Euphorbia Canariensis

This plant grows in abundance in the

Canary Islands and Teneriffe, in dry, rocky districts, where

little else can grow, and where it attains a height of 10 feet,

with the branches spreading 15 or 20 feet. It is one of the kinds

that furnish the drug known as _Euphorbium_. The milky juice

exudes from incisions made in the branches, and is so acrid that

it excoriates the hand when applied to it. As it hardens it falls

down in small lumps, and those who collect it are obliged to tie

cloths over their mouths and nostrils to exclude the small, dusty

particles, as they produce incessant sneezing. As a medicine its

action is violent, and it is now rarely employed. There are a vast

number of species of _Euphorbia_, varying exceedingly in their

general appearance, but all of them having a milky juice which

contains active properties. Many of them can scarcely be

distinguished from cactuses so far as relates to external

appearances, but the milky exudation following a puncture

determines their true character. _E. grandidens_ is a

tall-growing, branching species, and attains a height of 30 feet.

The natives of India use the juice of _E. antiquorum_, when

diluted, as a purgative. The juice of _E. heptagona_ and other

African species is employed to poison arrows; the juice of _E.

cotinifolia_ is used for the same purpose in Brazil. The roots of

_E. gerardiana_ and _E. pithyusa_ are emetic, while _E.

thymifolia_ and _E. hypericifolia_ possess astringent and aromatic

properties. The poisonous principle which pervades these plants is

more or less dissipated by heat. The juice of _E. cattimandoo_

furnishes caoutchouc of a very good quality, which, however,

becomes brittle, although soaking in hot water renders it again

pliable. _E. phosphorea_ derives the name from the fact of its sap

emitting a phosphorescent light, on warm nights, in the Brazilian

forests.