THE PLANT AND ITS ENEMIES 89 



In many large bushes, it is possible to trace the 

 process by which the prickles have been gradually 

 discarded ; and from a single shrub an interesting 

 series of leaves may be gathered, commencing with 

 the specimens from the lower branches, which are 

 fully armed, and ending with those from the 

 uppermost shoots, which are quite destitute of 

 any prickles. As in the case of the thorny plants, 

 it is to be noticed that prickles are produced in 

 the greatest abundance when the specimen is 

 having a hard time of it. Thus Brier Roses 

 which have been cut back in hedges send up 

 their fresh shoots abundantly supplied with 

 prickles. 



Closely allied to the prickles are the various 

 hairy appendages which are so often distributed 

 over the foliage of plants. The leaves of the 

 Orange Hawkweed, and even the flower stems, are 

 covered with stiff black hairs. Plants protected 

 in this manner are not subject to the attacks of 

 insect larvae, slugs or snails, as would probably be 

 the case if the foliage were perfectly plain. Similarly, 

 grazing animals are less inclined to regale them- 

 selves on leaves which are thickly covered with 

 bristles. 



There must be few people who have not 

 suffered at one time or another through coming 



