412 CLIMBING PLANTS. 
I am led to suspect that this habit in the tendril of inserting 
its tip into dark holes and crevices has been inherited by the 
plant after having lost the power of forming adhesive disks." 
A plant of Bignonia capreolata was several times shifted 
in position in a box where one side only was exposed to the 
light; in two days all six tendrils pointed with unerring 
truth to the darkest corner of the box, though to do this 
each had to bend in a different manner. Six tattered flags 
could not have pointed more truly from the wind than did 
these branched tendrils from the stream of light which en- 
tered the box. When a tendril does not succeed in clasping 
a support it bends downwards and then towards its own 
stem, which it seizes, together with the supporting stick, if 
there be one. If the tendril seizes nothing it does not con- 
tract, spirally, but soon withers away and drops off. A 
unch of wool was placed in the way of the tendrils; they 
caught one or two fibres and then the tips began to swell 
into irregular balls above the one-twentieth of an inch in 
diameter. The surfaces of these balls secrete some viscid 
resinous matter, to which the fibres of the wool adhere, so 
that after a time fifty or sixty fibres are all deeply imbedded 
in one ball of tendril. These tendrils quite fail to attach 
themselves to a brick wall. These plants are especially 
adapted to climb trees clothed with lichens and mosses which 
abound on the trees in the native country of the Bignonia. 
Cobea scandens (Polemoniacee) is an admirable climber. 
The terminal portion of the petiole which forms the tendril 
is sometimes eleven inches long. The tendril performs one 
revolution against the sun in an hour and a quarter. The 
base of the petiole and the internodes do not move at all. 
A large majority of the tendrils of Corydalis claviculata 
still bear leaflets, though excessively reduced in size. We 
here behold a plant in an actual state of transition from a 
leaf-climber to a tendril-bearer. Whilst the plant is young, 
only the outer leaves, but when full-grown all the leaves, 
have their extremities more or less perfectly converted into 
tendri 
