In certain deserts along the Volga River in Russia, a peculiar fern may be found. It might be described as resembling a gigantic Polypody; the stem is about as thick as a lamb's body and grows horizontally on the ground like that of the common fern mentioned; thick furry scales cover the outside of its stem, which ends at the tip in an elongated point. The blackish-green leaf-stalks springing from the furry stem end in large divided green leaves. It occurred to some medieval humorist to cut off the upper part of the leaf-stalks, and to make a sort of toy lamb out of the four leaf-stalk stumps and part of the woolly or furry stem. This was palmed off as a wonderful curiosity of nature, as "a plant that became an animal," upon the ingenuous tourist of the period. Such a subject was thoroughly congenial to the learned mind in the Middle Ages, and an enormous quantity of literature was produced in consequence. The general theory is given in the following lines:-- "Cradled in snow and fanned by Arctic air, Shines, gentle Barometz, thy golden hair, Rooted in earth each cloven hoof descends, And round and round her flexile neck she bends, Crops the grey coralmoss and hoary thyme, Or laps with rosy tongue the melting rime, Eyes with mute tenderness her distant dam, Or seems to bleat, a vegetable lamb." Such is the old idea of a well-known fern, _Cibotium barometz_. Yet the original researches of some African "Obi" wizard or red Indian were not forgotten, and gradually came into practice. [Illustration: THE GARDEN OF EDEN The title-page of John Parkinson's "Paradisus." In the distance may be seen a Scythian Lamb growing on its tree, and in the foreground many plants are shown as well as Adam and Eve.] It must be remembered that these savages were true scientific experimentalists, and made discoveries which have been of infinite service to mankind. We remember great men like Harvey, Lister, and Pasteur, but we never think of the Indian who discovered quinine. The quinine trees, the yellow variety or _Calisaya cinchona_, grow in the mountains of north-eastern Bolivia and south-eastern Peru, in wild, inaccessible places at heights of 5000 to 6000 feet. The Indians probably experimented with almost every part of every wild tree before they discovered the wonderful properties of this particular species. The quinine in nature is probably intended to prevent some fungus or small insect from attacking the bark: when quinine is used in malaria, it kills the fever germ which attacks the blood corpuscles of the sick person, so that it is of the utmost importance in all tropical countries.