ROSACEA, SILVA OF NORTH AMERICA. 27 
PRUNUS ALLEGHANIENSIS. 
Sloe. 
CALYX-LOBES entire, puberulous on the outer, tomentose on the inner surface. Fruit 
usually subglobose, dark blue covered with bloom; stone turgid, acute at the two ends. 
Leaves lanceolate to oblong-ovate. 
Prunus Alleghaniensis, T. C. Porter, Bot. Gazette, ii. 85; Garden and Forest, iii. 428, £. 58. — Watson & Coulter, Gray’s 
Man. ed. 6, 151. 
A small slender tree, occasionally eighteen to twenty feet in height, with a trunk which is some- 
times six or eight inches in diameter, and which divides into numerous erect rigid branches; or more 
often a shrub, usually four or five feet high. The bark of the trunk is dark brown and a quarter of an 
inch thick, the fissured surface broken into thin persistent scales. The branches, when they first appear, 
are coated with pale pubescence; this soon disappears and in their first winter they are dark red and 
rather lustrous, later becoming brown or finally nearly black, and are unarmed or sometimes armed with 
stout spinescent lateral spur-like branchlets, and are covered with minute pale lenticels. The winter- 
buds are a sixteenth of an inch long, and acuminate or obtuse, the accrescent inner scales scarious, 
oblong-acute, two thirds of an inch long, and bright red at the apex. The leaves are lanceolate to 
oblong-ovate, often long-acuminate and finely and sharply serrate with glandular-tipped teeth, and bear 
at the very base of the blade two large rather conspicuous glands; when they unfold they are covered 
with soft pubescence, and at maturity are puberulous on the upper surface, and on the lower surface are 
sometimes quite glabrous with the exception of a few hairs in the axils of the veins, or are covered, espe- 
cially along the broad midribs and conspicuous veins, with rufous pubescence; they are rather thick and 
firm in texture, dark green above and paler below, two to three and a half inches long and two thirds of 
an inch to an inch and a quarter broad, and are borne on slender grooved pubescent or puberulous peti- 
oles which vary from a quarter to a third of an inch in length. The flowers, which appear in May with 
the unfolding of the leaves, are half an inch across when fully expanded, with slender puberulous pedi- 
cels from one half to two thirds of an inch in length, arranged in subsessile two to four-flowered umbels. 
The calyx-tube is narrowly obconic and pubescent or puberulous on the outer surface, with ovate-oblong 
lobes rounded at the apex, scarious on the margins, and coated with pale tomentum on the inner surface. 
The petals are pure white, rounded at the apex and contracted at the base into short claws, and in 
fading turn pink. The filaments and pistil are glabrous. The fruit, which is produced in great quanti- 
ties and often quite covers the branches, ripens in the middle of August; it is borne on stout puberulous 
stems, and is subglobose or slightly oval or pear-shaped, and varies from one third to two thirds of an 
inch in diameter; the skin is thick, rather tough, and dark reddish-purple, covered with a glaucous 
bloom ; the flesh is yellow, juicy, and austere, and adheres to the thin-walled turgid stone which is two 
thirds as thick as broad, from a quarter of an inch to half of an inch long, pointed at both ends, ridged 
on the ventral edge, and slightly grooved on the other. 
Prunus Alleghaniensis is not known to grow spontaneously outside of a small elevated region in 
central Pennsylvania, which extends from the slopes of Tussey’s Mountain in the northwestern part of 
Huntingdon County, across Bald Eagle Mountain and Valley, and over the main range of the Allegha- 
nies into Clearfield and Elk Counties, and has a north and south range of only twenty or thirty miles. 
Tt grows in low moist soil, where it forms shrubby thickets, sometimes of considerable extent, and on the 
