CHICORY FAMILY 1035 



DC. Meadows and hills: N.M. — Colo. — Utah — Ariz.; Mex. Suhinont. — Mont. 

 My-Au. 



4. L. dumetorum (Greene) Rydb. Leaves 1-2 dm. long, oblanceolate , 

 mostly erect, sinuately toothed or lobed, glabrous or slightly hairy on the veins; 

 teeth or lobes usually triangular; scape 1-4 dm. high; involucres 2-3 cm. high; 

 inner bracts narrowly linear-lanceolate, dilated and bifid at the apex; achenes 

 olive-green; ribs spinulose at the summit, muricate below. T. dumetorum Greene. 

 Mountain valleys: Man. — N.M. — Utah — B.C. Suhmont.—Mont. My-Au. 



5. L. leiospermum Rydb. Leaves spreading, broadly oblanceolate, less 

 than 1 dm. long, dark green, obtuse or acutish, retrorse-dentate, rarely lobed; 

 scape about 1 dm. high, slightly villous when young; outer bracts 7-10 mm. long, 

 lanceolate, %\dth spreading tips, the inner linear, about t\Adce as long, neither 

 corniculate; achenes greenish. T. leiospermum Rydb. Mountains: Colo. Suh- 

 mont. — MoJit. Jl-Au. 



6. L. eriophorum Rydb. Leaves 2-3 cm. long, oblanceolate to spatulate, 

 slightly sinuately dentate or entire; scape 2-3 dm. high; involucres about 1.5 cm. 

 high, somewhat livid; calyculate bracts in a single series, ovate, erect, slightly 

 corniculate. T. eriophorum Rydb. Hills: Mont. Submont. 



7. L. monticola Rydb. Leaves oblanceolate in outline, 6-12 cm. long, 

 from dentate to sinuately lobed with triangular entire lobes, glabrous or nearly 

 so; scape 1-2 dm. liigh*; involucres campanulate, 15-18 mm. high; bracts proper 

 linear-lanceolate, in 2 series, the inner ones with broad scarious margins; achenes 

 greenish or brown; ribs strongly spinulose above. T. montanum Nutt., not DC. 

 Mountains: Alta. — Colo. Submont. — Mont. Je-Au. 



8. L. angustifolium (Greene) Rydb. Leaves oblong-linear, 4^10 cm. long, 

 obtuse or mucronate, denticulate or dentate; scape decumbent, at last twice as 

 long as the leaves; involucre narrowly campanulate; achenes brown, spinulose 

 at the apex, smooth below the middle. T. angustifolium Greene. (?) T. fas- 

 ciculatum A. Nels. Meadows: Wyo. — Colo. Mont. — Alp. Jl-Au. 



9. L, ammophilum (A. Nels.) Rydb. Leaves decumbent, 1 dm. long or 

 less, glabrous, oblong or oblanceolate, sinuate-dentate; scape decumbent, about 

 a,s long as the leaves; involucres about 15 mm. high; bracts proper narrowly 

 linear-lanceolate, slightly scarious-margined ; achenes dark red; ribs spinulose 

 above, tuberculate below. T. ammophilum A. Nels. Grassy valleys: Wyo. — 

 Colo. Mont. — Subalp. Je-Au. 



10. L. rupestre (Greene) Rydb. Leaves narrowly oblanceolate in outline, 

 acute, runcinate-pinnatifid or runcinate-toothed, 3-8 cm. long; involucres nar- 

 rowly campanulate, dark livid green, 10-12 mm. high; proper bracts 10-15, in 2 

 series, lance-linear, the inner series with broad scarious margins; ribs of the 

 achenes spinulose at the summit, muricate below. T. rupestre Greene. (?) T. 

 ovinum Greene. High mountains: Alta. — Mont. — B.C. Subalp. — Alp. Jl-Au. 



11. L. scopulorum (A. Gray) Rydb. Leaves 2-6 cm. long, sinuate-pinnat- 

 ifid; scape 1-6 cm. high; involucres 6-8 mm. high, 5 mm. wide, dark livid green; 

 bracts proper 8-12, in 2 series, oblong-linear, scarious-margined, often obtuse. 

 T. officinale scopulorum A. Gray. T. scopulorum Rydb. Alpine regions: Colo. 

 — Ida. Mont. — Alp. Jl-Au. 



25. LACTUCA (Tourn.) L. Lettuce. 



Tall leafy-stemmed herbs, with paniculate heads. Involucres cylindric, or 

 in fruit conic; bracts imbricate, in 3 or more series. Achenes obcompressed , 

 1-5-nerved on the faces, contracted into a beak dilated at the apex. Pappus of 

 nimierous capillary bristles, which fall off separately. 



Achenes with a slender beak; pappus white. 



Outer bracts (calyculum) not more than half as long as the bracts proper; flowers 

 yellow, rarely tinged with blue. 

 Heads 6— 15-flowered; achenes several-nerved, not rugose; leaves spinulose on the 

 ribs. 

 Leaves sinuate-dentate; achenes dark. 1. L. virosa. 



Leaves sinuately pinnatiQd; achenes light colored. 2. L. Scariola. 



