Thistle Family. 83 



Fayette county. (Doelllnncria nmbellala, (Mill.) Noes.) The variety i-ubens 

 Gray has the lower surfaces of the leaves pubescent and is reported from 

 Story county. (D. umbellata pubens (Gray) Uritton). 



ERIGERON L. Flkabajje. Herbs, with alternate simple leaves, and soli- 

 tary or corymbose pedunculate heads. Ray-flowers many, pistillate, white or 

 purple; disk-flowers yellow. Involucral scales narrow, equal, scarcely im- 

 bricated. Receptacle flat or convex. Pappus of capillary bristles, mostly 

 simple. Achenes compressed, 2-nerved, frequently pubescent. 



* Hewls small, rays short, inconspicuous, in several rows. 



E. canadensis L. Horse-weed. Stem 1-5 feet high, erect, hairy; leaves 

 linear to linear-lanceolate, usually entire, radical cut-lobed; heads small, 

 numerous, paniculate; rays short, white. Waste places; July-October; com- 

 mon. (LeptUon cawidense ( L. ) Dritton). 



E. ditfaricatus Mx. Stems low, 3-15 inches high, diffuse and decumbent, 

 hairy; leaveslinear, entire; heads small, corymbose; rays purple. Prairie or o- 

 pen woods; June-August; common; Emmet, Story, Johnson. Muscatine, Appa- 

 noose, Decatur, Ringgold, aDd Fremont counties. {L. dimvricaturn (Mx. ) Raf.) 

 * * Heads turner, rays elongated, conspicuous, in one or more rows. 



E. annuus (L.) Pers. Daisy Fleabane. Stem 2-4 feet high, branching, 

 hirsute; leaves ovate to lanceolate, sessile or lower on margined petioles, 

 coarsely and sharply toothed; rays numerous, purplish. Fields and waste 

 places; June-August: common. 



E. strigosus Muhl. Daisy Flenhane. Stem 2-3 feet high, branched, ap- 

 pressed pubescent or nearly smooth; upper leaves lanceolate, lower oblong 

 or spatulave, 3-nerved, tapering into a petiole, all mostly entire; rays white. 

 Fields; June-August; common. (E. ramus us (Walt.) B. S. P.) 



E. philadelphicus h. Common Fleabane. Stem about 2 feet high, hairy; 

 leaves clasping by a heart-shaped base, ovate, or lower spatulate, entire or 

 remotely toothed, thin; heads few, corymbed; rays rose-purple. Upland 

 woods; May-July; common. 



E. bellidifolius Muhl. Roliin's Plantain. Stem 1-2 feet high, hairy, sim- 

 ple; radical leaves obovate or spatulate, sparingly toothed, stem leaves re- 

 mote, lance-oblong, clasping, entire: heads few, large, on slender peduncles; 

 rays 50 or more, linear-spatulate, rather broad, purple. Woods; May-June; 

 infrequent. Winneshiek. Fayette, Muscatine, Delaware, Johnson, Henry 

 and Jackson counties. (E. palchellus Mx.) 



ANTENNARIA Gaertn. Perennial white-woolly herbs, with alternate en- 

 tire leaves, and corymbed heads of dioecious or polygamo-dioecious flowers. 

 Heads many-flowered, discoid. Scales of the involucre imbricated, white or 

 colored, dry and scarious. Receptacle sub-convex, foveolate, not chaffy. 

 Pappus a single row of bristles, in the pistillate flowers capillary and united 

 at the base, in the staminate flowers thickened and barbellate above. Fertile 

 corollas slender. Achenes terete or flattish. 



A. plantaginifolia (L.) Richards. Stem 4-18 inches high, simple, with 

 running stolons, forming patches, radical leaves spatulate to obovate or oval, 

 3-nerved, petioled, cauline leaves sessile, oblong or lanceolate to linear, the 

 upper small, bract-like; heads in a close terminal corymb. Fields and upland 

 woods; April-May; common. 



ANAPHALIS DG. White-woolly perennials, with many of the characters 

 of the preceding genus. Fowers dioecious, usually the pistillate heads with a 

 few perfect but sterile flowers in the center. Pappus in the pistillate flowers 



