192 The Great World's Farm 



height, are five stamens standing up Hke teeth, the stalks 

 being so very short that they are almost all anther. In 

 spite of their shortness, however, the stamens are on a 

 level with the long pistil of the other blossom, for they are 

 attached to the flower-tube, and for the long pistil their 

 pollen is intended. The pollen-grains of the stamens 

 which grow with the long pistil — but out of sight, half- 

 way down the tube — are intended for the short pistil, 

 whose knob is just at their own level, and accordingly, 

 they are smaller. 



All flowers which vary in this way, all which are dis- 

 tinguished by color, scent, size, or irregularity of shape, 

 are mainly indebted for fertilization to insects. This is 

 the case with all bell-shaped and tubular flowers, also with 

 the snap-dragon and foxgloves, and with the dead nettles, 

 lavender, thyme, and all blossoms of similar shape to 

 these, besides many others. In some the shapes of the 

 blossom and of the insect by which it is fertilized are as 

 beautifully and "exactly fitted one to the other as the lock 

 is to the key," and in others there are endless different 

 devices for securing, that the visitor shall not depart with- 

 out doing some service in return for the pollen or nectar 

 which it has consumed or carried off. 



In the common stinging nettle the four stamens He 

 folded down flat until they are touched, when they spring 

 suddenly up and scatter their pollen; a needle inserted in 

 the throat of the common purple lucerne causes two 

 stamens instantly to start up like a jack-in-the-box, the 

 anthers at the same time exploding and discharging their 

 dust. A similar explosion takes place in the flowers of 

 the whin, and in many others. In one plant the anthers 

 act like a pair of bellows, and on being touched blow their 



