THE COMPOSITE FAMILY. 237 



1. The seed-like ovary, its form and surface, and the 



prolongation of its upper end into a short beak, 

 which afterwards becomes greatly elongated. 



2. The calyx, with its limb of numerous fine bristles, 



pappus. 



3. The yellow, ligulate corolla. 



4. The stamens inserted on the corolla, epipetalous, 



with their anthers united in a hollow cylinder 

 around the style, syngenesious, the latter soon pro- 

 jecting beyond them and divided above into two 

 slender, recurved, and finally coiled branches. 

 (Specimens should be gathered in the morning 

 and also in the afternoon.) 



II. Compare successively older, outer flowers with the 

 younger ones, approaching finally the unopened flowers at 

 the center. Note the different stages of development of 

 the flower, particularly of the stamens and pistil. Observe 



1. The way the pollen is pushed out by the style. 



2. The short, stiff hairs on the outer surface of the 



latter. 



3. The papillae on the inner, stigmatic surface of each 



of its branches. (These latter require higher 

 magnification in order to be seen clearly.) 



III. Imitate the action of a bee or other insect by 

 repeatedly brushing a large number of flowers. Examine 

 the stigma before and after the operation. Is there any- 

 thing to favor cross-fertilization ? 



Fruit. 



Study next a head in fruit. Compare the hard, seed- 

 like achenium with the immature ovary already examined 

 and note differences . What arrangements are there for 

 the dissemination of the fruits ? 



