132 DUDLEY MEMORIAL VOLUME 



Sandy region of Llano and Mason Co., I. Reverchon, May, 1885. Between 

 Laredo and Be jar, Berlandier. 



Without locality, Lindheimer, No. 236, 1844, Drummond. Hall, No. 

 189, 1872. Chas. Wright, 1848. 



AMYGDALUS MICROPHYLLA H. B. & K. 

 Amygdalus microphylla H. B. & K. Nov. Gen. & Sp. PI. 6: 243. t. 564. 



1823. 

 Prunus microphylla Hemsl. Biol. Centr. Am. Bot. 1: 368. 1879-88. 



Leaves with petioles about 1 mm. long, oblong-oval to oblong-oblanceo- 

 late, 10 to 15 mm. long, 3 to 6 mm. broad, glabrous on both surfaces at matur- 

 ity but when immature often sparingly pubescent, narrowed toward the base, 

 obtuse at the apex, the margins crenate-dentate and glandular when young, 

 the glands in age remaining as callous mucronate-like points. Flowers ap- 

 pearing with or before the leaves on very short lateral spurs, one to three on 

 each spur, the pedicels pubescent and 1 mm. or less long; calyx turbinate, 

 about 3 mm. long, glabrous, the lobes 1 mm. long, obtuse and furnished with 

 a few marginal glands; petals oval or obovate, obtuse, 1.5 mm. long and 1 

 mm. broad. Fruit in dried specimens about 12 mm. long, 9 mm. in diameter, 

 oblong-ovoid, rounded at the base, terminated at the apex by a slight mucro- 

 nate-like point; the exocarp dry and pubescent, dehiscent along the ventral 

 side; stone about 10 mm. long, 8mm. broad, slightly winged on the ventral 

 side and with an indistinct groove along the dorsal edge, the surface smooth. 



A small shrub with rather rigid branches and more or less spinescent 

 branchlets, the bark of the young growth light gray and pubescent but be- 

 coming dark gray with age. The species was originally described from 

 Mexico on dry hills between Pachuca and Moran at 7,800 feet altitude. It 

 seems to have been rarely collected, as very little material is to be found in 

 herbaria, either in Europe or America. 



Specimens examined: Mexico; chiefly in the region of San Luis Potosi, 

 6,000 to 8,000 ft. alt., C. C. Parry and E. Palmer, No. 221, 1878. Prope 

 El Gigante, Hartweg, No. 1602. 



AMYGDALUS MINUTIFLORA (Engelm.) W. F. Wight. 



Prunus minutiflora Engelm.; Gray, Bost. Journ. Nat. Hist. 6: 185. 1850. 

 Cerasus minutiflora Gray, PL Wright, pt. 1. 68. 1852. 



Leaves oblong-oval, narrowed toward the 2 to 3 mm. long petiole and 

 rounded at the apex, 7 to 20 mm. long, 5 to 8 mm. broad, pale below and 

 glabrous on both surfaces, the margins sometimes slightly revolute, entire or 

 occasionally irregularly toothed, glandless. Flowers appearing with the 

 leaves in February or March on short lateral spurs, sessile or very nearly so, 



