_Juglans_, from Jupiter and glands, is the classical name of the Walnut-tree.
CONSPECTUS OF THE NORTH AMERICAN SPECIES.
Fruit racemose; nut 4-ribbed at the sutures with smaller intermediate ribs, 2-celled at the base; heartwood light brown; leaflets 11—17, oblong-lanceolate. 1. J. cinerea (A, C). Fruit usually solitary or in pairs; nut without sutural ribs, 4-celled at the base; heartwood dark brown. Nuts prominently and irregularly ridged with often interrupted ridges; leaflets 15—23, ovate-lanceolate. 2. J. nigra (A, C). Nuts more or less deeply longitudinally grooved. Nuts up to 1½′ in diameter; leaflets 9—13, rarely 19, oblong-lanceolate to ovate, acuminate, coarsely serrate. 3. J. major (F, H). Nuts not more than ¾′ in diameter. Leaflets 17—23, narrow-lanceolate, long-pointed. 4. J. rupestris (C). Leaflets 11—15 or rarely 19, oblong-lanceolate, acute or acuminate, the lower often rounded at the apex. 5. J. californica (G). Nuts obscurely or not at all grooved, up to 2′ in diameter; leaflets 15—19, ovate-lanceolate to lanceolate, long-pointed. 6. J. Hindsii (G).
Leaves 15′—30′ long, with stout pubescent petioles, and 11—17 oblong-lanceolate acute or acuminate leaflets 2′—3′ long, 1½′—2′ wide, finely serrate except at the unequal rounded base, glandular and sticky as they unfold, at maturity thin, yellow-green and rugose above, pale and soft-pubescent below; turning yellow or brown and falling early in the autumn. Flowers: staminate in thick aments 3′—5′ long; calyx usually 6-lobed, light yellow-green, puberulous on the outer surface, ¼′ long, its bract rusty-pubescent, acute at apex; stamens 8—12, with nearly sessile dark brown anthers and slightly lobed connectives; pistillate in 6—8-flowered spikes, constricted above the middle, about ⅓′ long, its bract and bractlets coated with sticky white or pink glandular hairs and rather shorter than the linear-lanceolate calyx-lobes; stigmas bright red, ½′ long. Fruit in 3—5 fruited drooping clusters, obscurely 2 or rarely 4-ridged, ovoid-oblong, coated with rusty clammy matted hairs, 1½′—2½′ long with a thick husk; nut ovoid, abruptly contracted and acuminate at apex, with 4 prominent and 4 narrow less conspicuous ribs, light brown, deeply sculptured between the ribs into thin broad irregular longitudinal plates, 2-celled at the base and 1-celled above the middle; seed sweet, very oily, soon becoming rancid.