HOME PLANTS AND THEIR WAYS. 13 



5. Questions are often asked in gardening periodicals as 

 to how hops or other climbing plants always manage to 

 grow precisely in the direction in which they will find a 

 support. This fact has surprised many observers, who 

 have supposed that climbing plants have some occult sense 

 by which they discover the whereabouts of the stick up 

 which they subsequently climb. But there is in reality no 

 kind of mystery in the matter : the growing shoot simply 

 goes swinging round till it meets with a stick, and then it 

 climbs up it. Now, a revolving shoot may be more than 

 two feet long, so that it might be detained in its swmging- 

 round movements by a stick fixed into the ground at a dis- 

 tance of nearly two feet. There would then be a straight 

 bit of stem leading from the roots of the plant in a straight 

 line to the stick up which it twines, so that an observer 

 who knew nothing of the swinging-round movement might 

 be pardoned for supposing that the plant had in some way 

 perceived the stick and grown straight at it. This same 

 power of swinging round slowly comes into play in the very 

 act of climbing up a stick. 



6. Suppose I take a rope and swing it round my head : 

 that may be taken to represent the revolving of the young 

 hop-shoot. If, now, I allow it to strike against a rod, the 

 end of the rope which projects beyond the rod curls freely 

 round it m a spiral. And this may be taken as a rough 

 representation of what a climbing plant does when it meets 

 a stick placed in its way. That is to say, the part of the 

 shoot which projects beyond the stick continues to curl in- 

 ward till it comes against the stick ; and, as growth goes 

 on, the piece of stem which is projecting is, of course, all 

 the while getting longer and longer ; and, as it is continu- 

 ally trying to keep up the swinging-round movement, it 

 manages to curl round the stick. But there is a difference 

 between the rope and the plant in this — that the rope curls 

 round the stick at the same level as that at which it is 



