Il6 THE STORY OF THE PLANTS. 



in the shade, the crocuses are open in the sun- 

 shine to welcome them. 



But other irises are more complicated, like the 

 gladiolus, and still more the garden irises, in 

 which the difference between the calyx and corolla 

 is carried to its furthest point in this family. The 

 sepals in true irises are large and brilliantly col- 

 oured; they hang over gracefully; the petals are 

 smaller and erect ; the stigmas are so expanded 

 as to look like petals ; and they arch over the 

 stamens in a most peculiar manner. If you watch 

 a bee visiting a garden iris, you will see for your- 

 self the use of this most peculiar arrangement; 

 the bee lights on the bending sepal, and inserts 

 his head between the stigma and the stamen in a 

 way which renders fertilisation simply inevitable. 

 But the most curious part of it all is that the 

 flower, from the point of view of the bee, resem- 

 bles three distinct and separate blossoms ; he 

 alights one after another on -each bending sepal, 

 and proceeds to search for honey as if in a new 

 flower. 



Highest of all the threefold flowers, and most 

 wonderful in their marriage customs, are the 

 great group of orchids, some of which grow wild 

 in our English meadows, while others fix them- 

 selves by short anchoring roots on the branches 

 of trees in the tropical forests. Many of these 

 last produce the handsomest and most extraor- 

 dinary flowers in the world, and they are much 

 cultivated accordingly in hothouses and con- 

 servatories. It would be quite impossible for me 

 to give you any account of the infinite devices 

 invented by these plants to secure insect-fertilisa- 

 tion ; and even the structure of the flower is so 

 extremely complex that I can hardly undertake 



