CICHORIACEAE | 1497 
ong: pappus ee e )— Roadsides, cult. AP and 
vase pace S Fla. Nat. of Trop. Am.—(W. I. Mex , €. A, S. A.)—Al 
year 
14. LACTUCA L. Annual, biennial, or perennial herbs, the stems 
Pi Leaf "blades dc paa broad, entire, toothed, or pinnatifid, some- 
spiny-m erect. Involueres cylindric to ovoid. chene 
Farbe: erc nyo 75 species, in the Northern Hemisphere.— 
Sum.—fall.—-LETTUCES. WOOD-LETTUCES. WILD-LETTUCES. 
Leaf-blades spiny-toothed and often spiny along the midrib beneath: corollas yellow. 
Involucres 6-12-flowered. 
Leaf-blades sinuately spiny-denticulate. 1. L. virosa. 
Leaf-blades deeply pinnatifid. 2. L. Scariola. 
Involucres 12-20-flowered. 
Involucres over 1.5 cm. high: beak fully as long as the 
body of the achene. 
Involueres less than 1.5 cm. high: beak shorter than the 
he achene. 
Leaf-blades without spines on the margins or midribs. 
Leaf-blades entire or merely toothed. 
Leaf-blades, pr od id some of them, pinnatifid. 
Leaves glabro 
Leaves Bireute, at least their midribs. 
Lower leaf-blades n Ye beak of achene fully 
as long as the 
ae leaf-blades Wueually both entire and pinnatifid : 
ea 
. ludoviciana. 
3 
4. L.sagittifolia. 
4. L.sagittifolia. 
5 
. canadensis. 
hirsuta. 
chene much shorter than the body. . graminifolia. 
aL. Stem hirsute below, 6-20 dm. tall: leaf-blades oblanceolate 
l. L. 
to olio, merely s glaucous: inner bracts of the involucre 12-15 
mm wly corollas 
outer 
11- is) E id E eue body gradu 
i ved a the apex. —Fields, 
and roadsides, various provinces, Ga. E 
Tenn., Kans., and N. Y. Nat. of Eu. 
ario pir Stem nearly or quite gla- 
Noc leaf- blades oblong to 
in outline, pinnatifid, irs 
ner Bue of the proc 8-1 
o Miss, Mo., and Vt. Nat 
puis ee DC. Stem 4-15 dm. tall, glabrous: leaves hori- 
m Ae ades ong, sinuate-lobed or pin nnat tifa: involucres 16-20 mm. 
e inner us e lanceolate: ligules yellow: achene-body 4—4.5 mm. 
long. dee soil, ghee on wooded banks, various provinces, Tenn. to Tex., N. 
Dak., Minn., and A 
L. A eie Ell. Stem 9-30 dm. tall, glabrous: o m ps stem- 
leaves 8-30 c i A ct dentate: involuere s 10-20 m ong, the inner 
bracts narrowly lin rly so: ligules hee or EE achene-body 
5-3 mm. long, lo onger ia the be ee soil, ee woods, and shaded 
banks, various provinces, Ga. to Nebr., and 
L. canadensis L. Stem 9-30 dm. tall, glabrous or nearly so: blades of 
ae i eet 10-30 em. long, sinuate- -pinnatifid: involueres 10—12 mm. long, 
