Leaves 8′—12′ long, with slender pubescent petioles and rachis, and 9—13 rarely 19 oblong-lanceolate to ovate acuminate often slightly falcate coarsely serrate leaflets cuneate or rounded at base, coated when they first appear with scurfy pubescence, soon becoming glabrous, or at maturity slightly pubescent on the midrib below, 3′—4′, or those of the lower pairs 1½′—2′ long, and 1′—1½′ wide, thin, yellow-green, with a thin conspicuous yellow midrib and primary veins. Flowers: staminate in slender puberulous or pubescent aments 8′—10′ long; calyx nearly orbicular, long-stalked, pale yellow-green, 5 or 6-lobed, the lobes ovate, acute, hoary pubescent on the outer surface, their bract acute, coated with thick pale tomentum; stamens 30—40, with nearly sessile yellow anthers, and slightly divided connectives; pistillate not seen. Fruit subglobose to slightly ovoid or oblong, abruptly contracted at apex into a short point (_J. elæopyren_ Dode), densely tomentose when half grown, 1′—1½′ in diameter, with a thin husk covered with close rufous pubescence; nut dark brown or black, slightly compressed, usually rather broader than high, or ovoid, rounded or bluntly acute at apex, rounded and sometimes depressed at base, longitudinally grooved with broad deep grooves, thick shelled; seed small and sweet. A tree sometimes 50° high, with a straight trunk occasionally 3°—4° in diameter, or divided at the ground into several large stems, stout branches forming a narrow head, and slender branchlets thickly coated when they first appear with rufous pubescence, becoming red-brown, pubescent or puberulous and marked by many small pale lenticels at the end of their first season and ashy gray the following year. Distribution. Banks of streams in the cañons of central and southern New Mexico and Arizona, and on Oak Creek near Flagstaff, Arizona on the Colorado plateau (_P. Lowell_). 4. Juglans rupestris Engelm. Walnut. [Illustration: Fig. 166]