VOL. II.] 



CROWFOOT FAMILY. 



i. Pulsatilla hirsutissima (Pursh) Brit- 

 ton. American or Nuttall's Pasque 

 Flower. (Fig. 1581.) 



Clematis hirsutissima Pursh, Fl. Am. Sept. 385. 



1814. 



Anemone Nuttalliana DC. Syst. i: 193. 1818. 

 Anemone patens var. Nuttalliana A. Gray, Man. Ed. 



5, 36- 1867. 

 Ptdsatilla Inrsutissima Britton, Ann. N. Y. Acad. 



Sci. 6: 217. 1891. 



Villous, 6 / -i6 / high. Leaves much divided into 

 narrow linear acute lobes, the basal on slender 

 petioles, those of the involucre sessile and erect 

 or ascending; sepals ovate-oblong, light bluish- 

 purple; fruit a head of silky achenes with long 

 plumose styles, like those of some Clematis. 



In dry soil, prairies of Illinois to the Northwest 

 Territory, British Columbia, Nebraska and Texas. 

 After flowering the peduncle elongates, sometimes 

 to a foot or more. March-April. 



18. CLEMATIS L. Sp. PI. 543. 1753. 



Climbing vines, or erect or ascending perennial herbs, more or less woody. Leaves op- 

 posite, slender-petioled, pinnately compound, lobed, or in some species entire. Sepals 4 or 

 5, valvate in the bud, petaloid. Petals none. Stamens oo. Pistils oo. Achenes i-seeded. 

 Style long, persistent, plumose, silky or naked. [Greek name for some climbing plant.] 



About loo species of very wide geographic distribution, most abundant in temperate regions. 

 Besides the following, some 12 others occur in the southern and western parts of North America. 



Jf Climbing vines ; leaves pinnate or 3-foliolate. 

 Flowers panicled, numerous ; filaments glabrous. 

 Leaves 3-foliolate; eastern. 

 Leaves pinnately 5~7-foliolate; western. 

 Flowers solitary; filaments pubescent. 



Sepals thin; fruiting styles silky, not plumose. 



Sepals conspicuously dilated; leaves thin, pinnately veined. 

 Sepals with recurved tips; venation strongly reticulated. 

 Sepals leathery, their tips recurved; fruiting styles plumose. 



1. C. Virginia na. 



2. C. ligusticifolia. 



3. C. crispa. 



4. C. Sinixii. 



5. C. Viorna. 



-Jf -5f Erect or ascending perennial herbs ; leaves simple or pinnate. 



Glabrous, glaucous; leaves simple, or pinnate and tendril-bearing. 6. C. Addisonii. 



Villous-pubescent: leaves simple or pinnate, not tendril-bearing. 

 Leaves simple, entire or rarely lobed. 



Fruiting styles long, plumose; eastern species. 



Flowers yellowish-green; style-plumes brown; achenes straight. 7. C. ochroleuca. 

 Flowers purple ; style-plumes white; achenes distinctly oblique. 8. C. ovaia. 

 Fruiting styles short, silky; western species. 9. C. Fremontii. 



Leaves pinnate, or the lowest entire. 10. C. Scottii. 



i. Clematis Virginiana L,. Virginia 

 Virgin's Bovver. (Fig. 1582.) 



Clematis I 'irgiiiiana L. Amoen. Acad. 4: 275. 1759. 

 A long vine, climbing over bushes in low 

 woodlands and along fences and water-courses. 

 Leaves glabrous or nearly so, trifoliolate; leaf- 

 lets mostly broadly ovate, acute at the apex, 

 toothed or lobed, sometimes slightly cordate; 

 flowers white, in leafy panicles, polygamo-dioe- 

 cious, &"-i$" broad when expanded; filaments 

 glabrous; persistent styles plumose, \ f long or 

 more. 



Georgia to Kansas, northward to Nova Scotia 

 and Manitoba. Leaves rarely 5-foliolate. Ascends 

 to 2600 ft. in Virginia. July-Sept. 



Clematis Virginiaaa Catesbyana (Pursh) Britton. 

 Clematis Catesbyana Pursh, Fl. Am. Sept. 736. 1814. 



Leaves more or less pubescent, often biternate. 

 South Carolina and Florida to Missouri and Mis- 

 sissippi. 



