Lactuca. COMPOSITiE. 419 



Stem 2-8 feet high (in var. 3. smaller), simple, stout, hollow. Leaves extremely variable ; 

 in vars. 1. and 3. usually with 2-3 runcinate more or less toothed lobes on each side. Heads 

 rather smaller than in the garden Lettuce. Flowers in var. 2. light yellow or cream-color, 

 often tinged with purple or blue ; in var. 3. yellow varying to purple, or dark red. 



Woods, fields and bushy places ; the first variety very common, particularly in grounds 

 newly burnt over ; the other forms in the vicinity of New-York, rare. July - August. — 

 According to M. Aubergicr, this species does not yield the narcotic substance called lactuca- 

 rivm, found in the Garden Lettuce. The milky juice is insipid and sweetish. 



53. MULGEDIUM. Cass.; DC. prodr.7. p. 2'k7. MULQEDIUM. 



Agathyrsus, D. Don. 

 [ From the Latin, mulgeo, to milk ; on account of its yielding a white juice when wounded.] 



Heads many- flowered. Involucre imbricated ; the exterior scales much shorter than the 

 interior. Receptacle naked, foveolate. Achenia smooth, compressed ; the summit con- 

 tracted into a more or less evident continuous beak, the apex of which is expanded into a 

 flattish ciliolate disk. Pappus of copious roughish bristles. — Caulescent herbs, with pin- 

 natifid or undivided leaves, and paniculate or racemose heads. Flowers blue, rarely dull 

 bluish white or cream-colored. 



^ 1. EuMCLGEDiuM, DC. Pappus bright white : corolla Hue or purple. 



1. MuLGEDiuM ACUMINATUM, DC. Skarp-koved Mulgediutti. 



Smooth ; stem-leaves ovate, acuminate, denticulate or toothed, slightly hairy on the midrib 

 and veins underneath, contracted at the base into a winged petiole , the radical ones sometimes 

 slightly runcinate ; heads in a loose divaricate panicle , the peduncles somewhat scaly ; in- 

 volucre smooth, calyculate-imbricated ; achenia slightly beaked. — DC. prodr. 7. p. 250 ; 

 Torr. <^ Gr. fl. N. Am. 2. p. 498. Sonchus acuminatus, Willd. sp. 3. p. 1521 ; Pursh, 

 fl. 2. p. 502 ; Ell. sk. 2. p. 255 ; Torr. compend. p. 279 ; Darlingt. fl. Cest. p. 446. S. 

 Floridanus, Michx. fl. 2. p. 85 (partly). Lactuca villosa, " Jacq. hort. Schanb. 3. t. 367 ;" 

 Beck, hot. p. 170. 



Biennial. Stem 3-6 feet high, slender, loosely paniculate at the summit. Leaves 4-8 

 inches long and 1-3 inches wide, thin , the lowest sometimes deltoid or triangular-hastate, 

 sinuate-denticulate, smooth above, more or less hairy on the veins underneath ; the winged 

 petiole 1-3 inches long. Heads rather few ; the widely spreading slender peduncles fur- 

 nished with scattered minute scales. Involucre ventricose below. Flowers blue. Achenia 

 much compressed, strongly marked with several ribs on each side, and minutely rugulous 

 transversely ; the slight beak ending in a small whitish disk which supports the pappus. 



Thickets and borders of woods, in moist rocky places ; near New- York. August - Sep- 

 tember. 



53» 



