cleft, 

 parted, and divided leaves? Pinnatifid leaf ? Com- 

 plete leaf? Complete leaflet? What is a sessile 

 leaf? How may the petiole join the blade? How 

 are the shapes of leaves named or classified? De- 

 fine the shapes described in 198. Describe com- 

 mon shapes of the base of the leaf. Of the apex. 

 Of the margin. How are the forms and sizes of 

 leaves ever related to theiplace in which they grow? Why do leaves 

 fall.? Define deciduous. Persistent. Evergreen. When do pine 

 leaves fall ? How can you distinguish leaves? Describe the leaf in 

 Fig. 146. 



146. Oblique leaf of 

 the elm. 



The same lilac bushes in January ami July. Framework and foliage. 



