172 



ELEMENTS OP BOTANY. 



bee which may enter. A little study of Pig. 156 will make 

 clear the way in which the anthers are hinged, so that a bee 

 striking the empty or barren anther-lobes a knocks the poUen- 



FiG. 156.— 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, a', anther-cells. C, the anthers and 

 connectives hent into a horizontal position hy an insect pushing against a. 



bearing lobes a! into a horizontal position, so that they will 

 lie closely pressed against either side of its abdomen. 



I n m IV 



Fig. 157.— Dimorphous Flowers of the Primrose. 



I, II, short-styled form ; III, IV, long-styled form, natural size ; a, throat of 



the corolla ; 5, s, stamens ; G, gr, styles. 



210. Flowers with Stamens and Pistils each of Two Lengths. 

 — The flowers of bluets, partridge-berry, the primroses and 

 a few other common plants secure cross-fertilization by hav- 



