ROSE FAMILY 117 



HypantMum wheel-shaped; petals narrowly linear; 

 pistils 2. 11. COMAKELLA. 



Stamens inserted very near the base of the receptacle on 

 a more or less evident annular thickening. 



12. POTBNTIUUA.. 

 Style lateral; ovules ascending and amphitropous. 

 Achenes glabrous; herbs. 



Achenes numerous ; stamens about 20. 

 Leaves odd-pinnate. 



Heceptaclp not enlarged in fruit; petals yellow, 

 obtuse or retuse; leaves interruptedly pin- 

 nate. 13. Argentina. 

 Receptacle somewhat enlarged in fruit, becom- 

 ing spongy; petals red, acute or acuminate; 

 leaves regularly pinnate. 



14. CoMAKmi. 

 Leaves trifoUolate; receptacle muph enlarged and 

 usually red in fruit, pulpy; petals white or 

 pinkish. 15. Fragahia. 



Achenes 10-15; stamens 5; leaves trifoUolate. 



16. SIBBALDIA. 

 Achenes hairy; shrubs; style club-shaped; leaves pinnate; 

 petals (in ours) yellow. 17. Dasiphora. 



Style nearly basal; ovules ascending or nearly erect, orthotropous. 

 Stamens and pistils numerous; bractlets present; leaves piu- 



nate. 18. Drymocaiiis. 



Stamens 5; bractlets wanting; leaves twice or thrice ternate. 



19. Chamaerhodos. 

 Style not articulate to the ovary; inflorescence spicate, racemose 

 or paniculate; hypanthium indurate, closely investing the 

 achenes in fruit. 

 Hypanthium not prickly; petals lacking. 



Perennials, with rootstocks; stigmas muricate-papillose; leaf- 

 lets toothed. 20. Sanguisorba. 

 Annuals or biennials, with taproots; stigmas brush-like; 1 eaf- 

 lets pectinate-pinnatifld. 21. PoTERlDltTM. 

 Hypanthium prickly; petals present; prickles of the hypanthium 

 hooked. 22. Agrimonia. 

 Disk at the mouth of the hypanthiiun produced into a cylindric tube, 

 separating the stamens from the pistils ; shrubs with opposite leaves 

 and branches. 23. Coleogyne. 

 b. Seeds inserted at the proximal end of the ovary, i. e., perfectly basal; 

 radicle inferior. 

 Styles wholly deciduous. 24. Waldsteinia. 

 Styles partly or wholly persistent. 



Hypanthium hemispheric, campanulate or turbinate, persistent. 

 Pistils several or many. 



Flowers 8-10-merous; low depressed imdershrubs with cren- 



ate or entire leaf-blades. 25. Dryas. 



Flower usually 5-merous. 



Sepals valvate; perennial herbs, with rootstocks; leaves 

 pinnate; bractlets present. 

 Style conspicuously bent and distinctly geniculate 

 above, the upper hairy portion readily deciduous. 

 26. GEUM. 

 Style neither conspicuously bent nor distinctly geni- 

 culate, the upper glabrous portion persistent 

 or tardily deciduous. 

 Styles conspicuously elongating in fruit, plumose 



below. 27. SlEVBRSIA. 



Styles not much elongating in fruit, not plumose. 



28. ACOMASTYLIS. 



Sepals imbricate in bud; shrubs; leaves dissected into 

 narrow lobes. 

 Bractlets present; pistils numerous. 



29. FAIiLUGIA. 

 Bractlets wanting; pistils few. 30. Cowania. 



Pistils usually solitary ; shrubs with 3-cleffc leaves. 



31. PXIRSHIA. 

 Hypanthium salver-shaped, the Umb deciduous; the tube persistent 

 and closely investing the fruit; shrubs. 32. Cercocarpus. 

 o. Fraits of more oi less fleshy drupelets; ovules 2, collateral. 



Styles club-shaped; stigmas slightly 2-lobed; receptacle flat; unarmed shrubs 

 with exfoUattng bark and simply dlgitately ribbed and lobed leaves. 

 Drupelets capped by a hard pubescent cushion; styles glabrous. 



33. Eubacer. 

 Drupelets without cushion; styles hairy. 34. Oreobatus. 



Styles flJiform, glabrous; stigmas capitate; receptacle convex, hemispheric or 

 nipple-shaped; drupelets without cushion; leaves in most species compound 

 and stem prickly or bristly. 35. RUBUS. 



II. Carpels enclosed ia the hypanthium which becomes fleshy in fruit. 



36. ROSA. 



