106 ROCK PLANTS OF THE PASTURES 



the hairy, inflated calyx formed by the united sepals. 

 The leaves also end in large terminal leaflets, an inch 

 or more in length. It is a biennial plant, existing 

 for two years only. 



In this species also, the flowers are very variable 

 in colour. Usually yellow, they may be almost white, 

 or again more or less red, or entirely so. They are 

 frequently cross-fertilised by butterflies in the Alps, 

 though in the plains, humble-bees are the chief and 

 most useful visitors. Like the Bird's-foot Trefoil, it 

 is one of the most important pioneers of vegetation 

 on the bare stony patches of the pastures, on the 

 moraines of glaciers, and the debris brought down by 

 streams. 



The White Dryas. 



The White Dryas {Dryas octopetala, Linn., natural 

 order Eosaceae, the Eose family) is one of the most 

 beautiful of Alpine plants, flourishing in similar 

 habitats to the preceding. Its large white or yellowish- 

 white flowers form a welcome landmark on many a 

 bare patch in the pastures. 



The habit of the White Dryas (Plate XXV.) is 

 very characteristic of that of many Alpines. It is 

 what is called a carpet plant. Other examples of 

 carpet plants will be found in the Trailing Azalea, 

 the Alpine Juniper, and Globularia cordi/olia. 



A carpet plant is really a very dwarf, recumbent 

 shrub : one might almost say a miniature tree. The 

 plant is woody and not herbaceous. The stem is very 



