6 FLOWERS 



entirely distinct, each one having its own carpels 3. This number is established in 



ovary, style, and stigma. For example, many families related to the lilies, and is 



in the buttercup there is a little mound in one of their characteristic features, 



the .center of the flower made up of nu- In other groups of flowering plants a 



merous pistils, each consisting of a single different number is established, the num- 



carpel. It is evident, therefore, that a ber five being the most common. For 



pistil may consist of one carpel or several example, in the common wild geranium 



carpels, and that in the latter case the the flower formula is as follows : sepals 5, 



carpels may be more or less completely petals 5, stamens 5 plus 5, carpels 5. In 



united. The sure indication of a carpel is still other flowers the number four is 



that each carpel bears its own ovules. established. 



In some flowers there is but a single In many common flowers it will be no- 

 carpel, as in peas and beans, whose pods ticed that no definite number is estab- 

 have developed from a pistil consisting^ lished, or that it is not completely estab- 

 a single carpel, as is indicated by the sin- lished. For example, in the common wild 

 gle lengthwise set of seeds. rose there are 5 sepals and 5 petals, but 



In some plants the flowers do not have an indefinite number of stamens and car- 

 all the four parts described above. In pels ; while in the water lily there is no 

 some cases the petals may be lacking, the definite number established, the sepals 

 one set of perianth parts represented be- being usually 4, and the other parts in- 

 ing regarded as the calyx, although it definitely repeated. 



may look like a corolla, as in the clematis In those flowers in which some num- 



or anemone. Such flowers are said to be ber is definitely established, it often hap- 



apetalous, which means "without petals/' pens that one set may be reduced in 



In other cases both the calyx and corolla number, and this is usually the carpel set. 



may be wanting, the flower consisting of In the families of highest rank among 



only stamens and carpels. Such flowers flowering plants, such as the figworts, 



are spoken of as naked. mints, and composites (sunflowers, 



In other flowers the stamens may be asters, dandelions, etc.) the flower for- 



lacking, and as the pistil is the only es- mula is sepals 5, petals 5, stamens 5, and 



sential part present such flowers are said carpels 2. 



to be pistillate. It may be counted upon, Another fact shown by the lily flower 



however, that if there are pistillate is that the different sets alternate with 



flowers there are also corresponding each other in position. The three petals 



staminate flowers in which the pistils are do not stand directly in front of the three 



lacking and the stamens present. In such sepals, but in front of the spaces between 



cases both staminate and pistillate flowers the sepals. In the same way the three 



may occur on the same plant, or they may outer stamens alternate with the petals ; 



occur on different plants, so that there the inner stamens alternate with the outer 



may be not only staminate and pistillate ones ; and the three carpels alternate with 



flowers, but also staminate and pistillate the inner set of stamens. It is very un- 



plants. common to find one set standing directlv 



It also sometimes happens that stami- in front of the next outer set, and this 



nate and pistillate flowers are also naked, position opposite the other set always 



so that in such cases the flower is repre- needs some special explanation. As a 



sented by stamens alone, or even by a rule, therefore, the flower sets alternate 



single stamen, or by carpels alone, or by with one another, but in some cases a set 



a single carpel. It would be hard to may be opposite. 



imagine a more simple flower than one The history of a flower does not end 



composed of a single stamen or a single with the opening of the blossom. If the 



carpel. Such flowers may be found in stigma has succeeded in receiving some 



the willows. pollen, and the pollen has succeeded in 



In this study of the lily it should be ob- doing its work, the ovules within the 

 served that the number three runs ovary become gradually transformed into 

 through all the parts of the flower. The seeds, and the ovary becomes trans- 

 flower formula may be expressed as fol- formed into the fruit, the outer sets of the 

 lows : sepals 3, petals 3, stamens 3 plus 3, flower usually disappearing. In the lily 



