88 RANUNCULACEAE 



Achenes not villous. 



Achenes wing-margined; plant stout. 



Sepals yellow; styles very long, reflexed. 10. A. Richardsoni. 



Sepals white or pink; styles not reflexed. 



Flowers cyniose; achenes sparsely hirsute when young, sessile; styles long, 



straight. 11. A. canadensis. 



Flowers subiHnbellate ; achenes glabrous, stipitate; styles short, curved. 



12. A. zephyra. 

 Achenes not wing-margined, pilose; style minute; plant slender; flowers solitary. 



13. A. Piperi. 



2. PULSATILLA Adans. Pasque-flower, Blue Tulip, Wild Crocus, 

 Lion's Beard (Fruit). 



Flowers purple or violet, seldom white; involucral leaves sessile, palmately divided into 

 linear lobes. 1. P- ludoviciana. 



Flowers white or tinged with purple; involucral leaves petioled, ternate and twice pin- 

 nately dissected. 2. P. occidentalis. 



3. THALICTRUM L. Meadow Rue, Maid-of-the-Mist. 



Flowers perfect. 



Plant 2 dm. or less (rarely 3 dm.) high; achenes turgid; filaments filiform. 



1. T. alpinum. 

 Plant 3-10 dm. high; achenes flat and very oblique; filaments clavate. 



2. T. sparsiflorum. 

 Flowers dioecious or polj'gamous. 



Achenes turgid, thick- walled ; ribs thick and almost corky, separated by acute grooves. 

 Plants polygamous; stem-leaves subsessile, the basal ones petioled. 



Achenes, petiolules, and lower surfaces of the leaves decidedly viscid-pubes- 

 cent. 3. T. dasycarpum. 

 Achenes. petiolules, and the lower surfaces of the leaves glabrous or slightly 

 viscid-puberulent. 4. T. purpurascens. 

 Plants dioecious ; all leaves petioled. 



Achenes equally acutish at both ends; leaves very thin and not strongly veined. 



5. T. dioicum. 

 Achenes more acute at the upper end than at the lower; leaves firm, strongly 

 veined. 6. T. venulosum. 



Achenes more or less flattened, thin-walled; ribs not thick, separated by wide, 

 shallow, rounded grooves. 

 Achenes sessile. 



Achenes more than twice as long as broad, slightly if at all obUque. 



Achenes about 4 times as long as broad, 6-8 mm. long, 1.5-2 ram. wide. 



7. T. occidentalc. 

 Achenes less than 3 times as long as broad. 



Achenes 6-8 mm. long, 2.5-3.5 mm. ^vide. 8. T. megacarpiun. 



Achenes 4-5 mm. long, 1.5-2 mm. wide. 9. T. columbianum. 



Achenes not quite twice as long as broad, decidedly oblique. 



10. T. Fendleri. 

 Achenes stipitate. 11. T. slipitatum. 



4. TRAUTVETTERIA F. & M. False Bugb.^ne. 



styles in fruit about one-tliird as long as the body of the achenes; filaments broader than 

 the anthers. 1. T. grandis. 



Styles in fruit less than one-fourth as long as the body of the achenes; filaments not 

 broader than the anthers. 2. T. media. 



5. CLEMATIS L. Virgin's Bower, White Clematis, Traveler's Joy, 



PlPE-.SrE.M. 



Plant dioecious; flowers white, paniculate. 



Inflorescence usually longer than the leaves, its branches and the pedicels strongly 

 ascending; leaflets lanceolate or ovate-lanceolate; sepals oblanceolate. 



1. C. Ugusticifolia. 

 Inflorescence shorter than the leaves, its branches and the pedicels more spreading; 



leaflets broadly ovate, usually subcordate at the base; sepals spatulate. 



2. C. brerifolia. 

 Plant with perfect yellowish flowers, solitary in the axils. 3. C. orientalis. 



6. VIORNA Reichenb. Vase-vixe, Le.\ther-flower, Old Man's Whiskers 



AND Lion's Beard (fruit). 



Sepals not or indistinctly dilated above. 



Calyx rounded-urceolate; sepals broadly ovate, merely the tips spreading. 



Leaf-segments ovate to ovate-lanceolate, 2-5 cm. long. 1. V. Scotlii. 



Leaf-segments linear to lanceolate, 1-2 cm. long. 2. V. Bakcri. 



Calyx elongated-campanulate; sepals oblong-lanceolate, about one-fourth or more 

 of their length spreading. 

 Middle and upper leaves subsessile, thrice ternate; ultimate segments linear or 

 linear-lanceolate. 3. V. hirsutissima. 



Middle and upper leaves distinctly petioled, twice ternate; ultimate segments 

 lanceolate. 4. V. Wycthii. 



