DICOTYLEDONS. 241 



stem erect, slender, rough-pubescent, paniculately branched above, 

 '2-3 ft, high; leaves entire or sliglitly serrate, pubescent, the lower 

 oval to oV>long, long-pet ioled, the upper lanceolate to linear, sessile; 

 heads small, in corymbose panicles : bracts smooth ; ray flowers 

 numerous, white or purplish; pappus double, the outer row of short, 

 chaffy scales, the inner of rougli hairs. May-September. Common 

 ill old fields. 



^5. E. VERNUS (L.) T. & G. Early Fleabane. Perennial, 

 from a thick rootstock; stem erect, slender, smooth, scape-like, 1-2 

 ft' high ; leaves mostly basal, spatulate to obovate, thick, entire or 

 slightly toothed, with a margined petiole, upper leaves small and 

 bract-like; heads in small, peduncled corymbs; bracts linear; ray 

 flowers '20-30, white or pink; paj^pus single. March-May, Com- 

 mon on wet ground. 



VIII. SILPHIUM. 



Perennial herbs with resinous juice; stems erect, leafy; 

 leaves alternate, opposite or wliorled ; heads radiate, large, in 

 corymbs or panicles ; involucral bracts leafy, imbricated in 

 several rows, the inner small and chaffy ; receptacle with 

 linear, acute chaff; ray flowers numerous, yellow, pistillate 

 and fertile, disk flowers numerous, perfect but sterile ; style 

 undivided; achenes in 3-4 rows, compressed, orbicular to 

 obovate, winged on the edges, emarginate at the apex; pappus 

 none, or coalesced with the 2 teeth of the achene. 



1. S. LACixiATLM L. Co.Mi'Ass Plant. Stem stout, striate, 

 iough-his])id with white hairs, very resinous, few-leaved, simi)le, 

 4-8 ft. high; leaves mostly Itasal, petioled, oval in outline, deeply 

 pinnately parted, rough-hispid, mostly erect and facing to the east 

 or west, stem leaves alternate, small, nearly entire ; heads spiked 

 or racemed ; bracts large, ovate, the tips spreading; ray flowers 20- 

 ;>0, 2-3 in. wide; achenes round-obovate, emarginate. .lune-Septem- 

 l»er. On ])rairies and open grounds. 



2. S. TEKEiUNTiiiNACErM .Iae(|. Pi; Aii;ii: l)n< K. Stein smooth, 

 branched above, nearly leafless, 3— S It. high; leaves nearly all basal, 

 eordate-fjvate, acute at the apex, coarsely toothed, rough, long- 

 petioled, mostly facing to the east or west; heads loosely pani- 

 eled, 2-3 in. wide; bracts oval, obtuse, sniootii; ray flowers 12-20; 

 acheiu's obovate, 2-to<»tlied at tlie ajiex. June September. In ojvn 

 woods and Helds. 



