CARDUACEAE 1469 
. maritima (L.) Rydb. Stem and branehes 1-3 dm. tall, often lp 
"n blades 2—4 cm. long ; blades e atifid, the segments spreading, fles 
involucre 10-12 mm. wide; bracts elliptic, obtuse, brown-margined: n 
flowers 15-30; iol white, 8-11 mm. PaL JOH cuneate, 2-2.5 mm. long, 
rugose on the back an bet ween the corky ri ibs pappus-crown toothed.—Bal- 
S. e waste-places, dd istal Plain d adj. prov inces, Ala. to Pa. and Mass. 
Nat. of Eu.—Spr.-fal 
- MATRICARIA [Tourn.] L. Annual or perennial, branehing herbs, 
but sometimes partly woody. Leaves alternate: blades lobed, dissected, or pin- 
nately divided. Heads corymbose. Involu- 
ere saucer-shaped to hemispheric: bracts 
somewhat imbricate in 2-4 series, narrow. 
Receptacle convex, naked. ay- rs 
usually present, several, pistillate, fruit- 
producing: corollas with narrow or broad 
ligules, white in our species. Disk-flowers 
numerous, perfect, fruit-producing: corollas 
differentiated, the lobes deltoid. Achene 
subeylindrie, 5-10-angled or 5-10-ribbed. 
Pappus in both ray and disk a lobed crown. 
—About 100 species, widely distributed. 
. M. Parthenium L. Stem 2-7 dm. tall, striate: leaf-blades broad, Md of 
the lower ones at least, twice pinnately parted, the d incised: involucre 
7-10 mm. wide; outer bracts a eluate d acute; inner bracts eae -ellip- 
tic, 2.5-3 mm. long, acute or obtu ligules white, m mm. long: disk cream- 
colored: achene 1.5 mm. long, 8-10-ribbed; pappus a toothed crown. [Chrys- 
anthemum Parthenium | (L.) rnh ee )-—Roadsides, fence-rows, 
A 1d waste-places, various proces to Ohio and N. B.; also Calif. 
o Wa sh. Nat. of Eu.—(V. I., Mez., ra id.) eum —fall. 
110. LEUCANTHEMUM [Tourn.] Mill. Perennial herbs with root- 
tocks. Leaves alternate: blades toothed or entire, or sometimes pinnatifid. 
Died solitary at the ends of the stem and 
branches. Involuere saucer-shaped: bracts 
somewhat imbricate in 2—4 series, narrow. 
Receptaele flat or convex, naked. Ra ay- 
flowers usually present, 10-25, pistillate and 
fruit-producing: corollas with white ligules. 
Disk-flowers numerous, perfect, fruit-pro- 
ducing: corollas yellow, the tube en) 
shorter than the front the lobes lanceo- 
late. Filaments adnate to the be 
Achene cylindric or ed so, 10-ribbed or 
10-angled. Pappus wanting or obsolete, or 
in the ray a mere crown.—About 20 species, 
natives of the northern hemisphere. 
