156 FREAKS OF PLANT LIFE. 



power appeared to be confined to the tip of the 

 radicle for about one-twentieth of an inch. When 

 the part was irritated by contact or slicing, its 

 influence extended upwards for one-third or half an 

 inch, causing the radicle to bend away from the 

 point of irritation in a symmetrical curvature. This 

 occurred sometimes within six or eight hours, and 

 almost always within twenty- four hours of the com- 

 mencement of the irritation. The curvature often 

 amounted to a right angle, occasionally the tip bent 

 upwards like a hook with its point to the zenith, or it 

 curved and formed a loop or a spire. 



The method by which these observations were 

 made was by soaking the beans in water, for about 

 twenty-four hours, then suspending them so that 

 in germinating the radicle might grow downwards 

 freel)', and without obstruction. When the radicles 

 were sufficiently protruded, small objects, such as 

 fragments of card or paper, were attached by gum- 

 water, or other cement, on one side of the tip of the 

 radicle, these were then watched for deflection. In 

 other instances slices were cut with a razor from one 

 side of the tip, so as to cause continued irritation. 

 In all these instances the radicles responded, and 

 turned away in the opposite direction to the source 

 of irritation. In cases where the tips were only 

 temporarily irritated, by striking or pricking, no 

 deflection occurred. Other tips were touched lightly 



