REPRODUCTION 



195 



cult or impossible and cross-pollination made easy. This is 

 sometimes accomplished hy floral dimorphism (Fig. 108), in which 

 there are two types of flowers, so constructed that the points 



Fig. 108. — Dimorphic flowers of Chinese primrose {Primula sinensis). A, 

 flower with long style and with stamens attached low in the tube of the corolla. 

 B, flower with short style and with stamens in the throat of the corolla. 



Fig. 109. — Flowers of the mountain laurel (Kalmia lalifolia). The anthers 

 are held in little pockets in the corolla, but the disturbance of the flower, as by 

 the alighting of an insect upon it, will release the stamens and they will snap 

 upward sharply, thus covering the insect with pollen. 



where the anther and stigma touch the insect's body are exactly 

 reversed, with the result that the pollen of one is apt to reach 

 the stigma of the other. More common are the various and often 

 intricate devices in which hairs, springs (Fig. 109), traps, and 

 other agencies are employed. These reach their highest develop- 



