212 



ORCHIDACEyE. 



[CLASS 



FIG. 176. Column of Lady's Slipper. 



An American genus, Vanilla, affords a fragrant fruit, 

 imported as Vanilla, and used in flavouring confectionery. 



69. Natural Order Irideas. The Iris Family. 



DISTRIBUTION. Occurring in both hemispheres ; most 

 numerous in the temperate zones, and more especially at 

 the Cape. British genera 4, species 6. 



Herbs. Perianth-leaves 6. Stamens 3. Ovary inferior. 



Type Yellow Flag (Iris pseudacorus). 



A perennial herb with a thick shortly-creeping rhizome, 

 distichous sword-shaped leaves, and showy yellow herma- 

 phrodite flowers. 



OBSERVE the equitant bases of the leaves, which are 

 folded up the mid-rib and vertically flattened throughout, 

 having the two sides of their upper surface coherent in 

 the upper part of the leaf, so that each exposed surface 



