AUGUST 91 



cannot explain, nearly all the flowers are males, and the 

 few female flowers produce fruit which does not come 

 to perfection. On another pole I have trained Cohcea 

 scandens, a very old favourite. As a rapid-grooving 

 climber it has few equals, and its flowers, which are 

 like large bells, green at first and then turning to a 

 rich purple, are very ornamental, and when it reaches 

 the latter stage the stamens, which before were well 

 inside the flower, grow to a considerable length, pro- 

 truding far beyond the flower, and twisting themselves 

 in a curious way, for which it is very hard to give a 

 reason. But it is as a climber that the coboea is such 

 an interesting plant. Darwin, in 1865, in his delight- 

 ful paper ' On the Movements and Habits of Climbing 

 Plants,' which afterwards took a new shape in his 

 larger book on The Movements of Plants in 1880, gave a 

 long description of the movements of coboea.^ He 

 studied it as 'an admirably constructed climber,' and 

 there is probably no plant from which the method by 

 which plants climb by their tendrils can be better 

 learned. Each shoot ends in a very fine branched ten- 

 dril which stands upright, and each branchlet ends in 

 one or more very delicate claws. The tendril steadily 

 revolves in a circle till it meets with something to 

 which it can attach itself by the little claws. These 

 1 See p. 200. 



