Most Pears depend on birds for the dispersion of their seeds, but one striking variety prefers to attract bees, and the larger insects for cross-fertilization, and it has therefore assumed brilliant crimson petals of a broadly expanded sort, instead of bearing a succulent edible fruit, This is the highly ornamental _Pyrus Japonica_, which may so often be seen trained on the sunny walls of cottages. PELLITORY. A plant belonging to the order of Nettles, the Pellitory of the Wall, or Paritory--_Parietaria_, from the Latin _parietes_, walls--is a favourite Herbal Simple in many [424] rural districts. It grows commonly on dry walls, and is in flower all the summer. The leaves are narrow, hairy, and reddish; the stems are brittle, and the small blossoms hairy, in clusters. Their filaments are so elastic that if touched before the flower has expanded, they suddenly spring from their in curved position, and scatter the pollen broadcast. An infusion of the plant is a popular medicine to stimulate the kidneys, and promote a large flow of watery urine. The juice of the herb acts in the same way when made into a thin syrup with sugar, and given in doses of two tablespoonfuls three times in the day. Dropsical effusions caused by an obstructed liver, or by a weak dilated heart, may be thus carried off with marked relief. The decoction of _Parietaria_, says Gerard, "helpeth such as are troubled with an old cough." All parts of the plant contain nitre abundantly. The leaves may be usefully applied as poultices. But another Pellitory, which is more widely used because of its pungent efficacy in relieving toothache, and in provoking a free flow of saliva, is a distinct plant, the _Pyrethrum_, or Spanish Chamomile of the shops, and not a native of Great Britain, though sometimes cultivated in our gardens. The title "Purethron" is from _pur_, fire, because of its burning ardent taste. Its root is scentless, but when chewed causes a pricking sensation (with heat, and some numbness) in the mouth and tongue. Then an abundant flow of saliva, and of mucus within the cheeks quickly ensues. These effects are due to "pyrethrin" contained in the plant, which is an acid fixed resin; also there are present a second resin, and a yellow, acrid oil, whilst the root contains inulin, tannin, and other substances. When sliced and applied to the skin it induces heat, [425] tingling, and redness. A patient seeking relief from rheumatic or neuralgic affections of the head and face, or for palsy of the tongue, should chew the root of this _Pyrethrum_ for several minutes. The "Pelleter of Spain" (_Pyrethrum Anacyclus_), was so styled, not because of being brought from Spain; but because it is grown there.