204 APPLIED BIOLOGY 



four, or five) ; but many other flowers vary as to the number 

 of these parts. 



There is no essential relation between number of parts 

 and the reproductive function of flowers. Three sepals in 

 one flower may inclose the flower bud as well as five or 

 more do in some other flower ; a few petals which are large 

 and conspicuous may be more useful in relation to insects 

 than are many small petals ; a few stamens may be large and 

 produce more pollen than numerous stamens; and there is 



s r e 



FIG. 63. Relation of the ovary and receptacle in flowers, r, receptacle ; 

 o, ovary. (From Strasburger.) 



no necessary relation between number of styles and stigmas 

 and the number of seeds which may be produced. 



It is interesting to note that many monocotyledon ( 141) 

 flowers have their parts in threes, and many dicotyledons 

 have their parts in fives or fours. References to such con- 

 stant numbers in certain families of plants will be found in 

 books for identification. 



198. Position of Ovary in Flowers. In very many flowers 

 the sepals, petals, and stamens appear attached beneath 

 the ovary (Fig. 63, A ) . In some cases (e.g. , apple, squash) , the 

 ovary appears to be entirely beneath the flower; that is, 

 the sepals, petals, and stamens appear attached above the 

 ovary (Fig. 63, C). There are still other flowers which are in- 

 termediate, as shown in B and B' of the same figure. Special 

 names are often applied to these conditions when describing 

 species. 



