220 SYSTEMATIC BOTANY. 



G. TRIACANTHOS (Honey Locust}. Branches armed with stout, most- 

 ly branching, triple thorns ; leaves abruptly pinnate, or bipinnate ; leaflets 

 alternate, oblong-lanceolate, obtuse ; flowers small, white, spicate ; pods 

 long, flat, curved, pendulous. A handsome, thorny tree. June. 



Order XXVIII. ROSACES (Rose Family]. 

 Trees, shrubs, or herbs. Leaves alternate. Stipules usually 

 present. Flowers regular, usually perfect. Sepals 5, rarely less, 

 more or less united, commonly persistent. Petals 5, perigynous, 

 sometimes wanting. Stamens numerous, rarely few, inserted on 

 the calyx, distinct. Ovaries several, or i, often adherent to the 

 calyx-tube, and to each other. Styles distinct, or united. Fruit 

 a drupe, pome, achenium, or follicle. 



f i. Fruit a drupe Prunus. 



f Petals equal Spircea. 

 2. Fruit a follicle-^ 



t Petals unequal Gillenia. 



f Achenia pulpy Rubus. 



3. Fruit 

 achenia 



Achenia 

 I dry- 



Receptacle fleshy Fragaria. 



Recep- 

 tacle 

 dry 



Achenia 

 without 

 long styles 



Achenia izwWaldsteinia. 

 Achenia many Potentilla. 



{ Dry Agrimo- 

 Achenia on the | nia. 

 calyx-tube 4 



( Fleshy Rosa. 



[Achenia with long persistent styles Geum. 

 f 1-5 bony seeds Crat&gus. 



\ 2-5 two-seeded carpels Pyrus. 

 4. Fruit a pome <{ 



3-5 one-seeded carpels Amelanchier. 



[5 many-seeded carpels Cydon ia. 



I. Prunus. Calyx 5-cleft, regular, deciduous. Petals spreading. 

 Stamens 25-30. Drupe globose, fleshy, destitute of bloom, y. 



1. P. CERASUS (Ctierry). Leaves oblong-ovate, hairy beneath ; flowers 

 large, white, in umbels ; drupe ovoid. Cultivated, and esteemed for its de- 

 licious fruit. May. 



2. P. AMERICANA (Wild Plum}. Leaves oval, varying to ovate, doubly 

 serrate ; flowers white, in sessile umbels ; drupe roundish-oval, red and 

 orange, very smooth, sweet and pleasant, with yellow pulp, and a thick, 

 tough skin. A straggling shrub, 8-10 feet high, with somewhat thorny 

 branches. May. 



3. P. PERSICA (Peach). Flowers rose-colored ; calyx bell-shaped. Fruit 

 globular, with thick pulp. A small tree, largely grown for its excellent fruit 



