8. COWANIA D. Don.
Trees or shrubs with scaly bark and rigid terete branchlets. Leaves alternate, simple, lobed or rarely linear, subcoriaceous, straight-veined, glandular-dotted on the upper surface, tardily deciduous or persistent, short-petiolate; stipules adnate to the base of the petiole. Flowers solitary at the end of short lateral branches; calyx-tube turbinate, persistent, the limb 5-lobed, deciduous, the lobes imbricated in the bud; disk thin, adnate to the tube of the calyx, its margins thickened; petals 5, obovate, spreading, larger than the calyx-lobes; stamens numerous, inserted in two rows in the mouth of the calyx-tube, incurved, persistent; anthers peltate, eglandular, 2-celled, opening longitudinally; carpels 5—12, inserted in the bottom of the calyx-tube, free, villose, 1-celled; style short, villose, stigma simple, filiform; ovule solitary, ascending; raphe linear, dorsal; micropyle inferior. Fruit composed of 5—12 1-celled ellipsoidal akenes, included in the tube of the calyx, and tipped with the much elongated persistent styles covered with long white hairs; seed filling the cavity of the carpel, linear-obovoid, erect; hilum basal, minute; testa membranaceous; albumen thin; cotyledons oblong, radicle inferior.
Cowania is confined to the dry interior region of the United States and Mexico. Three species can be distinguished; of these the type of the genus, Cowania mexicana D. Don, sometimes attains the size and habit of a small tree. The genus was named in honor of James Cowan (died 1823), an English merchant who traveled in Mexico and Peru and sent plants to England.
1. [Cowania mexicana] D. Don.
Cowania Stansburiana Torr.
Cowania Davidsonii Rydb.
Leaves short-petioled, cuneate, revolute on the margins, 3 or rarely 5-lobed above the middle, the lobes linear, entire or slightly divided, coriaceous, dark green above, hoary-tomentose below, ⅓′—½′ long, tardily deciduous or persistent until spring; leaves on vigorous shoots and on flower-bearing branchlets occasionally linear and entire; stipules ciliate on the margins, united below and adnate to the short persistent petiole, free above the middle and acute at apex, persistent and becoming woody on the flower-bearing branchlets. Flowers appearing in early spring, 1′ in diameter; calyx-tube more or less tomentose and covered with rigid glandular hairs, the lobes rounded at apex, hoary-tomentose; petals broad-obovate, rounded and emarginate at apex, cuneate and short-stipitate below, pale yellow or nearly white. Fruit ripening in October, about ¼′ long and as long as the calyx-tube, the elongated style often 2′ in length.
A tree, occasionally 20°—25° high, with a tall trunk 6′—8′ in diameter, short spreading branches forming a narrow head, and slender rigid branchlets red and glandular during their first season, becoming dark reddish brown and glabrous the following year. Bark of the trunk pale gray, separating freely into long narrow thin loosely attached plates; more often a shrub with spreading stems often only a few feet tall.
Distribution. Dry rocky slopes and mesas, usually at altitudes between 6000° and 8000°; northern Utah and central Nevada, through Arizona and western New Mexico to northern Mexico; common and probably of its largest size near the southern rim of the Grand Cañon, and on the lower slopes of the San Francisco Mountains, Arizona.