GENUS 17. 



CHICORY FAMILY 



9. Lactuca villosa Jacq. Hairy-veined 

 Blue Lettuce. Fig. 4076. 



L. villosa Jacq. Hort. Schoen. 3: 62. pi. 367. 1798. 

 Sonchus acuminatus Willd. Sp. PI. 3: 1521. 1804. 

 Mulgedium acuminatum DC. Prodr. 7: 249. 1838. 

 L. acuminata A. Gray, Proc. Am. Acad. 19 : 73. 1883. 



Annual or biennial ; stem glabrous, leafy up to 

 the paniculate inflorescence, 2-6 high. Leaves 

 oblong, ovate or lanceolate, acuminate, acutely den- 

 tate or the teeth mucronate-tipped, glabrous above, 

 pubescent with short stiff hairs on the veins be- 

 neath, sessile and slightly clasping at the base, or 

 petioled, 4'-6' long, i'-2j' wide, the lowest some- 

 times lobed at the base; heads numerous, 3" -5" 

 broad; peduncles usually minutely scaly; rays 

 blue ; involucre about 5" high, its outer bracts 

 much shorter than the inner, some or all of them 

 obtuse ; achenes thick, oblong, little flattened, nar- 

 rowed above ; pappus white. 



In thickets, New York to Illinois, Nebraska, south 

 to Florida, Georgia and Kentucky. July-Sept. False 

 lettuce. 



10. Lactuca floridana (L.) Gaertn. False or 

 Florida Lettuce. Fig. 4077. 



Sonchus floridanus L. Sp. PI. 794. 1753. 



Lactuca floridana Gaertn. Fruct. & Sem. 2: 362. 1791. 



Mulgedium floridanum DC. Prodr. 7: 349. 1791. 



Annual or biennial ; stem glabrous, rather stout, 

 leafy up to the large, paniculate inflorescence, 3-7 

 high. Leaves deeply lyrate-pinnatifid, or sometimes 

 cordate-ovate, sessile or petioled, ^'-12' long, glabrous 

 above, pubescent on the veins beneath, the terminal 

 segment usually broad, triangular, acute or acumi- 

 nate, the lateral ones lanceolate to oval, acute, all 

 usually dentate, or the leaves irregularly lobed; 

 heads numerous, 3"-S" broad ; peduncles commonly 

 scaly ; rays blue ; involucre about 6" high, its outer 

 bracts much smaller than the inner ; achenes thick, 

 somewhat compressed, narrowed above into a short 

 beak; pappus white. 



In moist, open places, southern New York and Penn- 

 sylvania to Illinois, Kansas, Florida and Texas. Porto 

 Rico. July-Sept. 



ii. Lactuca spicata (Lam.) Hitchc. 

 Tall Blue Lettuce. Fig. 4078. 



Sonchus spicatus Lam. Encycl. 3: 401. 1789. 

 Mulgedium leucophaeum DC. Prodr. 7 : 250. 1838. 

 Lactuca leucophaea var. integrifolia A. Gray, 



Syn. Fl. i : Part 2, 444. 1884. 

 Lactuca spicata integrifolia Britton, Mem. Torr. 



Club 5 : 350. 1894. 

 L. spicata Hitchc. ; Britt. & Brown, 111. Fl. 3 : 276. 



1898. 



Annual or biennial ; stem usually stout, gla- 

 brous, 3-i2 high, leafy up to the large, 

 rather dense panicle. Leaves deeply pinnatifid 

 or lobed to entire, sharply dentate with mu- 

 cronate-pointed teeth, sessile, or the lower 

 narrowed into margined petioles, glabrous on 

 both sides, or pubescent on the veins beneath, 

 5'-i2' long, 2'-6' wide; heads very numerous, j 

 about 2" broad ; peduncles minutely scaly ; *" 

 rays blue to white ; achenes oblong, com- 

 pressed, narrowed above into a short neck; 

 pappus brown. 



In moist soil, Newfoundland to Manitoba, 

 North Carolina, Tennessee, Iowa, South Dakota 

 and Colorado. Ascends to 2000 ft. in North 

 Carolina. Races differ in leaf-form and in color 

 of the flowers. Milk-weed. July-Oct. 



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