AMYGDALACEAE. 157 



cium of a single carpel, or rarely of 2 or 3 carpels. Ovary 1-celled : style 

 entire. Fruit a drupe. 



Flowers sessile or nearly so : ovary, and drupe, pubescent ; stone coarsely wrinkled 

 and pitted. 1. Amygdalds. 



Flowers manifestly pedicelled : ovary, and drupe, glabrous ; stone 

 neither wrinkled nor pitted. 

 Flowers in corymbs or clusters from tlie branches of the pre- 

 ceding year, before the leaves. 2. Prunus. 

 Flowers in racemes terminating branches of the year, after 



the leaves. 3. Padus. 



1. AMYGDAIiUS L. Shrubs or trees. Leaves very strongly impregnated 

 with prussic acid. Flowers sessile or short-pedicelled. Corolla mostly pink. 

 Drupe velvety-pubescent, the stone wrinkled and pitted. — Peach. 



1. A. Persica L. Tree: leaf -blades narrowly elliptic to lanceolate, or rarely 

 oblong-obovate, shining, sharply serrate: petals pink, 8-20 mm. long: drupes 

 subglobose or oblong, 4-10 cm. long, grooved on one side, velvety. — Common, 

 on roadsides and in woods and thickets. — Nat. of Old World. — Spr. — 

 Common-peach. 



2. PBUNUS [Tourn.] L. Shrubs or trees. Leaves sometimes slightly 

 impregnated with prussic acid. Flowers in corymbs or umbel-like clusters, 

 relatively long-pedicelled. Corolla mostly white. Drupes usually glabrous and 

 glaucous, the stone smooth or nearly so. — Spr. — Plum. Cherry. 



Leaves conduplicate in vernation. 



Flowers small ; corolla less than 13 mm. wide. 



Leaf-blades narrow, cuneate or narrowed at the base, the coarse teeth not 

 glandular in the sinuses. 

 Leaf-blades of an oblong-spathulate type : inflorescence umbel-like : shrub. 



1. P. cuneata. 

 Leaf-blades of an oblong-lanceolate type : inflores- 

 cence corymbs : tree. 2. P. pennsylvanica. 

 Leaf-blades broad, rounded or subcordate at the base, 



the fine teeth glandular in the sinuses. 3. P. Mahaleh. 



Flowers large ; corolla over 17 mm. wide. 



Leaves glabrous : inner scales of the flowering buds 



broad, not spreading : drupe sour. 4. P. Ccrasus. 



Leaves pubescent : inner scales of the flowering buds 



narrow, spreading : drupe sweet. 5. P. Avium. 



Leaves convolute in vernation. 6. P. americana. 



1. P. cuneata Eaf. Spreading glabrous shrub 3-12 dm. tall: leaf -blades 

 oblong, oval, or somewhat obovate, 3-S cm. long, sometimes acute at both 

 ends, cuneate at the base, glaucous beneath, rather coarsely serrate with ap- 

 pressed teeth: flowers in clusters: pedicels 1-1.5 cm. long: sepals oval or 

 orbicular, toothed: petals 4-5 mm, long, rather slender-clawed: drupes sub- 

 globose, 8-10 mm. in diameter. — S. — Eare, in swamps. — Schists, serpentine. 



2. P. pennsylvanica L. f. Small glabrous tree: leaf -blades thinnish, oblong- 

 elliptic to nearly oval or lanceolate, 8-15 cm. long, acuminate at the apex, 

 doubly serrate: flowers in lateral clusters: pedicels slender, 1-2.5 cm. long, or 

 3 cm. long at maturity: sepals ovate-oblong, entire: petals 4.5-5.5 mm. long, 

 very short-clawed : drupes globose, 4-7 mm. in diameter, red, without bloom, 

 with thin sour flesh: stone subglobose, or slightly elongate. — E. Rare, on 

 hillsides, near Beartown. — Quartzite. — Wild red-cherry. Bird-cherry. 

 Fire-cherry. Pigeon -cherry. 



3. P. Mahaleb L. Shrub or small glabrous tree: leaf -blades ovate, 2-5.5 cm. 

 long, abruptly pointed, finely serrate, rounded, truncate, or subcordate at the 

 base, slightly paler green beneath than above: flowers in corymbs: pedicels 

 1.5-2.5 cm. long: sepals oblong, entire: petals 5-6 mm. long, not clawed: 

 drupes globose or ovoid-globose, 7-9 mm. long, reddish-black. — M. Eare, on 

 cliffs of the Conestoga creek above Lancaster. Nat. of Eu. — Perfumed- 

 cherry. Mahaleb. 



