150 MYSTERIES OF THE FLOWERS 



But in the Gyrostachys the pollen is held be- 

 tween the forked, or two-toothed, beak which ter- 

 minates the column, in a kind of sugar-tongs con- 

 trivance which comes away with its contents of pol- 

 len-masses upon the slightest touch of the insect. 



The first sketch shows a young flower with the 

 beak in place on the column. The 

 second shows the beak or tongs split 

 open and discharging the pollen. 

 The third shows an older flower, 

 whence pollen has been removed 

 and where the column has risen, 

 exposing its stigmatic surface to 

 the approach of the visitor, often a 

 bumblebee. 



The reader will understand with 

 what precision the mechanism TRESSES 

 works, sending away its own charge of pollen, 

 then readjusting itself to receive some pollen from 

 another flower. 



Certain orchids, as we have said, enclose their 

 pollen in little boxes which open only as the insect 

 backs out of the flower, and snap shut again. The 

 contrivance reminds us somewhat of the mechanism 

 on the stigma of the iris, a lip which acts as a lid 

 to protect it from the touch of its own pollen, or as 

 a scoop to scrape up pollen brought from a distant 

 source. But the places of stamens and stigma are 



