500 TRANS. ST. I.OUIS ACAD. SCIENCE. 



++ ++ Stem pubescent, 

 S. Canadensis, L. Spec. 



Open ground, roadsides, moist woods, etc.; common. 



Resembles S. seroiiiia in general appearance, but stem, and usually smaller anil 

 narrower leaves, pubescent. 



Var. PKOCEKA, (Ait.) Torr. & Gray, Fl. ii. p. 224.— /S'. procrra^ 

 Ait. Hort. Kew. 



Open ground ; not uncommon. < 



Plant paler, leaves less serrate, and panicle much smaller than in S. Canadensis . 



S. NEMOKALis, Ait. Hort. Kew. 

 Dry gravelly soil ; abundant. 



Stem (a few inches to z feet high) cinereous-pubescent; leaves spatulate or ob- 

 lanceolate, entire, or the lower sparingly serrate; panicle recurved, or in the taller 

 specimens sometimes erect. 



* * * Heads disposed in corymbiform or cymose clusters. 

 H- Stem densely pubescent. 



8. BiGiDA, L. Spec. 



Prairie; common. 



Stem 2 to 3 feet high, softly pubescent or scabrous; radical leaves on long peti- 

 oles; lower cauline, oblanceolate tapering into slender petioles; upper, ovate to ob- 

 long, sessile ; all entire or nearly so. 



-H- -;- Stem nearly or quite glabrous. 



S. RiDDELLii, Frank, in Riddell, Syuojis. 1835. 



Sloughs, often growing in the water; infrequent. 



I^ow prairie north of Ames, and elsewhere. Stem smooth, : to 2 ft. high; leaves 

 entire, long and narrow, erect from a sheathing base. 



S. GRAMINIFOLIA, (L.) Ell. Sk. ii. — Chrysoeoma c/ram in {folia, L. 

 Spec. — 5. lanceolata^ L. Mant. p. 114. 

 Wet places; abundant. 



Stem much branched, usually smooth, i to 3 feet high, with long and slender 

 rootstocks; leaves narrowly lanceolate, 3-nerved , heads glomerate - sessile. I'low- 

 ering late. 



Boi.TONtA ASTEROIDES, (L.) L'Her. Sert. Augl. 178S. —J/a^ncaHa 

 asteroides, L. Mant. p. 116. 

 Sloughs ; frequent. 



This has the general appearance of an Aster, but the pappns consists of two 

 (under a lens, setose) awns and a ring- of short bristles; the achene is setulose on 

 the upper part of its winged margin. 



Aster OBLOJSGiFoiiius, Nutt., var. rigidulus, Gray, Syn. Fl. i. 2. 



Rocky bluffs ; infrequent. 

 A. Nov.e-Akglt.e, L. Spec. 



Sloughs and moist places; abundant. 

 Var. EOSEUS, (Desf.) DC. Prod, v.— ^. /osrtfs, Desf. Cat. H, Par. 

 3d ed. 



With the above; an infrequent form. 

 A. SERiCEUS, Vent. Hort. Cels. 1800. 

 Dryl)anks; infrequeiit. 



