132 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
ADDITIONAL SPECIMENS EXAMINED: Mogollon-Magdalena Road, in the Mogollon 
Mountains, about 15 miles east of Mogollon, August 8, 1900, Wooton. 
AMYGDALACEAE, 
PADUS. 
Since all but one of our seven species of Padus appear to be new 
it seems desirable to publish a key to them along with the descrip- 
tions. 
KEY TO THE NEW MEXICAN SPECIES. 
Calyx persistent in fruit. 
Young branches densely tawny-pubescent; young fruit 
pubescent ~---------------------_~__----_--- eee P.rufula, 
Young branches and fruit glabrous____~_-~-_------ P, virens. 
Calyx deciduous soon after anthesis. 
Plants glabrous throughout___--_--_--__-____-__--- P, meianocarpa? 
Plants pubescent on the peduncles, petioles, and lower sur- 
face of the leaves. 
Leaves not glaucous beneath at maturity, of about the 
same color on both surfaces___-----.----____ P. punricea, 
Leaves whitish beneath at maturity. 
Pedicels longer than the fruit, slender; seeds 8 to 
10 mm. in diameter___._-----_-__________ P. mescaleria. 
Pedicels shorter than the fruit, stout; seeds 7 mm. 
in diameter or less. 
Pedicels glabrous; racemes slender: leaves 
elliptic, narrowed at the base; buds 
narrowly lanceolate in outline________ P. calophylla, 
Pedicels pubescent; racemes stout; leaves ob- 
long’ to ovate or obovate, rounded to 
subcordate at the base; buds ovoid__ P. valida. 
Padus rufula Wooton & Standley, sp. nov. 
Branches slender, grayish brown, with numerous small, gray lenticels; 
young branches densely soft-pubuescent with reddish brown hairs; petioles 
pubescent, slender, one-fourth as long as the blades or less; leaf blades thin, 
elliptic, acute, 40 or 50 mm. long, acute at the base, finely and very sharply 
serrate, dull green and glabrous above, pale beneath, glabrous except for an 
abundant persistent, tawny tomentum along the midvein; racemes slender, 
many-flowered, pubescent at the base, glabrous above; pedicels stout, 4 mm. 
long or less; flowers not seen; hypanthium and sepals persistent; fruit sessile 
in the hypanthium, globose, 8 to 10 mm. in diameter, pubescent when young, 
glabrate at maturity. 
Type in the U. 8. National Herbarium, no. 563898, collected on the West 
Fork of the Rio Gila, August 6, 1900, by E. O. Wooton. 
ADDITIONAL SPECIMENS EXAMINED: NEw Mexico—Mogollon Mountains, August, 
1881, Rusby 119. Arizona—Santa Rita Mountains, 1881, C. G. Pringle. 
This is one of the most distinct species of the genus. It is related to P. 
salicifolia of Mexico, but is distinguished at once by the abundant tomentum 
of the leaves, the densely pubescent branchlets, and the pubescent fruit. 
* Padus melanocarpa (A. Nels.) Shafer in Britt. & Shaf. N. Amer. Trees 504. 
1908. 
