410 
1. P. occidentalis L. Very large tree, 18 to 54m. high: leaves mostly truncate at 
base, angularly sinuate-lobed or toothed, the short lobes sharp pointed: fertile 
heads solitary, hanging on long peduncles.—Alluvial banks, extending to the Nueces 
and the Pecos. 
2. P. Wrightii Watson. Leaves subtomentose beneath, very acutely and deeply 
5 to 7-lobed, the lower lobes projecting backwards and forming a deep sinus: 
racemes not exceeding the leaves: fertile heads 3, 16 to 20 mm. in diameter: nutlets 
truncate above and tubereled with the short base of the style: receptacle densely 
hairy and fruit-bearing over nearly the entire surface —Valleys trom the San Pedro 
(Arizona) to southwestern New Mexico and extending into Mexico; probably in 
southwestern Texas, 
JUGLANDEA. (WALNUT FAMILY.) 
Small family of important trees, with alternate pinnate leaves, no 
stipules, mona@cious flowers, the sterile in catkins and with an irregular 
valyx adnate to the bract; the fertile solitary or in a small cluster or 
spike and with a regular 3 to 5-lobed calyx adherent to the incompletely 
2 to 4-celled but only 1-ovuled ovary, and the dry crustaceous or bony- 
shelled drupaceous fruit containing a large 4-lobed orthotropous seed. 
1. HICORIA Raf. (Hickory.) 
Fine timber trees, with very hard and tough wood, the sealy buds 
(in spring) usually putting forth both kinds of flowers, the sterile 
flowers below in slender lateral catkins (with the naked calyx adherent 
to the bract and unequally 2 or 3-parted, 3 to 10 stamens, and the free 
filaments short or none), the fertile 2 to 5 in a short cluster or spike on 
a peduncle terminating the shoot of the season (with 4-toothed calyx, 
2 to 4 large papillose sessile stigmas, and fruit with a 4-valved firm and 
at length dry exoearp |involucre] falling away from the smooth 
endocarp). . 
* Sterile catkins fascicled (no common peduncle or sometimes avery short one) from sepa- 
rate lateral scaly buds near the summit of the shoots of the preceding year: bud-scales 
Sew: fruit elongated-oblong: the thin-shelled nut 2-celled below: seed sweet: leaflets 
short-stalked, numerous, 
1. H. Pecan (Marsh.) Britton. (PECAN-NUT.) A large tree (18 to48 m. high), with 
delicious nuts, minutely downy, becoming nearly smooth: leaflets 13 to 15, oblong- 
lanceolate, tapering gradually to a slender point, falcate, serrate: nut olive-shaped. 
(Juglans Pecan Marsh. Carya oliveformis Nutt.)—Extending from the Mississippi 
States to the streams of central and southwestern Texas, as far west as Fort Concho, 
H. Texana Le Coute is referred here, but Dr. Britton thinks it may prove distinct. 
** Sterile catkins in threes (rarely more) on a common peduncle from the axil of the inner 
scales of the common bud, therefore al the base of the shoot of the season, which, then 
bearing 3 or 4 leaves, is terminated by the fertile flowers: fruit globular or oval: nut 
4-celled at base: leaflets sessile or nearly so. 
+ Hull splitting promptly into 4 more or less thick and when dry hard woody valves: seed 
sweet and delicious. (The “hickory-nuts” of the market.) 
2. H. ovata (Mill.) Britton. (SHELL-BARK or SHAG-BARK HICKORY.) Large tree, 
with bark of trunk exfoliating in rough strips: inner bud-scales becoming large and 
conspicuous, persistent till the flowers are fully developed: leaflets 5 or 7, minutely 
