38 Bulletin of the Natural History Society. 
NOTE ON LINARIA CYMBALARIA. 
BY JAMES VROOM. 
It may not be generally known that the rare phenomenon of 
apheliotropism, or turning from the light, is observable in the 
peduncles of the common Kenilworth or Coliseum Ivy (Linaria 
Cymbalaria.) This little plant raises its flower buds an inch or 
more above the trailing stem ; but, as soon as the flower opens, the 
base of the flower stalk begins to bend downward, the middle of the 
stalk at the same time bending in the opposite direction, so that ihe 
lower part of the peduncle takes the form of the letter S laid on its 
side {m ) — the portion immediately below the flower still being 
erect. The second curvature, however, does not remain, but passes 
slowly along the flower stalk, drawing the flower downward, so that 
soon after the corolla falls the growing seed pod lies upon the 
ground, or, where the stem is raised high enough to admit of it, 
points directly downward. This might seem to be due to the 
influence of gravitation, but when the plant is grown before a 
window (as we frequently see it here) the fruit stalks, instead of 
reaching downward, are found extending towards the darkest part 
of the room. 
In a room with one window, a pot of Linaria was hanging near 
the blind, so that the light could not reach it from above. The 
peduncles, which lengthen considerably after flowering, stretched out 
two or three inches horizontally, and where they received the 
strongest light from below even took an upward direction. The pot 
was turned around so that the stalks were parallel with the glass. 
In three hours the growing peduncles could be seen turning away 
from the light, and in a day or two most of them were found bent 
at right angles, the curvature in this case seeming to begin 
immediately below the seedpod. Yet a certain amount of light is 
necessary for perfecting the seed ; for when moved to a darker place 
the peduncles, though still pointing towards the darkest part of the 
room, were “ drawn ” to twice their usual length and presented the 
general appearance of a plant sufiering from want of sufiicient light. 
