38 BULLETIN 179, U. S. DEPARTMENT OF AGRICULTURE. 
calyx campanulate, sparingly hairy on the outer surface, the tube 
about 2 mm. long, the lobes oblong or ovate-oblong and obtuse, 1.5 
mm. long, the margin glandular, usually rather strongly pubescent 
within, at least toward the base, apparently erect or spreading 
at anthesis; petals obovate to oblong-obovate, 4 to 6 mm. long, 2.5 
to 3 mm. broad, narrowed toward the base or sometimes more 
abruptly contracted to a claw, entire or erose toward the apex. Fruit 
ripening in August or early September, globose or subglobose, 1.5 to 
2 cm. in diameter, usually yellow overlaid with crimson on one side 
or sometimes golden yellow with whitish dots, rarely entirely red, 
bloom thin or wanting, flesh yellow and rather firm, quality usually 
poor, but occasionally good; stone oblong (Pl. X, figs. 13 to 22), 
11 by 7 by 5 mm. to 13.5 by 10 by 7 mm., pointed at each end or 
sometimes somewhat truncate at the base and rounded, but with an 
abrupt point at the apex, irregularly grooved and ridged near the 
ventral edge, indistinctly grooved along the dorsal edge, the surface 
smooth or obscurely reticulate. 
Prunus reverchonu is a shrub usually 2 to 6 feet high; the bark of 
the stem is gray, while that of the young twigs is chestnut or dull 
reddish chestnut, turning to a dull gray the second year, or rarely 
becoming grayish the first year; lenticels small, round, and lighter 
colored. 
The species (fig. 2) forms very dense thickets on the black upland 
soils and in the rich bottom lands along streams from Limestone 
Gap and the vicinity of the False Washita in southern Oklahoma 
southward to the Colorado in Texas. It probably does not occur 
east of the ninety-sixth meridian, but its western limits are not 
known. It has been collected along the Little Wichita, in Clay 
County, on hills near the Concho River, and in Lampasas County. 
Foliage closely resembling this has also been collected in the vicinity 
of Fort Davis, in western Texas, but without flowers or fruit the 
specimen can not be definitely referred to this species. 
Prunus reverchoni is closely related to P. rivularis and is sometimes 
difficult to distinguish in the herbarium from that species. Addi- 
tional material and study in the field may require it to be ranked 
as a subspecies of the latter. The apparent differences are its more 
branching and less slender stems, trough-shaped leaves, later ripening 
fruit, and more pointed stone. It is generally regarded as of little 
value horticulturally, but its adaptability to limestone soils and 
ability to withstand severe drought may make it of value as a dwarf 
stock, if its habit of suckering is not too great an objection. Thesmall 
stone and the fact that occasional thickets are found producing fruit of 
fair quality suggest also that the fruit should not be entirely neglected. 
One thicket on the Little Wichita River, west of Henrietta, Tex., 
