INSECTIVOROUS AND CLIMBING PLANTS. 337 



when in its course it nears the parent stem the tendril 

 moves slowly, as if to gather strength, then stiffens 

 and rises into an erect position parallel with it, and so 

 passes by the dangerous point ; after which it comes 

 rapidly down to the horizontal position, in which it 

 moves until it again approaches and again avoids the 

 impending obstacle. 



Climbing plants are distributed throughout almost 

 all the natural orders. In some orders climbing is 

 the rule, in most it is the exception, occurring only in 

 certain genera. The tendency of stems to move in 

 circuits — upon which climbing more commonly de- 

 pends, and out of which it is conceived to have been 

 educed — is manifested incipiently by many a plant 

 which does not climb. Of those that do there are 

 all degrees, from the feeblest to the most efficient, 

 from those which have no special adaptation to those 

 which have exquisitely-endowed special organs for 

 climbing. The conclusion reached is, that the power 

 "is inherent, though undeveloped, in almost every 

 plant ; " " that climbing plants have utilized and per- 

 fected a widely-distributed and incipient capacity, 

 which, as far as we can see, is of no service to ordi- 

 nary plants." 



Inherent powers and incipient manifestations, use- 

 less to their possessors but useful to their successors — 

 this, doubtless, is according to the order of Nature ; 

 but it seems to need something more than natural se- 

 lection to account for it. 



