292 The Romance of Wild Flowers 
easily detached from their stalks, and go flying upon 
the breeze to various distances, until they catch in 
the hedge or the wind drops momentarily. Thus the 
old tree gets its children distributed at sufficient 
distance to give them a chance of growing upon a 
spot unoccupied by other trees. 
The Stinging Nettles (Urtica) have developed the 
art of self-defence to a very high degree of perfection. 
Though the stems are weak 
_—_ and juicy, and the leaves thin, 
aes they are both protected at every 
a point by a close armature of 
stings constructed on the prin- 
ciple of the adder’s venomous 
tooth. The stings are in this case hollow hairs 
with very fine firm points, capable of piercing 
most skins, and at their base is an _ elongated 
bulb-like poison-sac. When the point enters the 
human hand, it gets broken off where the hair is 
hollow, and the pressure of contact causes the acid 
poison to be forced up from the bag, through the 
hollow hair and into the wound, to set up that 
burning irritation which is so annoying to the 
incautious meddler with Nettles. Ourcommon Great 
Nettle (U. dioica) is still esteemed by many as a 
table-vegetable, and no doubt other creatures besides 
man would eagerly browse upon it but for these 
virulent stinging hairs. One has but to try the effect. 
of these upon his wrist to understand how animals 
with tender lips would leave them alone, even when 
hungry, and to appreciate the cuteness of such plants 
as Nettle-leaved Bellflower and the Dead Nettle in so 
growing as to present a very passable likeness to these 
Nettle sting 
