SPECIAL EXERCISES ON TYPICAL FLOWERS 199 



Describe each circle. (When the two outer circles are 

 alike in color, they are spoken of as a perianth instead of calyx 

 and corolla.) Of how many parts is the perianth composed? 

 How do these parts differ in position? In other respects? 

 What appendages are found on one set which are not found 

 on the other? Can you suggest any use for this? Note 

 the long, slender tube where the parts of the perianth are 

 united. Draw the flower. 



Remove the perianth and study the essential organs. 

 Draw. How are the stamens placed relative to the stigmas? 

 Is self-pollination possible in such a flower? Reason. 

 Where is the nectar secreted? Try to discover how pollen 

 can be transferred by bees from flower to flower. Where 

 is the ovary? Cut a flower lengthwise through the center. 

 Draw the section exposed. 



172. EVENING PRIMROSE 



Evening primrose may be found in dry fields, roadsides, 

 and waste places, and sometimes in gardens. It opens late 

 in afternoon about sunset and remains open all night, closing 

 next day about ten o'clock A.M. or earlier. It often remains 

 open longer if the day be cloudy. When opening, it often 

 makes a distinct sound like an explosion. 



Its fragrance is peculiar, having a suggestion of black 

 pepper. 



Method (Laboratory) . Are the flowers solitary or in clus- 

 ters? If clustered, describe the cluster. Remove one flower. 

 Has it a stalk (pedicel)? If so, describe it. Describe this 

 flower, calyx, corolla, stamens, pistils, giving number, size, 

 shape, character of the pollen, and other characteristics. 



Where do the old flowers grow? The buds? Can you 

 determine how many flowers will be borne on this cluster ? 



