The root of our Arum also deserves a particular examination. It is a white tubercular stock or stem, containing a quantity of fecula, mixed, as in the West Indian manioc, with an acrid poisonous principle which produces a burning painful heat in the throat. This injurious principle is destroyed by exposure to the fire, and by repeatedly boiling the plant in water. After being thus heated, there remains only the fecula, in the form of a white powder, which, in times of scarcity, supplies a very nutritious food. "I made use of it," says Bosc, "during the storms of the Revolution, when I had taken refuge in the solitudes of the forest of Montmorency. This plant is so abundant in this forest, and in many other localities, that, at the epoch I speak of, it would have ensured the subsistence of several thousands of men, if they had known its alimentary properties. I was seriously counting on the resources which it would place at my disposal, when the death of Robespierre relieved me from my difficulties."[54] Our _arum_, which we have taken as a type of the family of the Aroidaceæ, is called _maculatum_, or "spotted," in allusion to the white and violet spots with which its leaves are besprinkled. [Illustration: FIG. 34.--The _Arum arisarum_.] Another, and not less interesting species, is the _Arum arisarum_. (See Fig. 34, _a_.) It loves to display its exquisite leafage on the rocks bordering the "sea-marge," and is found in profusion along almost the entire littoral of the Mediterranean. It is a precocious flower--making its appearance about the end of December, and flourishing until the beginning of Spring. The spathe, which in the _Arum maculatum_ has all the aspect of an etiolated leaf, assumes, in the _Arum arisarum_, the tints of a corolla,--is of a beautiful warm red violet, streaked with white. The fleshy axis, which ought rather to be called gynandrous (both male and female) than a spadix, is of a red colour; naked in its upper portion, which terminates with a kind of apple. It would remind a drummer-boy of the formidable staff carried by his drum-major (see Fig. 34, _b_.); the stamens, reduced to the condition of bilobed anthers, are mounted around the central part; and the ovaries, less numerous than the stamens, occupy the base of the axis. Each monocular ovary is crowned by a sessile stigma, and each lobe contains a great number of erect ovules. In the _Arum maculatum_, the number of ovules does not exceed six. Some botanists have laid hold of this characteristic as an excuse for withdrawing the Mediterranean species from the _arums_, and creating a new genus, _arisarum_. The variety we have just described is, in that case, denominated the _Arisarum vulgare_. * * * * *