434 COMPOSITiE. Prenanthes. 



* * * Heads 5-18-flowered, sometimes racemose, usually paniculate, commonlj'' pendulous: 

 leaves diverse, but the cauline nearly all petioled; lower and radical or some of them cordate, or 

 hastate, or truncate at base: root mostly fusiform-tliickeued or tuberous, as in the preceding: 

 akenes obscurely or minutely striate and sometimes 3-4-costate or angled. 



.(^ Involucre cylindraceous, distinctly calyculate with very short and ovate to triangular-subulate 

 appressed scale-like bracts: principal bracts with their covered margins wliite-scarious in dried 

 specimens. Species variously called Wjiite Lettuce, Lion's-foot, Kattlesnake-root, 

 Gall-of-the-eakth. 



++ Pappus cinnamon-brown: stem tall, generally purplish. 



P. alba L. Glabrous, often glaucesceut, 2 to 5 feet high, rather stout : leaves sometimes all 

 deltoid-hastate and nearly dentate, on slender winged petioles, or uppermost oblong with 

 tapering base, or most of them 3-5-lobed or parted : inflorescence thyrsoid-pauiculate : invo- 

 lucre 8-12- (rarely 5-) flowered, commonly purplish-tiuged : flowers dull white: pappus 

 reddish-brow^n. — L. as to Hort. Cliff. & Syn. Pluk., not of herb.; Michx. Fl. ii. 83, in part 

 {not of herb, proper) : Sims, Bot. Mag. 1. 1079 ; Pursh, Fl. ii. 499 ; Bigel. Fl. Bost. ed. 2, 286. 

 P. ruhicunda, Willd. Spec. iii. 2537, excl. syn. ; Pursh, 1. c. P. suavis, Salisb. Parad. Lond. 

 t. 85. P. Miamensis, ovata, Si, proteoph ijlla , Riddell, Syn. W. PL, to be divided between this 

 and following species. Harpahjce alba, Dou ex Steud. ; Beck, 1. c. N^ahulus trifoliolutus, 

 Cass. Diet, xxxiv. 95. N. suavis, DC. 1. c. 241. N. albus. Hook. Fl. ii. 294, chiefly; Torr. 

 & Gray, Fl. ii. 480, excl. var. — Open oak-woods and sandy or gravelly ground, Canada and 

 New England to Saskatchewan, Illinois, and the upper country of Georgia, &c. 



++ +-!- Pappus sordid straw-color or whitish: leaves diversely variable, assuming all the forms 

 of the preceding species. 



P. serpentaria, Pursh. Commonly 2 feet high, glabrous or a little hirsute-pubescent : 

 stem sometimes purple-spotted, rather stout : inflorescence corymbosely thyrsoid-pauiculate ; 

 the heads mostly glomerate at summit of ascending or spreading flowering-branches or pe- 

 duncles : involucre green, rarely purplish-tinged, 8-1 2-flowered : flowers purplish, greenish 

 white, or ochroleucous. — Fl. ii. 499, t. 24; Ell. Sk. ii. 261. P. alba, L. Spec, as to PI. 

 Gronov. ; Walt. Car. 193; Ell. Sk. ii. 259. Harpalyce serpentaria, Don, 1. c.; Beck, 1. c. 

 Nabal.us trilobatus, Cass. Diet. 1. c. ? N. serpentarius (Hook. 1. c), N. trilobatus, & N. 

 Fruseri, DC. 1. c. (N. glaucus, Prenanthes glauca, Ilaf. Fl. Lud. 57, & Esojion (/lauciiin, Raf. 

 1. c. 149, has no foundation.) — Open grounds, commonly in sandy or sterile soil, New Bruns- 

 wick aud Canada to Florida. 



Var. nana. Stem more simple and strict, 6 to 16 inches high, smooth aud glabrous : 

 inflorescence contracted ; often sessile or subsessile clusters of heads in the axils of most of 

 the cauline leaves: involucre livid-greenish. — P. alba, var. nana, Bigel. Fl. Bost. 1. c. 

 Nabalus nanus (also N. serpentarius, var. l<evis), DC. 1. c. ; Torr. & Gray, 1. c. A form with 

 leaves pedately parted into narrow divisions is probably A^. trifoliolutus, Cass. — Mountains 

 of N. New England to Canada, S. Labrador, and Newfoundland. 



Var. barbata. Sometimes hirsutulous-pubescent : leaves from oblong to deltoid- 

 hastate, from denticulate to sinuate-lobed, upper not rarely sessile : involucre sometimes 

 sparingly and sometimes copiously beset with bristles. — P. crepidinea. Ell. Sk. ii. 259, not 

 Michx. Nabalus integrifolius (Cass. 1. c. 96, with " subsagittate " leaves), & N. Fraseri in part, 

 DC. L c. N. Fraseri, var. integrifolius & var. barbattis, Torr. & Gray, Fl. ii. 481. N. (& 

 Prenanthes) Roanensis, Chickering in Bot. Gazette, v. 155, vi. 191, a mountain form, a span 

 to a foot high, with most of the leaves hastate-deltoid, aud bristles on the involucre copious 

 and conspicuous. — Mountains of N. and S. Carolina to Alabama; apparently first coll. by 

 Fraser, then by Macbride; the high mountain form by Chickering on Roan Mountain. Oc- 

 casionally a few of these setose hairs are found on the involucre of ordinary P. serpentaria, 

 and iu this variety some heads are almost destitute of them. 



P. altissima, L. Commonly 3 to 7 feet high, slender, not glaucous, glabrous or nearly so 

 (in open ground sometimes purple-stemmed and hispidulous !) : leaves thin, disposed to be 

 hastate, deltoid, or cordate, sometimes ovate, aud denticulate or dentate ; lower not rarely from 

 3-lobed to pedately 5-parted : panicle elongated and loose, very commonly subsessile clusters 

 in the axils of many cauline leaves: involucre^ narrow-cylindrical, greenish, always glabrous, 

 5-6-flowered : flowers greeuish-ochrolcucous. — Spec. ii. 797, from char., .syn. Pluk. (Aim. 

 t. 317) & Vaill., aud perhaps herb. (P. alba, L. herb., specimen from Kalni, is either this or 



