272 



FLOWERS 



inner part. In these inner parts originate those hidden 

 generations which produce the sex organs. 



a. The Stamens. — As has been noted, there are two 

 kinds of inner parts. There is usually a central structure 

 called the pistil, and it is usually surrounded by other 

 structures called the stamens. The stamens are slender 

 organs at whose upper ends are borne little sacs which 

 contain pollen. (See Figure g6.) Usually there are one or 

 two whorls of stamens. Taken all together, the stamens 

 form the andrcecium. The pollen-contain- 

 ing part at the tip of the stamen is called 

 the anther; it is usually composed of two 

 distinct lobes or pollen sacs. (See Figure 

 g6.) That part of the stamen which sup- 

 ports the anther is called the filament. 

 Usually the filament is quite slender. 



b. The Pistil. — The pistil is the most 

 complicated of all the parts of the flower. 

 It is the part within which the seed is pro- 

 duced. It is the part which develops into 

 the fruit. It is the part into whose tissues 

 the pollen tube penetrates, carrying with 

 it one of the hidden generations. It is 

 the part within whose tissues develops that other hidden 

 generation which is also concerned with the sex process. 

 It is the part within which one of the cells of the pollen 

 tube unites with one of the cells of the other hidden genera- 

 tion. 



From top to bottom pistils are usually divided into three 

 distinct regions. (See Figure gy.) At the top there is an 

 expanded sticky part which catches and holds the pollen 

 brought by insects or otherwise. This part is called the 



Fig. 96. — Stamens, 

 showing filament, 

 anther, and the 

 two pollen sacs of 

 which the anther 

 is composed. 



