30 Flowers and their Unbidden Guests. 



Draba, Plantago major, Juncus iufonius, etc.), which 

 grow along the paths traversed by grazing animals, are 

 able to maintain themselves and to develop their 

 flowers and fruit without hindrance, in spite of their 

 being exposed to the onslaught of these ruminants, has 

 again no other explanation than the presence of certaia 

 chemical compounds in the cellular juice of their 

 leaves which render them disagreeable to these animals. 



In many plants, again, the foliage is of thick and 

 leathery consistence, and this also acts as a security 

 against injury from ruminants. The wide tracts in the 

 Alps which are seen covered with evergreen carpets and 

 shrubby thickets of Azalea procwmlmis, Arctostaphylos 

 uva ursi, Bryas octopetala, Olobularia cordifolia, Glohu- 

 laria nudicauUs, Daphne striata, Em/petrwm, Vaccinium 

 vitis idaea, Mhododendron, and other characteristic 

 plants, are avoided by sheep, as also by chamois. It is 

 exceptional to find the leaves of these plants even 

 mangled by grazing animals, and we never find them 

 completely destroyed. 



Even grasses and sedges, when their leaves are un- 

 pleasantly rigid, are carefully avoided by ruminants. 

 Carex firma Host,, which grows in thick masses on the 

 wide flanks of the Alps, is never browsed. Nardm 

 stricta L. again, and Juncus trifidMS, which here and 

 ;there in the Alpine regions form the fundamental part 

 of the limited flora, are touched but exceptionally. 



That the leaves of many plants are also protected 



