JULY 163 



title of Ampelopsis japoriica, although Ampelopsis 

 being a true vine, belongs to a very different natural 

 order to Rhus. The confusion is increased by the 

 splendour of the poison ivy in autumn, when the 

 foliage fades through brilliant tints of yellow and 

 scarlet. Having enjoyed its beauty for many years in 

 my own garden, where it luxuriates, I begin to think 

 that it is time to turn it out. Considering the wealth of 

 hardy exotics one has to choose from, the presence of 

 poison ivy might well be dispensed with, except in 

 botanical gardens. 



The mischievous agent in this plant is toxic that 

 is, it consists of an active poisonous principle, affecting 

 the nerves and circulation; in fact, it has long been 

 recognised as a powerful drug in the homoeopathic 

 pharmacopoeia; but it has never been explained to 

 the writer by what means the living plant can take 

 effect by mere proximity upon persons susceptible to 

 its influence. The leaves have no perceptible aroma 

 until crushed, and the inconspicuous greenish flowers, 

 produced in June, do not appear to be part of the 

 mechanism of offence. In the too common nettle 

 the mechanical and toxic agents are very neatly co- 

 ordinate. Each stinging hair is seated upon a gland 

 containing a powerful acid. The slightest pressure 

 serves to break off the blunt head of the hair, when the 

 flinty edge of the fracture penetrates the skin ; 

 simultaneously the base of the hair squeezes the 

 reservoir, causing the poison to flow into the wound, 

 the exasperating result being what we all know. But 

 no such causation can be traced in the poison ivy, 



