1152 CARDUACEAE 
mm. long, sparingly ciliate: heads drooping, sessile: bracts of the involucre cuneate, 3 
mm. high, ciliolate: corolla 2 mm. long ; lobes spreading or recurved. 
In swamps and low ground, Mississippi and Louisiana. Fall. 
6. Iva microcéphala Nutt. Annual, glabrous or nearly so, slight. Stems erect, 
3-9 dm. tall, much branched above, the branches slender, erect or ascending: leaves often 
alternate ; blades narrowly linear, 2-5 cm. long, acute, entire, or slightly toothed : heads 
numerous, sessile or nearly so: bracts narrowly linear to linear-filiform, surpassing the 
heads: involucres 3-6-flowered, campanulate, 2 mm. high: bracts oblong to cuneate, 
obtuse to retuse at the apex : fructiferous flowers 3: corolla nearly 2 mm. long: achenes 
about 1 mm. long. 
In dry pine lands and waste places, Georgia and Florida. Summer and fall. 
7. Iva angustifolia Nutt. Annual, strigose or hirsute-strigose. Stems erect, or as- 
cending, 5-12 dm. tall, branching above: leaves various; blades linear or linear-lanceolate, 
4-6 em. long, or the upper 2-4 cm. long, narrowly linear or linear-filiform, acute, entire 
or sparingly toothed, ciliate: heads numerous, often crowded : bracts narrowly linear or 
linear-filiform : involucre turbinate, 3 mm. high, bristly: bracts partially united into a 
cup, the free portions ciliate: fructiferous flowers solitary: corolla 3 mm. long ; lobe. 
ovate, acutish, recurved : achenes cuneate-obovate, 3 mm. long. 
In river bottoms, Arkansas to Louisiana and Texas. Spring to fall. à 
8. Iva xanthiifólia (Fresen.) Nutt. Annual, bright green. Stems erect, 0.5-2 m, 
tall, much branched, glabrous below, pubescent or merely puberulent above : leaves chiefly 
opposite; blades broadly deltoid, ovate to lanceolate or elliptic above, 3-nerved, 8-16 cm. 
long, acuminate, coarsely and irregularly dentate, truncate to cuneate at the base, canes- 
cent or pale-puberulent beneath; petioles as long as the blades or shorter above: heads 
nearly sessile, 2-3 mm. broad, in panicled spikes: bracts of the involucres in 2 series, the 
outer broadest below the middle, the inner broadest above the middle: staminate flowers 
10-15: fructiferous flowers usually 5, with rudimentary corollas: achenes cuneate, usually 
5, fully 2 mm. long, striate. 
In moist soil or in waste places, Northwest Territory to Michigan, Wisconsin, the Indian Terri- 
tory, New Mexico and Utah. Summer. 
FAMILY 2. CARDUACEAE Neck. THISTLE FAMILY. 
Herbs or rarely shrubs, or sometimes trees in the tropics, with watery or 
resinous, or rarely milky sap. Leaves opposite or alternate, sometimes all basal, 
without stipules. Flowers perfect, pistillate or neutral, or sometimes monoecious 
or dioecious, aggregated on a receptacle, surrounded by an involucre. Recep- 
tacle naked or scaly, smooth, pitted or honey-combed. Involucre of distinct or 
partially united bracts in one or several series. Calyx of bristles, awns, Or 
scales, or crown or cup-like, forming pappus at maturity, or wanting. Corolla 
of 5 partially dnited petals, 5-lobed or in the case of the marginal flowers of the 
head the corolla is often produced on one side into a ligule ; when ray-flowers 
are present the head is said to be radiate, when wanting it is said to be discoid. 
Androecium of 5 stamens partially adnate to the corolla tube: anthers often ap- 
pendaged at the apex and sometimes at the base, united into a ring (syngene- 
cious) except in Kuhnia. Gynoecium 2-carpellary. Ovary inferior, 1-celled. 
Stigmas of the fructiferous flowers 2. Ovule solitary. Fruit an achene. Seed 
erect. Endosperm wanting. 
£X Psal. Aere viro regalar, corollas. he middi 
igmatic lines at the base of the stigma or below the m e. 
Stigmas filiform or subulate, hispidulous. TRIBE I. VERNON TRAE, 
_Stigma more or less clavate, papillose-puberulent. TRIBE II. EUPA 
Bie pe ee E tothe Pp of the stigma yd to the appendages. : 
a. Anthers without elongated appendages at the top. 
Anther-saes tailed at the D Y d TRIBE IV. INULEAE. 
Anther-sacs not tailed at the base. 
Receptacle naked. 
Bracts of mo well imbricated. od 
ORDR of the perfect flowers with terminal appen- iunt HE ASTEREAE. 
ages. ; 
Stigmas of a Lees flowers with truncate or hairy 
or papillose tips. LENIEAE. 
Braets of the involucre herbaceous. Trine VI. HE EAE. 
> prets of the involucre ary and ecarioni. a ^ Trise VII. ANTHEMID 
racts of the involucre little if at all imbricated, excep EAE. 
R ^ men rhe broad outer ones overlap the inner. TRIBE VIII. SENECION 
eceptacle chaffy. EAE 
* Bracts of thelnvoluere herbaceous, sometimes foliaceous. TRIBE V. HELIANTH 
