CARDUACEAE 1189 



4-6 mm. high ; bracts oblong-lanceolate to linear-lanceolate, obtuse or acutish : ray-flowers 

 with ligules 4-6 mm. long : achenes 3-4 mm. long. 



In low sandy soil, South Carolina to Florida and Mississippi. Fall. 



37. EUTHAMIA Nutt. 



Perennial caulescent herbs, with elongated rootstocks. Leaves alternate : blades nar- 

 row, entire or nearly so. Heads very numerous, radiate, in broad corymbs. Involucres 

 narrow, several-flowered : bracts narrow, often obtuse, glutinous, closely imbricated. 

 Eeceptacle pubescent or fimbrillate. Ray-flowers pistillate, usually more numerous than 

 those of the disk, with inconspicuous ligules. Corollas yellow. Stigmas with lanceolate 

 appendages. Achenes broadened upward, pubescent. Pappus of long equal bristles. The 

 plants bloom in summer and fall. 



Leaf-blades manifestly 3-5-ribbed : ray-flowers 12-30. 1. E. graminifolia. 

 Leaf-blades 1-ribbed : ray-flowers 5-10. 



Leaf-blades mostly over 3 mm. broad : disk-flowers 3-4. 2. E. leptocephala. 



Leaf-blades mostly less than 3 mm. broad : disk-flowers 5-6. 3. E. Caroliniana. 



1. Euthamia graminifolia (L. ) Nutt. Stem 3-14 dm. tall, corymbose above, finely 

 pubescent or glabrate below : leaf-blades linear, over 4 mm. wide, 3-5-ribbed, finely pubes- 

 cent, at least along the ribs or margins : heads numerous : involucres campanulate, mostly 

 4-4.5 mm. high : ray-flowers 12-30. [Solidago lanceolata L. ] 



In rich soil or thickets, Nova Scotia to the Northwest Territory, Florida and Kansas. 



2. Euthamia leptocephala (T. & G.) Greene. Stems 4-11 dm. tall, glabrous or 

 merely puberulent near the corymbose top : leaf-blades linear, mostly over 3 mm. wide, 

 1-ribbed, glabrous except the scabrous margins : heads rather numerous : involucres tur- 

 binate, mostly 5.5-6 mm. high : ray -flowers 6-10. 



In moist soil, Missouri to Mississippi and Texas. 



3. Euthamia Caroliniana (L. ) Greene. Stems 2-8 dm. tall, glabrous or sometimes 

 sparingly and minutely pubescent, more or less copiously corymbose above : leaf -blades 

 narrowly linear to linear-filiform, mostly less than 3 mm. wide, 1-ribbed, essentially gla- 

 brous, except the margins : heads numerous, sometimes extremely so : involucres cylindric 

 to turbinate-cylindric, 4.5-6 mm. high : ray-flowers 5-8. [Solidago tenuifolia Pursh. ] 



In sandy soil, Massachusetts, Florida and Texas, and locally in the interior. 



38. SOLIDAGO L. 



Perennial caulescent herbs, sometimes shrubby near the base, with the stems usually 

 simple below the inflorescence. Leaves alternate : blades simple, often toothed. Heads 

 radiate, relatively small, paniculate or thyrsoid. Involucres several-flowered, campanulate, 

 turbinate or cylindric : bracts in several series, ribless, the inner successively longer, the 

 outer sometimes extending well down the peduncle. Receptacle small, usually alveolate. 

 Ray -flowers pistillate, in 1 series : ligules yellow or rarely white. Disk-flowers mostly all 

 perfect. Corollas usually yellow, tubular to narrowly campanulate, 5-lobed. Anthers ob- 

 tuse and entire at the base. Stigmas flattened, the appendages lanceolate. Achenes terete 

 or angled, generally ribbed. Pappus of several or many rough capillary bristles in 1 or 2 

 nearly equal series. GOLDENROD. 



A. Heads in axillary short or raceme-like clusters subtended by leaf-like bracts, if aggregated at the 



end of the stem or its branches forming a conspicuously leafy-bracted thyrsus, 

 a. Involucre 2.5-6 mm. high. 



Achenes copiously pubescent : bracts of the involucre'obtuse. 

 Stems and branches terete. 



Leaf-blades mostly less than 2 cm. wide : involucres 3.5-4 mm. high, 1.5-2 mm. thick. 



Leaf-blades mostly over 2.5 cm. wide : involucres 4-5 mm. high, 2.5-3 



mm. thick. 2. 5. asterifolia. 



Stems and branches angled. 



Leaf-blades less than twice as long as broad. 3. S. flexicaulis. 



Leaf-blades over twice as long as broad. 

 Stem glabrous. 



Leaf-blades 2.5-4 times as long as broad. 4. S. flaccidifolia. 



Leaf- blades 5-8 times as long as broad. 



Involucre narrowly campanulate, 4.5-5 mm. high, about 2 



mm. thick ; inner bracts linear. 5. S. Curtisii. 



Involucres broadly campanulate, 5-6 mm. high, about 3 mm. 



thick ; inner bracts oblong. 6. S. lancifolia. 



Stem manifestly pubescent. 7. s pubens 



Achenes glabrous : bracts of the involucre acute. 



