CARDUACEAE 1319 
Spr.-fall.—Usually growing in water or at least in n soft m ud. Sometimes very 
densely matted and Gea ere on account of the very numerous whorled 
leaves and the numerous stems each with an erect small head. 
7T. AGERATUM L. Annual or rarely perennial, stiff. herbs or partly 
woody plants. Leaves usually opposite: blades toothed. Heads cor ymbose. 
Involuere campanulate. Receptacle elevated. Flowers blue, purple, pink, or white. 
Corolla-lobes erect, deltoid. Anther-appendages ovate. Achene 5- -angled short. 
Pappus of several short blunt or long slender- -tipped scales, or cup-like or erown- 
like.—About 30 species, tropical American, several widely eultivated.— 
AGERATUMS 
Pappus cup-like or crown-like, the scales very short: sais glabrous: foliage 
glabrous: leaves succulent. A. littorale. 
Pappus of distinct Scales as lo ong as the Me cues 
Involucre over 4 mm ; bracts long- ET i 
decidedly longer than s 'ach 2. A. Houstonianum. 
Involucre less than 4 mm. hi igh: ' bracts Short-tipped : 
pappus about as long as the ache ene, . A. conyzoides. 
1. A. littorale A. Gray. Stem 2-7 dm. ta ll, glabrous, often branched at the 
base: leaf- E ovate, 1-5 em. long, crenate- -serrate, usually cuneate at the 
ase: corymbs terminating long p oo 
j olucre 4 m 
the numerous blue flower-heads. 
eultivated locally. 
2. A. Houstonianum Mill Stem 3-11 dm 
tall, ed buda De with crisped 
hairs, som s branched: leaf-blades ovate 
to deltoid poss "ne em, long, crenate, 
thick: involucre about 5 mm. high in an- 
Fed braets subulate to linear- vp copiously pubescent: > nearly 
3 mm. long: achene about 2 mm. long, stout: pappus-scales near ly 2 
a the slender tip less than e as long as the body.—Pinelands and cult. 
grounds, Fla. Nat. of Mex.—( .)—Sum —fall. -——Commonly cultivated 
for ornament. The flowers a: are very fragran nt. 
A. conyzoides L. St ‘dm. tall, sparingly p Or A ví 
glabrous, earn TA anched: ead: nen ovate to deltoid- -0vate, 1.5-4 cm. long, 
h: involuere about 3 mm. high in an bs esi * bracts subulate E 
ur subulate, sparingly pubescent: corolla nearly 2 mm. long: e 1.5 m 
long, slender: pappus-scales about 1.5 mm. long, the p tip fully Ee 
eR. the small body. EA -places ond cult. grounds, Coastal Plain, 
Fla. to Miss. and N. trop. Am.—Sum.—fall.—Has smaller heads 
than m precede species md. is pe commonly cultivated. 
8. MIA Sch h. Bip. Shrubs or perennial herbs, with much-branched 
stems. Leaves oped e: blades broadest below the middle, often coarsely 
toothed. Heads borne in corymbs, relatively few-flowered. Flowers lilae, pale- 
purple, bluish-purple, or white. Involucre narrowly ovoid or stout-cylindrie: 
