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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



utilized by the slowly revolving coil until the tip was free to move 

 forward and complete the grasp it had attempted. One hour had elapsed 

 since it began." 



Mr. Shannon follows the above account by showing how the subsequent 

 coils are made in the attached tendril, half the number of coils being in 

 one direction, and half in the opposite — a mathematical necessity to 

 balance opposing strains. 



" Having caught and coiled firmly round an object, the tendril makes 

 a sort of loop near the point of attachment of the tip. Then a broad 

 bent portion swings slowly and gradually downwards. This portion, 

 which may be likened to the crank-handle on the middle of a shaft, 

 continues to swing downwards, and then backwards and upwards, com- 

 pleting one revolution. As it does this the tendril becomes coiled on 

 both sides of the 'crank,' in one direction on one side and in the opposite 

 direction on the other." 



This crank motion being repeated again and again, the numerous 

 opposing coils are made. The use to the tendril is the elasticity afforded, 

 allowing for a pull or jerk without rupturing it. Moreover, as soon as 

 the strain is felt, the whole length of the tendril thickens and becomes 

 consolidated. 



[Figures 78 to 81 and 84 to 87 are from " Buds and Stipules," by 

 kind permission of the author, Lord Avebury, and figures 82 and 83 from 

 Darwin's "Movements and Habits of Climbing Plants," by kind per- 

 mission of Mr. John Murray.] 



