304: CICHORIACEAE 



9. LACTUGA L. 



Pappus bright white. 

 Leaf-blades spiny-toothed and often spiny along the midrib beneath : corollas 

 yellow. 

 Involucres 6-12-flowered : beak longer than the achene-body. 



I. L. Scariola. 

 Involucres 12-20-flowered : beak shorter than the achene-body. 



i. L. sagittifolia. 

 Leaf-blades without spines on the margins or midrib. 

 Achenes thin, the body prolonged in a slender beak. 

 Leaf-blades, at least some of them, pinnatifid. 



Leaves glabrous. 3. L. Canadensis, 



Leaves hirsute, at least on and about the midrib. 4. L. hirsuta. 

 Leaf-blades entire or merely toothed. ■^. L. sagittifolia. 



Achenes thick, the body beakless or with a mere thick neck. 

 Leaf -blades toothed : achene-body not narrowed into a neck. 



5. L. villosa. 

 Leaf-blades pinnatifid : achene-body narrowed into a neck. 



• 6. L. Floridana. 



Pappus brown. 7. L. spicala . 



1. Lactuca Scariola L. Prickly Lettuce. (Man. p. 898 ; I. F. /. 

 3S37-) 1° fields and waste places. Me. to S. Dak., N. J., Ga., Neb., Colo, 

 and Kans. Nat. from Eu. — Pennsylvania : Northampton ; Lancaster ; 

 Franklin ; Allegheny. 



2. Lactuca sagittifolia Ell. Arrow-leaved Lettuce. (Man. p. 

 898 ; I. F. f. JS4I.) In dry open soil, N. B. and Ont. to Idaho, Ga. and 

 Kans. — Pennsylvania : Northampton ; Lancaster ; Allegheny. 



3. Lactuca Canadensis L. Wild or Tall Lettuce. (Man. p. 81 

 I. F. f. SSS9-) In moist, open places, N. S. to the N. W. Terr., south to 

 Ga., Ala., La. and Ark. — Pennsylvania . Monroe ; Northampton 

 Bucks ; Luzerne ; Lancaster ; York. 



3a. L. Canadensis montana Britton. (Man. p. 898.) — Monroe 

 Bucks ; Allegheny. 



4. Lactuca hirsuta Muhl. Hairy Wood-LETTuce. (Man. p. S98 

 I. F. /. SS40:) la dry soil, Me. to Ont., Minn., Ala. and Te:s:.— Pennsyl- 

 vania : Elk ; York. * 



5. Lactuca villosa Jacq. Hairy-veined Blue Lettuce. (Man. p. 

 899; I. F./. SS4J-) In thickets, N. Y. to 111., south to Fla., Ga. and Ky. 

 — Pennsylvania : Northampton ; Lancaster ; Franklin ; Alle- 

 gheny. 



6. Lactuca Floridana (L.) Gaertn. Florida LETTUCE. (Man. p. 899; 

 I- F- / 3S4-1-) In moist, open places, southern N. Y. and Pa. to 111., 

 Neb., Fla., La. and Kans. — Pennsylvania : Northampton ; Lancaster ; 

 Franklin ;' Delaware. 



7. Lactuca spicata (Lam.) Hitchc. Tall Blue LETTUCE. (Man. 

 p. 899; I. F. /. 3S4S-) In moist soil, Newf. to Mail., south to N. C, 

 Tenn., Iowa and S. Dak. — Pennsylvania: Monroe; Northamp- 

 ton ; Bucks ; Chester ; Lancaster ; Lebanon ; Franklin ; Erie ; 

 Allegheny. 



