26 BULLETIN 179, U. S. DEPARTMENT OF AGRICULTURE. 
State. It evidently reaches nearly to the coast in the vicinity of 
Savannah, Ga., but is not found in the Coastal Plain of the Carolinas. 
With the possible exception of Prunus pennsylvanica, P. americana 
is the most widely distributed of any of the native species, and it 
appears also to be one of the most variable. In the Eastern States 
it grows mainly in rich alluvial soils, in the Southern States it is. 
frequently met with in the mountain region, but sometimes occurs 
in river swamps, while in the prairie States of the Mississippi Valley 
it is found on bottom lands and sometimes on dry uplands. Toward 
its western limits it is smaller and often assumes even a shrublike 
appearance. Material of the species from the western portion of its 
range indicates a form having leaves usually more glabrous and of 
a lighter green color, with a greater tendency to fold in drying. In 
the East the calyx lobes are usually glandular and minutely toothed 
toward the apex, while west of the Mississippi River the calyx lobes 
are usually, though not always, eglandular and entire. _ There is also 
a tendency for the stone in eastern specimens to be shorter in pro- 
portion to its breadth and more turgid than in western material. 
There are so many exceptions to the constancy of these characters 
in a definite geographical region, however, that it seems unwise, and 
in fact apparently impossible, to distinguish any form, even as a 
subspecies. In southwestern Missouri a-grove was found, the trees 
of which appeared rather different from others in that vicinity. These 
trees were 10 to 15 feet high; leaves oval-lanceolate to lanceolate, 5 
to 7 cm. long, 2 to 3 cm. broad, rather long acuminate at the apex, 
gradually narrowed toward the base, green and glabrous above, pale 
and rather loosely pubescent below; flowers about 12 mm. broad, 
pedicels 6 to 8 mm. long, glabrous, calyx entirely glabrous on the 
outer surface, tube about 2 mm. long, the oblong lobes about as long, 
obtuse, ciliate on the margin, eglandular, hairy within, at least 
toward the base; petals 5 to 6 mm. long, oblong-oval to oblong- 
cuneate; fruit globose. 
Prunus americana was probably the first American species to 
be described botanically, for it is apparently included by Plukenet 
in 1696. It was not named binomially until 1785, when it was 
described by Marshall. So far as known, no types of Marshall’s 
plants are in existence, but there can be little possibility of mistaking 
the identity of his species in this case, and his material doubtless 
came from eastern Pennsylvania. Prunus latifolia was described by 
Moench in the same year in which Marshall’s Arbustrum was pub- 
lished. Moench described his species from material grown from seed 
obtained in America. P. hiemalis was described from ‘‘Canada, 
Virginia et in umbrosis Carolinae.” P. ignota, based on specimens 
collected by C. S. Crandall on the banks of the Cache la Poudre, 
near Fort Collins, Colo., does not differ from the species. 
