Prtckly Leaves. 3 1 



from attack by prickly appendages need scarcely be 

 mentioned. In the district of Monte Baldo, as also in 

 the mountainous regions lying to the east and stretch- 

 ing out beyond the Etsch, a species of Testuca {Festuca 

 alpestris Eom. et Schult.), is to be found very fre- 

 quently growing in thick patches. This grass has 

 sttEf leaves which end in needle-shaped points, and 

 when it grows in any abundance is burnt by the 

 shepherds, because the grazing animals, in search- 

 ing for other plants that grow with it, often get 

 their nostrils pricked, and come home bleeding from 

 their pasture-grounds. When it is the fully-developed 

 leaves that require this kind of protection from 

 grazing animals, one finds the thorns and prickles 

 developed on the outer surface of the bushes and 

 shrubs. When, on the other hand, it is the buds, the 

 young unfolding leaves, or the bark, which must be 

 insured against attack, or when the purpose is to 

 keep off animals that creep up from the ground, it is 

 on the stems that prickles are found, or it is the leaves 

 or the stipules which are transformed into such organs. 

 Many trees that are provided with thorns while young 

 cease to develop such appendages when once they 

 have attained a certain height. Tor their upper 

 boughs, being above the reach of browsing animals, 

 require no further protection for their leaves. 



In many cases, it is true, it is only a portion of the 

 foliage that is protected in the above-mentioned ways 



