LATHYRUS.] LEGUMINOS^. 113 



Rootstock short. Stems 1-2 ft., erect, branched, stout or slender. Leaflets 

 f-lf in., nerves diverging ; petiole 1-2 in. ; stipules -J in. Peduncles 

 shorter or longer than the leaves, 2-8-fld. ; pedicels about as long as the 

 calyx; bracts filiform or 0. Flowers | in., livid-purple fading to blue. Calyx- 

 teeth very short, triangular. Pods 2 in., narrow, turgid, rugose, acuminate 

 at both ends, 6-8-seeded, subseptate. Seeds compressed, obtusely angled. 

 DISTRIB. Europe, Caucasus. 



ORDER XXVI. ROSA'CEJE. 



Herbs, shrubs, or trees. Leaves alternate, rarely opposite, simple or 

 compound, stipulate. Inflorescence various. Flowers regular. Calyx 

 superior or inferior ; lobes 5, the 5th next the axis, imbricate in bud. 

 Petals 5, rarely 0, perigynous, often orbicular and concave, claws very 

 short or 0, deciduous, imbricate in bud. Stamens many, rarely 1 or few, 

 inserted with the petals or on the disk, 1-maiiy-seiiate, incurved in bud ; 

 anthers small, usually didymous. Disk lining the calyx-tube. Carpels 1 

 or more, distinct or connate, free or adnate to the calyx-tube ; styles as 

 many, distinct or connate, terminal ventral or basal, stigma simple rarely 

 feathery ordecurrent ; ovules 1, or 2 collateral in each carpel, rarely more, 

 anatropous. Fruit various, a pome, or of one or many drupes aclienes or 

 follicles, rarely a berry or capsule. Seeds ascending or pendulous, alba- 

 men scanty or ; cotyledons plano-convex, radicle short. DISTRIB. 

 Ubiquitous; genera 71 ; species 1,000. AFFINITIES with Leguminosce and 

 Saxifragece. PROPERTIES astringent in Potentillece and Rosece. Prunece 

 and Pomece yield hydrocyanic and malic acids. 



SERIES 1. Ripe carpels not enclosed within the calyx-tube. 

 TRIBE I. PRU'NEJE. Calyx deciduous. Carpel 1; ovules 2, pendulous. 

 Fruit a drupe \. Primus . 



TRIBE II. SPIRJE'JE, Calyx persistent, ebracteolate. Carpels 5 or more ; 

 ovules 2 or more in each carpel, pendulous. Fruit a follicle... 2. Spiraea. 



TRIBE III. RU'BEJE. Calyx persistent, ebracteolate. Carpels many ; ovules 

 2 in each carpel, pendulous. Fruit of many small drupes 3. Rubus. 



TRIBE IY. POTENTH/LE.ffi. Calyx persistent, bracteolate. Carpels 4 or 

 more] ovule 1 in each carpel, ascending. Fruit of 4 or more achenes. 



* Style elongating aft erf. owe ring. 



Leaves simple. Scape 1-fld. Styles of achenes feathery 4. Dryas. 



Leaves pinnate. Stem several-fld 5. Geum. 



** Style not elongating after jlowering . 



Leaves 3-foliolate. Achenes on a large fleshy receptacle 6. Fragaria. 



Leaves 3-many-foliolate. Achenes on a small dry receptacle...?. Potentilla. 



I 



