As what has been said contains nothing that can enable us to determine the genus of the _struthium_ according to the rules of botany, we may be allowed to conjecture that it was one of those plants still used for the like purpose in Italy and other neighbouring countries. Fuchs thinks it must have been the _Saponaria officinalis_ (soap-wort), the roots of which indeed contain a saponaceous juice that readily changes the saliva into froth. The root was employed for that purpose by the impostor in Lucian; and the juice is used at present for cleaning wool and cloth. In the Helvetian Alps, the sheep, before they are shorn, are washed with a decoction of the plant and its roots; and with a mixture of ashes it serves for cleaning linen. The taste of it is so sharp, that it is compared by some to that of the small burnet-saxifrage. This _Saponaria officinalis_ however differs too much from the remaining properties[255] of the _struthium_. Its root is as thick only as a quill, or at most as one’s finger. The stem, which is three feet in height, throws out many branches, and cannot be called _caulis ferulaceus, tenuis_. It is not rough and prickly, and, instead of growing in poor rocky soil, it is rather fond of deep ground and the borders of corn-fields. We may therefore conjecture with more probability that the _Gypsophila Struthium_, Linn.[256], a plant still used for washing in the lower part of Italy and Spain, is the _struthium_ of the ancients. This opinion acquires some strength by its being adopted among the Italians and Spaniards; and because the plant, as Pliny says, grows in a rocky soil and on the mountains. It is also still called _lanaria_ by the Calabrian peasants. It has a tender stem; its leaves are so like those of the olive-tree that they might be compared to them by those who are not botanists; and its root is large, but it is neither rough nor prickly. This contradiction may be accounted for by supposing that Pliny, through a mistake, of which I have already accused him, ascribed falsely to the soap-plant the prickly or rough leaves of the dye-plant which had an affinity to madder. But even after this explanation there still remains to be got over a dubious passage of Theophrastus, who indeed seems to make the plant prickly also.