366 



FOUNDATIONS OF BOTANY 



anthers have withered and the stigma is now lowered so 

 as to brush against the body of any bee which may enter. 



A little study of Fig. 259 

 will make clear the way 

 in which the anthers are 

 hinged, so that a bee strik- 



FIG. 259. Flower and Stamens of Common Sage. 



A, p, stigma ; a, anthers ; B, the two stamens in ordinary position ; /, filaments ; 

 m, connective (joining anther-cells) ; a', anther-cells ; C, the anthers and 

 connectives bent into a horizontal position by an insect pushing against a. 



ing the empty or barren anther-lobes, a, knocks the pollen- 

 bearing lobes, a', into a horizontal position, so that they 

 will lie closely pressed against either side of its abdomen. 



437. Flowers with Sta- 

 mens and Pistils Each of Two 

 Lengths. The flowers of 

 bluets, partridge-berry, the 

 primroses, and a few other 

 common plants secure cross- 

 pollination by having essen- 

 tial organs of two forms 

 (Fig. 260). Such flowers 

 are said to be dimorphous 

 (of two forms). In the 

 short-styled flowers, II, the 

 anthers are borne at the top 



FlG. 260. Dimorphous Flowers of 



the Primrose. 



1, a long-styled^flower ; II, a short- 



Q 



