236 coMPosiT.iL. . (composite family.) 



§ 6. OXYTRIPOLIUM, DC. Scales of the involucre hnhricaied, without herha- 

 rroKS ti/)s, iiaiuilli/ rcry acute, the outer passing into scale-like brads : pappus sojl 

 ami cajtHhn If : aihenla striate. 



39. A. flexu6sus, Nutt. Stem zigzag, rigid, forked (O"- 20' hi|,^h) ; the 

 branches bearing/ lan/e avlitdri/ heads ; leaves linear, thick aiul Jlcshy, j)oiiitcd, entire, 

 seales of the hell-shaped involucre imbricated in many roivs, ovate-hxneeolatc with 

 awl-shaped points; ruifs numerous, lanje, pale purjile. — Salt marshes on the 

 coast, Maine to Viriijinia. Sept. 



40. A. Iinif61ius, L. Annual; stem iiuk-1i In-anchcd (G'-24' higli), the 

 branches bearing numerous racemose or panicled small heads ; leaves linear-lanceolate, 

 pointed, entire, flat, on the branehcs awl-shaped ; seales of the oblong involucre 

 linear-aivl-shnped, in feiv rows ; rays somewhat in two rows, short, not projecting be- 

 yond the disk-, more numerous than the disk-flowers, purplish. (A. subulatus, 

 Michx.) Salt marshes, on the coast, Maine to Virginia. Aug. -Oct. 



41. A. angustus, Torr. & Gr. (Tripolinm angustum, Z/«f//. T. frondo- 

 sum, Nutt. Also in Siberia, Conyza Altiiica, DC, and Brachyactis ciliata, 

 Ledtb.) An annual species related to the last, but with broader leaves, very 

 many minute rays, and more copious pappus : comes from the northwest to near 

 the borders of Wisconsin. 



14. ERIGERON, L. Fleabaxe. 



Heads many-flowered, radiate, mostly flat or hcmisj)herical ; the narrow rays 

 very numerous, pistillate. Scales of the involucre narrow, nearly equal and 

 little imbricated. Keceptaclc flat or convex, naked. Achenia flattened, usually 

 pubescent and 2-ncrved. Tappus a single row of capillary bristles, with minuter 

 ones intermixed, or with a distinct short outer pappus of little bristles or ehaff'y 

 scales. — Herbs, with entire or toothed and generally sessile leaves, and solitary 

 or corymbed heads. Disk yellow ; ray white or purple. (Name from vp? spring, 

 and ytpav, an old man, suggested by the hoary appearance of some of the ver- 

 nal species.) 



§ 1. C^NOTUS, Nutt. Rays inconspicuous, in sevei-al rows, scarcely longer than 

 the pappus: pappus simple: chiefly annuals and bienniids. 



1. E. Canad^nse, L. (House-weed. Butter-weed.) Bristly-hairy; 

 stem erect, wand-like (3° -5° high) ; leaves linear, mostly entire ; those from the 

 root cut-lobed ; /iea(/s very numerous and small, cylindrical, paH/c/<rf. — Waste 

 places; a common weed, now widely ditiPused over the world. July -Oct. — 

 Ligules much shorter than their tube, white. (Nat. in En. &e.) 



2. E. divarieatum, Michx. Dijfuse and decumbent (3' - G' hi<:h) ; leaves 

 linear or awl-shaped ; heads loosely coi-ymbed ; rays purple: otherwise like No. 1. — 

 Illinois, Kentucky, and southward. 



3. E. acre, L. Sparsely hairy or smoothish ; stem erect (10' -20' high) ; 

 leaves lanceolate or the lower spatulatc-oblong, entire ; heads several or rather 

 numerous, racemose or at length corymbose, nearly hemisidicrical (4'' -5" 

 long) ; rays purplish or bluish, equalling or a little exceeding the copious pap- 

 pus. — Shores of Lake Superior (Dr. Robbins, Prof. Porter, &.C.), and northwest- 

 ward. (Eu.) 



