CORRIGIOLACEAE | 479 
maturity.— (COTTON WEED. area ene ere and sandy old fields, Coastal 
Plain, Fla. to Miss. and Ga.; adv. in Del.—All year 8S. 
Famity 5. CORRIGIOLACEAE —WuirLow-wogT FAMILY 
Herbs, but often firm or woody at the base. — opposite, stipu- 
late: blades entire. Flowers perfect, eymose. Calyx 
s awned or cuspidate at the sd 
or 5 stamens borne on the margin of the minute or long 
hypanthium. Gynoecium mostly 2-carpellary. wanes 1-celled. 
utricle or an achene. Seed ee —About 20 genera and 100 species 
of wide uero. distributio 
Hypanthium very small: stamens borne on its edge under the ovary. 
Tribe I. PARONYCHIEAE. 
Hypanthium well-developed, nearly or quite as long as . 
the ealyx: stamens borne high up on its edge. Tribe II. SIPHONYCHIEAE. 
I. ner dd Wee 
Sepals with ue awns on the back of the hood. 1. PARONXCHIA. 
or mucro on the back of tno hood. 
lender. 
turgid at the base: sepals narrow, elongate: 
r-sacS narrow. 2. GASTRONYCHIA. 
Calyx Bot turgid at the base; sepals broad: anther- 
saes bro ad: 3. ANYCHIASTRUM. 
Style wanting or very short. 
Sepals mucronate. 4. ANYCHIA. 
epals umbonate at the apex. 5. NYACHIA. 
II. SIPHONXCHIEAE 
Flowers subtended by eee bracts at maturity. 
Sepals short and prose, a mucro: oe urceolate. 6. SIPHONYCHIA. 
e e nd n o Dno ut a mu : flower subu- 
late or Bio Comum te. 7. ODONTONYCHIA. 
Flowers subtended by indurated br acts at maturity. 8. GIBBESIA. 
1. PARONYCHIA [Tourn.] Adans. Annual or perennial herbs, with 
short tufted or matted branches and longer, often erect flower-stems. Leaves with 
narrow, ofton bristle-like blades. Sus eompaet or congested. Sepals narrow, 
hooded at the apex, and terminating in a cusp or awn, sometimes alternatin 
with E bristles or tooth-like ee ioe included. —— bs ‘species, 
natives of warm regions.—Sum.—fall—WHITLOW-WworRTs. NAILW 
Cymes nearly naked: calyx glabrous: bracts bristle-like. 1. P. dichotoma. 
Cymes densely silvery bracted: calyx pubescent: bracts linear. 2. P. argyrocoma. 
1. P. dichotoma (L.) Nutt. Plants in tufts: leaf-blades bristle-like, 1-3.5 
cm. long, often Maa anager flowering stems 1—4 dm. tall, glabrous or 
a sepals becom . long, 
a short 
ORT.) —Roc d 
provinces N of Me SN Plain, N.C.t 
Tex., W. Va. 
2. P. argyrocoma (Michx.) Nutt. Plants 
7a o s Po -o nearly so, flat, 
tops, 
cliffs, and rocky slopes, often in acid soil, 
Blue "Ridge and adj. provinees, Ga. 
and. Va.— Carpets of this ee on the nie 
