A married couple, friends of my own, went to live, about fourteen years ago, in a newly built, detached house, standing in its own garden, in the neighbourhood of an English city. After they had been there two years the lady developed a very painful eruption or eczema on the face, which, in the course of a few weeks, caused the eyes, nose, and lips to swell to an extraordinary degree, accompanied by the formation of blisters and breaking of the skin. The affection spread to the body, and caused constant pain and corresponding prostration. Her medical attendants were unable either to cure or to account for her condition. After some months she left home, and entirely recovered. But every year the same distressing and disfiguring illness attacked her (commencing in the month of June), and disappeared as soon as she left her house, only to return when she came back to it. The doctors spoke of her affliction as a mysterious form of erysipelas, and even suggested blood-poisoning as the cause. For long periods she was so ill and in so much pain that she was unable to see her friends, and her life was at times in danger. Two years ago a weekly newspaper published an account, written by a correspondent, of an illness from which he had suffered—exactly agreeing with that which had for so many years tortured my friend’s wife. This writer stated that he had ascertained that the disease was due to the action of a poison given off by a creeper which grew on the walls of his house. He had supposed this plant to be a Virginian creeper; but he had discovered that it was in reality the Californian poison-vine called by botanists _Rhus toxicodendron_. The terribly poisonous nature of this plant is well-known to the people of the United States. It is one of the sumach trees, of which other poisonous kinds are known, whilst more than one species is used (especially in Japan) for preparing a resinous varnish which is used in the manufacture of “lacquered” articles. The writer in the weekly paper stated that he had cut down and burnt the poison-vine which grew on the walls of his house, and that his sufferings had ceased. My friend happened to read this account, and immediately examined his own house. He found a creeper resembling a Virginian creeper, but having three leaflets or divisions of the leaf instead of five, growing around his drawing-room window, and actually spreading its branches and leaves over the window of his wife’s bedroom. He sent specimens of the creeper to Kew, where it was at once identified as the _Rhus toxicodendron_ or American poison-vine or poison-ivy. He caused the plant to be removed and burnt, and, except for a slight attack in July, due no doubt to fragments of the leaves still carried about in the form of dust, his wife has recovered her health.