JULY. 305 



heaven, and was returning thither, But when she has 

 to provide for her future progeny, does she deposit 

 her eggs on the brilliant flowers where she spent her 

 bridal ? JSTo ! she retires to the nettles, and there 

 safely leaves the infant embryo of a future race secure 

 amidst the armature of the urticce. Thus a host of 

 insects are sustained by an apparently useless weed, 

 which is itself kept within due bounds by the cater- 

 pillars that feed upon it." .* The economy of the 

 Nettle, then, merits the closest investigation. Its 

 stings, as they are called, are extremely curious, and 

 there is a striking analogy between them and the 

 fangs of poisonous serpents. In both cases the 

 wounding instrument is hollow, and conveys the poi- 

 son by a channel from the secreting gland to the 

 wound. In the serpent, indeed, the channel does not 

 run to the point of the fang, but opens at some dis- 

 tance behind it ; while in the nettle the perforation 

 extends through the very point. A microscope of 

 moderate power will show the stings to be highly 

 polished and exquisitely pointed transparent setae, 

 furnished at their base with a kind of bulb, cellular 

 and spongy within, in which the acrid poison is con- 

 tained. Thus, when the point of the sting comes in 

 contact with any object, its base is pressed down upon 

 the spongy pedestal, the venom instantaneously darts 

 up the tube, and pours its contents upon the unwary 

 assailant. This " points a moral" not unworthy of 

 notice. Touch the nettle ever so gently it stings 

 with its usual acrimony ; but grasp it stoutly, and no 



* Quoted from a Lecture on the Analogies and Harmonious Associations 

 of Plants with Animals, delivered by the Author before the Worcestershire 

 Natural History Society ; and published when he was Honorary Curator 

 to that body, in 1834. 



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