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FLOWERS 



arise from the top of a ring of tissue which surrounds the 

 ovary. This arrangement is called perigyny. (The word 

 signifies around the gynascium.) In the third arrangement 

 the tissue from which the other parts 

 arise grows right around the ovary so 

 that it forms the ovary wall; the other 

 parts appear to arise from the top of the 

 ovary itself. This arrangement is called 

 epigyny. (The word signifies upon the 

 gynoscium.) Of these three arrangements, 

 hypogyny is considered the most primi- 

 tive, and epigyny the most advanced. 

 Perigyny is somewhat intermediate; it 

 is commonly found in flowers of the great 

 rose family to which peach, pear, apple, 

 cherry, and plum belong. The great 

 majority of flowers, however, are either 

 distinctly hypogynous or distinctly epigy- 

 nous. An hypogynous flower is some- 

 times described as having a superior ovary, while the ex- 

 pression inferior ovary refers to epigyny. (See Figure 116.) 



Fig. 116. — A single 

 flower (magnified) 

 from the flowering 

 head of dandelion. 

 Note that the ovary- 

 is inferior {epigyny) , 

 all the other parts 

 of the flower arising 

 from above it. 



F. Variations in the Number of Parts. — A lily has 

 three sepals, three petals, six stamens, and three carpels. 

 An apple blossom has five sepals, five petals, an indefinite 

 number of stamens, and not more than five carpels. A 

 buttercup has five sepals, five petals, and an indefinite 

 number of both stamens and carpels. The flower of a 

 dandelion has a five-notched corolla, five stamens, and two 

 carpels. (What seems to be the flower of dandelion is 

 really a dense cluster of many small flowers.) 



As these examples show, the parts of flowers occur in 



