Page:The American Cyclopædia (1879) Volume XIII.djvu/563

 PITCHER PLANTS 54Y and other species. Burgundy pitch is used for i plasters, and when applied for some time to the skin acts as a rubefacient, exciting slight inflammation and serous effusion, and relieving chronic affections of the chest and rheumatic pains. It is prepared from the resinous mat- ter that exudes from the Norway spruce {abies excelsa). The resin is melted in hot water, and strained through coarse cloths. Burgundy pitch is produced in Finland, the Black Forest, Austria, and Switzerland. The pure article is rather opaque, yellowish brown, hard and brit- tle when cold, yet gradually takes the form of the vessel in which it is kept. It has an aro- matic and very agreeable odor, which is quite marked when heated; it is strongly adhesive, and breaks with a clear conchoidal fracture. Few drugs are more subject to adulteration than Burgundy pitch. The true article is sel- dom met with in this country, the substance usually sold here under that name being made up of various mixtures of common rosin, wax, and fatty matters. Canada pitch resembles the preceding in its properties, and is prepared from the inspissated juice of the hemlock spruce I (abies Canadensis). The juice exudes sponta- ! neously from old hemlock trees, and hardens ! upon the bark, which is stripped off, broken i in pieces, and boiled in water. The pitch as it | rises to the surface is skimmed off, and is puri- i fied by a second boiling. It consists of resin with a little volatile oil. It melts at 198 F., and is almost too soft at the temperature of the body to be worn as a plaster. The finer quality of Canada pitch, such as hardens in clean tears in the older trees, commands a high price, being sold under the name of u spruce gum," and is used as chewing gum. The poor grades are often sold as "hemlock gum." The residue from the distillation of coal tar is also called pitch, and is used as a coloring ingredient of a coarse black varnish much used for protecting iron work from rust. An increase of tempera- ture produces decomposition, with the forma- tion of a product having the consistency of butter. Asphalt is sometimes called mineral pitch, or Jew's pitch. (See ASPHALTTJM.) PITCHER PLANTS, a general name for plants with leaves wholly or partially transformed into receptacles for water. This occurs in plants widely separated botanically, and though the grouping of them together is not a scien- tific classification, it serves to present at one view several which have no other value than the interest which is attached to this pecu- liarity of structure. (See LEAF.) The water found in some of the ascidia, as the pitchers are botanically termed, may have been collect- ed from rains, but in others the mouth of the pitcher is so protected that it is impossible for it to have been derived from this source, and it must be secreted by the leaf itself. Sev- eral plants collect rain water without having proper pitchers to receive it; a notable in- stance of this is the traveller's tree of Mada- gascar (Ravenala Madagascariensiti), the finest of the banana family ; this has very large oval leaves, the sheathing petioles of which are dis- tended at the base, forming a capacious cup into which the water that falls upon the blade of the leaf is conveyed by the channelled mid- rib and petiole ; the thirsty traveller has only to pierce the base of the petiole to obtain a supply of fresh and limpid water. A similar collection of water takes place, though on a much smaller scale, at the base of the leaves of Tillandsia utriculata, a Florida plant of the related pineapple family, in which the base of the leaf is sufficiently dilated to hold sev- eral ounces of water ; this plant being an epi- phyte and found only growing on the trunks of trees, this may be regarded as a provision against drought. Among the pitcher plants proper, our peculiarly North American genus Sarracenia presents in its six species several interesting forms; all these except one are restricted to the Atlantic states near the coast, Northern Pitcher Plant (Sarracenia purpurea). from Virginia southward. The exceptional spe- cies is 8. purpurea, which grows from Flor- ida to Newfoundland and extends westward as far as Minnesota, but west of the Allegha- nies is not found south of Ohio and Illinois ; this was the first species made known, and upon it Tournefort founded the genus, which he dedicated to Dr. Sarrazin of Quebec, who forwarded the plant with a botanical account of it to Europe. The sarracenias are bog-loving perennials, and have tubular leaves in a radical cluster ; the leaves vary much in size as well as in form and color in the different species, and in all are marked by a network of veins ; structurally these pitchers, or trumpets, as they are often called, are regarded as leaves with a very broad petiole, which is joined at the edges to form a trumpet-like tube, the suture where the edges unite being marked by a wing run- ning the whole length ; the proper blade, very small in proportion to the petiole, appears as an appendage at the end of the tube, called