ROSACER. SILVA OF NORTH AMERICA. 13 
CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES. 
Prunus. Flowers in fascicled umbels; fruit often slightly two-lobed by a ventral groove; leaves 
conduplicate or convolute in vernation. 
Leaves conduplicate in vernation. 
eee red or orange-colored, destitute of bloom. 
Calyx-lobes glandular-serrate, glabrous on the inner surface; stone compressed ; 
leaves broadly oblong-ovate to obovate; petioles biglandular . . . . . . 1. P. nigra. 
Calyx-lobes entire, pubescent on the inner surface; stone turgid; leaves oval or 
slightly obovate; petioles usually eglandular. . . . . - + + ss s 2. P. AMERICANA. 
Calyx-lobes glandular-serrate, pubescent on the two surfaces; stone turgid, com- 
pressed at the two ends; leaves ovate-lanceolate, acute ; petioles glandular . 3. P. HORTULANA. 
Calyx-lobes glandular-ciliate, glabrous; stone turgid; leaves lanceolate to oblong- 
lanceolate; petioles biglandular. . . . . . . - »- 2 + s+ «+ ee @ 4. P. ANGUSTIFOLIA 
Fruit blue, covered with a glaucous bloom. 
Calyx-lobes entire, puberulous on the outer, tomentose on the inner surface; stone 
turgid, acute at the two ends; leaves lanceolate to oblong-ovate; petioles eglan- 
Giitie, 6 G6 5 60 606 506 915 6 666 6 6 6 5 Ge oi Ce Ie Nii imme, 
Leaves convolute in vernation. 
Fruit red or yellow, nearly destitute of bloom. 
Calyx-lobes pubescent or puberulous, with ciliate margins; stone flattened or 
turgid, pointed at the two ends; leaves broadly ovate to orbicular; petioles 
eplandular). 29. . 9. . : op he ee ee oe 0. . BUBCORDATAT 
Fruit dark blue or black, covered ak a ce oe 
Calyx-lobes entire, glabrous or puberulous on the outer, fone on the inner 
surface; stone slightly compressed, acute at the two ends; leaves ovate-lance- 
olate to oblong; petioles eglandular. . . . eae te cued. © ele) a bs UMBELUATAS 
Crrasus. Flowers fascicled or corymbose; fruit globular ; aes cE ETn in vernation, 
Calyx-lobes obtuse, entire ; stone oblong-globular ; leaves a -lanceolate; pe- 
mds ako? 2° 6° Gc 5 6 6 4 6 Gob 65 oe er. . 28k. PENNS LY ANICA. 
Calyx-lobes rounded or sometimes emarginate at the apex; stone ovoid, acute at 
the two ends; leaves oblong-obovate to oblanceolate . . . . . . . .- . 9 P. uMARGINATA. 
Papus. Flowers racemose on leafy branches of the year; fruit globular; stone cylindrical; 
leaves conduplicate in vernation. 
Calyx-lobes deciduous ; stone oblong-ovate; pointed at the apex; leaves broadly 
oval or oblong-obovate, usually abruptly acuminate. . . - BG . . 10. P. Vireinrana, 
Calyx-lobes persistent on the ripe fruit; stone oblong-obovate ; Hee sting or : 
lanceolate-oblong, usually gradually acuminate . . . - . . 11. P. szROTINA. 
Lavrocerasus. Flowers racemose, from the axils of persistent leaves ‘of a previous year ; 
fruit globose or slightly two-lobed ; leaves conduplicate in vernation. 
Calyx-lobes rounded, with undulate margins; stone broadly ovate, cylindrical ; 
leaves oblong-lanceolate, entire, or rarely remotely spinulose-serrate . . . . 12. P. CAROLINIANA. 
Calyx-lobes acute, with laciniate margins ; stone ae leaves ellip- 
tical to oblong-ovate, entire . . . - b Se gy hon. SPH AROCARE AY 
Calyx-lobes acute, entire; stone ovate, slightly Soe ae ovate to lan- 
ceolate-acuminate, coarsely spinulose-toothed or rarely entire . . . . . . 14, P. micrrona. 
