440 WALNUT 25 ft. in circumference. The leaflets are ovate- lanceolate, somewhat heart-shaped or unequal at base, smooth above and minutely downy be- Black Walnut (Juglans nlgra) Tree near Roslyn, Long Wand, N. Y. low ; the fruit is spherical, the surface marked by rough dots, greenish yellow when ripe, but soon turning black; the round, slightly flat- tened nut has a deeply corrugated, hard shell, with an oily kernel, which soon becomes rancid. The wood of the black walnut is hard, fine- grained, and durable, and takes a fine finish. When first cut it is purplish brown, but with age it turns very dark, even almost black. The husks of the fruit are used in dyeing, and an oil may be expressed from the kernels. On account of its rapid growth and the value of its timber, this is largely planted in the treeless portions of the western states ; the nuts, gath- ered into heaps, are covered with straw and earth to keep out rain, and in spring are plant- ed where the trees are to stand. The closely related J. cintrea is described under BUTTER- NUT. The only remaining species, the rock walnut (J. rupestri*), is found in western Texas, New Mexico, and Arizona; it is a shrub, or sometimes a tree 30 ft. high, with numerous curved leaflets, and a globose fruit with a thin pulp, enclosing a nut about half an inch in diameter, with a remarkably thick shell, the kernel being only as large as a pen. The Eu- ropean walnut (/. regia), also called in this country English walnut, is a native of Asia, and probably of Greece. It grows abundantly throughout Europe, but in this country it rare- ly ripens its fruit. It forms a large tree ; the leaflets are fewer than in our black walnut, oval, smooth, and with entire margins; the fruit is oval, the husk, unlike that of our spe- cies, thin and brittle, and readily breaking away from the smoothish, thin-shelled nut. In Eu- rope, where much attention is given to its cul- tivation, about a dozen named varieties are known, distinguished by the abundance, size, and shape of the fruit, the thinness of the shell, and quality of the kernel ; these are propagated by grafting upon seedling stocks ; one dwarf variety, called prc&parturiew, produces fruit in three or four years from seed, a peculiarity that is continued by the seed ; the double walnut, the noyer d bijoux of the French, is cultivated for its large nuts, the shells of which are con- verted into boxes to hold a pair of gloves, jew- elry, &c. The sap of the tree (like that of our species) contains sugar, and has been used in some countries as a source of that product; it is sometimes concentrated and fermented to make walnut wine. The wood, especially from trees grown upon poor soil, is valued for cabi- net work, though inferior in beauty to black walnut. The fruit when partly grown, and still so soft that a pin will pass readily through it, is used for pickling and to make walnut catsup ; our butternut makes an excellent sub- stitute. In Europe the nuts are esteemed only when fresh; those which are to be kept are mixed with layers of sand in jars, and buried. In countries where the trees abound, large quantities of the nuts are pressed for their oil ; for the finest the nuts are cracked, and the thin woody partitions carefully separated from the kernels, which are ground .and pressed ; this product is used for food, the same as olive oil. European Walnut (Juglans regia). A second pressing, after heating the residue, is used as a painter's oil, which is also obtained by heating the nuts at the first pressing if
