ROSACEA. 167 



solitary cr somewhat fascicled flowers : calyx-tube long-cylindrical, 

 the limb deciduous ; petals wanting : carpel usually solitary. 



* * * Herbs : carpels few-many : calyx valvate in the bud, with a set 

 of bractlets alternating with the lobes. 



4- Seeds erect from the base of the cell : style terminal, often geni 

 culate in the middle. 



7. Geum. Carpels numerous, on a dry receptacle: the elongated style 

 in fruit mostly geniculate and articulated near the middle or plumose. 



-*- +- Seed suspended or ascending: radicle superior: style small, 

 naked, not geniculate. 



8. Fragaria. Petals broad and conspicuous, sessile: carpels numerous, 

 scattered on a large fleshy, becoming pulpy, receptacle ; style lateral : 

 leaves trifoliolate. 



9. Comarum. Carpels very numerous, on a large fleshy or spongy 

 convex receptacle : style inserted below the apex of the ovary : leaves 

 pinnate: coarse marsh perennials. 



10. Sibbaldia. Petals narrow and minute, sessile: stamens 5; filaments 

 very short, Aliform: carpels 5-10, on a dry receptacle: leaves trifolio- 

 late. 



11. Potentilla. Petals usually conspicuous, sessile : stamens usually 20 

 or more ; filaments narrow or filiform : carpels mostly numerous, on a 

 dry receptacle : leaves pinnate or digitate ; leaflets not confluent. 



12. Horkelia. Petals conspicuous, with claws: stamens 10 or more; fil- 

 aments more or less dilated or subulate: carpels usually many, on a 

 dry nearly naked receptacle : leaves pinnate; leaflets many, the upper 

 ones often confluent. 



13. Ivesia. Petals with claws : stamens 5-20 ; filaments filiform : car- 

 pels 1-15, on a dry villous receptacle: leaves pinnate; leaflets cleft or 

 parted, often small and very numerous, closely imbricated. 



Tribe iv. Rube^e. Calyx open, without bractlets : stamens 

 numerous: carpels several or numerous, on a spongy receptacle, 

 becoming pulpy-coated achenes in fruit : ovules 2, pendulous, 

 but one maturing. 



14. Rubus. Carpels 2-many, crowded on an elevated receptacle, ripen- 

 ing into a coherent body of small drupes. 



Tribe v. Spir^e^e. Calyx campanulate, imbricate or some- 

 times valvate in the bud : carpels few, mostly 5, rarely solitary, 

 becoming follicles or dehiscent 2-valved pods : styles terminal : 

 seeds 1-10 in each carpel, pendulous or ascending. 



§ 1 Carpels becoming 1-seeded achenes. 



15. Holodiscus. Carpels membranaceous, woolly, 1-seeded: shrubs 

 with simple lobed leaves without stipules. 



§ 2 Carpels becoming follicles or 2-valved capsules, usually several- 

 seeded. 



* Seeds in ours not known : carpels distinct : ovules 2, one above 

 the other, pendulous ■ herbs with pinnately divided stipulate leaves. 



16. Filipendula. Carpels membranaceous, 1-celled, distinct: leaves 

 pinnate, the terminal leaflet large and lobed. 



