REPRODUCTION IN PLANTS 73 



3. The single white stalk with three divisions at the top 



is the upper part of the pistil. The dark green 

 body below the tubular part of the floral en- 

 velopes is the lower part of the pistil. 

 Is the top of the pistil in the flower you are studying 

 lower or higher than the stamens ? 



4. Make a drawing, natural size, of the side view of the 



flower, and label the following parts : the divided 

 portion of the floral envelopes, the tubular por- 

 tion of the floral envelopes, the stamens, the 

 pistil. 



B. Essential organs. The stamens and pistils are called 

 the essential organs of flowers because without 

 them the work of the flower cannot be performed. 



1. Carefully slit open the tubular part of the floral 



envelopes down to the lower part of the pistil. 

 Then remove the floral envelopes, leaving the 

 entire pistil uninjured. 



a. State what you have done. 



b. To what are the stamens attached ? 



c. The enlarged part at the top of the stamen is 



called the anther, the stalk-like part is called the 

 filament. Name and describe the parts of a 

 stamen. 



2. Make a drawing, natural size, of a portion of the floral 



envelope to which a stamen is attached. Label 

 division of floral envelopes, anther, filament. 



3. Find a flower the stamens of which have a powdery 



substance known as pollen. Which part of the 

 stamen produces the pollen ? 



4. The pistil consists of an enlarged portion at the base 



called the ovary, a stalk-like portion called the 

 style, and a spreading portion at the top, each 

 part of which is called a stigma. Name and 

 describe each part of the pistil. 



5. Make a drawing, natural size, of the pistil and label 



ovary, style, stigmas. 



6. Cut thin cross sections of a well-developed ovary, lay 



them on a dark-colored background, and study 

 one or more of them with a magnifier to make 



