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IOWA ACADEMY OF SCIENCES. 
THE JUGLANDACEAE OF IOWA. 
BY T. J. AND M. F. L. FITZPATRICK. 
Juglandaceae Lindl. Nat. Syst. Ed. 2, 180, 1836. 
WALNUT FAMILY. 
The walnut family comprises six genera and about 35 
species. Only two genera occur in Iowa, namely, Juglans 
(Walnut) and Hicoria (Hickory), and these two genera are 
represented by two and five species respectively. From an 
economic point of view the species are valuable and con- 
sequently have been largely utilized until but few speci- 
mens of the older forest remain. The younger growth is 
hardy and will, if spared, eventually yield fair returns. 
In general terms the walnut family includes trees with 
alternate pinnate exstipulate (sometimes stipulate in the 
bud) leaves and monoecious bracteolate flowers. The stam- 
inate flowers are in long-drooping aments with an irreg- 
ular calyx adnate to the bract and three to many stamens. 
Pistillate flowers are solitary or clustered with a regular 3-5- 
lobed calyx adherent to the partially 2-4-celled l : ovuled 
ovary; styles 2; fruit a drupe with a fibrous or woody husk 
and a large 2-4-lobed seed. 
Juglans. Husk indehiscent; nut furrowed. 
Hicoria. Husk 4-valved, dehiscent; nut smooth or angled. 
Juglans nigra L. Sp. PI. 997. 1753. Black Walnut. A 
tree, 50-100 feet or more high, with furrowed strong- 
scented brown bark, wood purplish brown, pith in trans- 
verse plates, young twigs and petioles puberulent, becom- 
ing glabrous with age, and odd-pinnate leaves. Leaflets 
nearly sessile, serrate, 11-23, ovate-lanceolate, acuminate, 
mostly glabrous above, pubescent beneath, base sub-cordate 
or unequal; fruit spherical, 4-celled at the base. 
