J. nìgra.
2. Jùglans nìgra, L. (Black Walnut.) Leaflets 13 to 21, lanceolate-ovate, taper-pointed, somewhat heart-shaped and oblique at base, smooth above and very slightly downy beneath. Fruit globular, roughly dotted; the thick-shelled nut very rough; ripe in October. A large handsome tree, 50 to 120 ft. high, with brown bark; more common west than east of the Alleghanies; often planted. Wood dark purplish-brown.
J. règia.
3. Jùglans règia, L. (Madeira Nut. English Walnut.) Leaflets 5 to 9, oval, smooth, obscurely serrate. Fruit oval, with a thin-shelled oval nut not nearly so rough as that of Juglans cinerea, or of Juglans nigra. When ripe the husk becomes very brittle and breaks open to let out the nut. Tree intermediate in size, 40 to 60 ft. high, hardy as far north as Boston in the East, but needs protection at St. Louis. It should be more extensively cultivated. Introduced from Persia.
Genus 82. CÁRYA.
Hard-wooded trees with alternate, odd-pinnate leaves having straight-veined leaflets. The leaflets are opposite each other, and the terminal pair and end leaflet are usually much the largest. The sterile flowers are in hanging catkins, the fertile ones minute, forming a large, rounded, green-coated, dry drupe, with a roughened nut having a bony partition. The drupes hang on till frost, when they open more or less and usually allow the nut to drop out. Wood hard and tough.
| * Bark shaggy and scaly; kernel very good. (A.) | ||
| A. Leaflets usually 5 (5 to 7) | 1. | |
| A. Leaflets 7 to 9 | 2. | |
| * Bark rough, deeply furrowed but not shaggy; kernel edible. (B.) | ||
| B. Leaflets 7 to 9, usually 7 | 3. | |
| B. Leaflets 5 to 7, usually 5 | 4. | |
| * Bark smooth; kernel bitter. (C.) | ||
| C. Leaflets 5 to 7, usually 7, smooth | 5. | |
| C. Leaflets 7 to 11, serrate with deep teeth | 6. | |
| * Bark smooth; nut thin-shelled; kernel sweet; leaflets 13 to 15 | 7. | |
