In Mexico there grows a herb, familiarly known there as the Loco or Rattle Weed, which has such a powerful effect on animals, that horses eating it are driven raving mad.
In Scotland there is a certain weed that grows in and about the Borgie Well at Cambuslang, near Glasgow, which possesses the awful property of making all who drink of its waters mad. Hence the local saying:
“A drink of the Borgie, a bite of the weed, Sets a’ the Cam’slang folk wrang in the head.”
Some few plants are repellent from the obnoxious smells which they emit: among these are the _Phallus impudicus_, and many of the Stapelias. One--the Carrion-flower--has an odour so like putrid meat, that flesh flies, attracted by it, deposit their ova in the flowers; and when the maggots are in due course produced, they perish miserably for lack of food.
Zahn, in his _Speculæ Physico-Mathematico-Historicæ_ (1696) enumerates several trees and plants which had, in his day, acquired a very sinister reputation. He tells us that--
“Herrera speaks of a tree, in Granada, called _Aquapura_, which is so poisonous, that when the Spaniards, at first ignorant of its deadly power, slept under its shade, their members were all swelled, as if they had taken dropsy. The barbarians also, who lingered naked or intoxicated under it, had their skin broken by large swellings, which distended their intestines, and brought them to a miserable death.
“There is a tree in Hispaniola, bearing Apples of a very fragrant smell, which, if they are tasted, prove hurtful and deadly. If any one abides for a time beneath its shade he loses sight and reason, and cannot be cured save by a long sleep. Similar trees are found in the island Codega.
“In the same island, Hispaniola, another kind of tree is found which produces fruit formed like Pears, very pleasant to the sight, and of delicious odour. If any one lies beneath its shade and falls asleep, his face begins to swell, and he is seized with severe pain in the head, and with the sorest cold. In the same island another tree is found, whose leaf, if touched, causes at once a tumour of a very painful nature to break out, which can only be checked and healed by frequent washing with sea water. There also grows a plant called _Cohobba_, which is said to be lymphatic. It intoxicates by its mere smell, and renders fanatical, Cardanus believes this plant to be of the _Stramonium_ (_Datura_) family, which infuriates those who drink it.