DICOTYLEDONOUS PLANTS 51 
or oblong, thin-shelled. River bottoms. Rarely native east of the 
Mississippi River, but widely planted for its fruit.* 
2. C. alba, Nutt. SHeLiBark Hickory. A large tree with bark 
sealing off in long plates, young twigs and leaves downy, becoming 
smooth with age. Leaflets 5, the lower ones oblong-lanceolate, the 
upper one longer and obovate, taper-pointed at the apex, narrowed 
to the sessile base. Inner bud-scales becoming large and conspicu- 
ous. Staminate catkins in threes. Fruit globose, husk thick, split- 
ting into four sections, nut white, compressed, 4-angled, pointed, 
thin-shelled. On rich soil. More common N. Wood strong and 
elastic, but not durable when exposed.* 
3. C. sulcata, Nutt. Bic SHELLBARK, Kinc Nut, Butt Nut. A 
tree 70-90 ft. high, with shaggy bark. Leaflets 7 or 9, the terminal 
one nearly sessile. Fruit large, ovoid or nearly so, 4-grooved toward 
the outer end, the husk very thick, nut pointed at each end, 13-2 in. 
long, thick-shelled, with a very sweet kernel]. Wood hard and heavy. 
Common in rich, damp soil W. 
4. C. amara, Nutt. Picgnut, Swamp Hickory. A medium- 
sized tree, with rather smooth bark. Leaflets 7-11, lanceolate or 
oblong-lanceolate. Fruit not large, husk thin, nut globular, with a 
short point, very thin-shelled, kernel extremely bitter. Moist soil, 
common in the Middle States. 
17. BETULACEZ. Brrcn Famiry. 
Trees or shrubs, with alternate, simple, petioled leaves with 
usually deciduous stipules. Flowers moneecious in cylindri- 
eal or subglobose catkins, staminate catkins drooping; flowers 
1-3 in the axil of each bract, calyx none, or membranous 
and 2-4-parted; stamens 2-10, distinct. Pistillate catkins 
drooping, spreading, or erect and spike-like; flowers with or 
without a calyx, ovary solitary, 1—2-celled, ovules 1—2 in each 
cell. Fruit a 1-celled nut or key.* 
I. CARPINUS, L. 
— 
Trees with thin, straight-veined leaves, which are folded 
in the bud. Flowers appearing before the leaves ; staminate 
flowers in slender drooping catkins, sessile at the end of the 
growth of the previous season; stamens 3-12, subtended by 
a bract, filaments forked, anthers hairy. Pistillate catkins 
