MENTALITY AND SPIRITUALITY 189 
every vibration—for sound is but the effect of vi- 
brations. 
The examples of a plant’s sense of touch and of 
feeling are numerous. The action of the tentacles 
of the sundew, on being touched by a foreign sub- 
stance, is evidence of this ability to feel. Plant 
consciousness of heat and cold frequently has been 
proved by approaching a flower with a hot iron; 
there may be no change in the light, but with the 
change of temperature, the flower closes, as if to 
protect its precious children from harm. 
That plants have a sense of smell also has been 
proved. An odour which is offensive to a plant will 
cause it to close; and if endured long it may kill 
the plant. The wonderful power of plants to de- 
tect approaching rain, or the nearness of water, 
may fairly be attributed to the sense of smell; al- 
though this power might quite as fairly be attrib- 
uted to a sixth sense of the plant. 
The taste of plants has been proved beyond ques- 
tion; it is known that the taste of some plants for 
salt, others for sugar, iron, zinc, is very marked. 
There can be little question that the prevalence or 
scarcity of a favourite food has much to do with 
a plant’s habitat. 
The sixth sense which plants undoubtedly pos- 
sess may be called the psychic sense. There are 
