To Pliny’s discussion of herbs we may append some specimens of the employment of magic procedure in agriculture and of the superstitions of the peasantry in which his pages abound. To guard against diseases of grain the seeds before planting should be steeped in wine, the juice of a certain herb, the gall of a cow, or human urine, or should be touched with the shoulders of a mole[326]—the animal whose use by the _magi_ we heard Pliny ridicule. One should sow at the moon’s conjunction. Before the field is hoed, a frog should be carried around it and then buried in the center in an earthen vessel. But it should be disinterred before harvest lest the millet be bitter. Birds may be kept away from the grain by planting in the four corners of the field an herb whose name is unfortunately unknown to Pliny.[327] Mice are kept out by the ashes of a weasel, mildew by laurel branches, caterpillars by placing the skull of a female beast of burden upon a stick in the garden.[328] To ward off fogs and storms from orchards and vineyards a frog may be buried as directed above, or live crabs may be burnt in the trees, or a painted grape may be consecrated.[329] Suspending a frog in the granary preserves the corn stored there.[330] To keep wolves away catch one, break its legs, attach it to the ploughshare, and thus scatter its blood about the boundaries of the field; then bury the carcass at the starting-point.[331] Or consecrate at the altar of the Lar the ploughshare with which the first furrow was traced. Foxes will not touch poultry who have eaten the dried liver of a fox or who wear a bit of its skin about their necks. Fern will not spring up again if it is mowed with the edge of a reed or uprooted by a ploughshare upon which a reed has been placed.[332] Of the use of incantations in agriculture we shall treat later. [Sidenote: Virtues of stones.]