172 



ELEMENTS OP BOTANY. 



bee which may enter. A little study of 3?'ig. 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 pollen- 



Fro. 156. — Flower and Stamens of Common Sage. 



A,p, stigma ; ft, anthers. B, the two stamens in ordinary position ; f, filaments ; 

 7n, connective (joining anther -cells) ; a. a', anther-cells. C, the anthers and 

 connectives bent into a horizontal position by 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. 



Fro. 157. — Dimorphous Flowers of the Primrose. 



I, II, short-styled form ; III, IV, long-styled form, natur.il size ; a, throat of 



the corolla ; S, s, stamens ; G, ^7, styles. 



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

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

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



