84 LABORATORY PRACTICE CHAP, xvm 



IV. Such a pistil is called a simple pistil because it has 

 only one stigma, one style, one ovary, one cell to the ovary, 

 and one placenta. (Any pistil having more than one style 

 stigma, ovary-cell, or placenta, is called a compound pistil. 

 Compound pistils are more common than simple ones.) 



V. Pick off all the parts of the flower in regular order, 

 beginning with the sepals. The small conical tip of the stem 

 upon which they are inserted is called the receptacle. 



VI. This flower is an example of a perfect, complete, reg- 

 ular, and symmetrical flower. 



1. It is perfect because it has both stamens and pistils. 



2. It is complete because it has all the organs possible for a 



flower to have : viz. sepals, petals, stamens, and 

 pistils. (A complete flower must necessarily be 

 perfect.) 



3. It is regular because in each circle all the parts are of 



the same size and shape (i.e. without any striking dif- 

 ferences) . 



4. It is symmetrical because each circle contains the same 



number of parts as each other circle. 



VII. Alternation of the Parts of the Flower. Take an 

 uninjured flower and notice : 



1. Whether the petals are in front of the sepals or in front 



of the spaces between the sepals. 



2. Does the same thing hold true for the stamens in relation 



to the petals ? 



3. For the pistils in relation to the stamens? 



4. This is called the alternation of the parts of the flower 



and is true for the parts of most flowers. 



