NM ¥ CVAGIN ACH. At. * 
Corolla wanting, its place being taken by the corolla-like 
calyx, which opens in the Jate afternoon or evening and closes in 
the morning, and is campanulate to tubular and, except in 
Mirabilis multiflora and Hermidium, is very thin, delicate and 
soon wilting but persistent, its base thickened around the single 
seed, when the involucre is one-flowered it presents all the 
appearance of a calyx; stamens often united at base, 1-7, normally 
5, filaments attached to the calyx, slender and with rounded 
anthers; style and stigma simple; ovary 1-celled and 1-seeded; 
flawers normally pink, rarely purple, white or yellow, usually 
collected in heads or clusters and always surrounded by separate 
or united bracts (bracts entirely absent in Boerhavia spicata var. 
Palmeri), but they are readily distinguishable from a true calyx, — 
except rarely in Allionia, by there being more than one flower 
in the cup formed by the bracts; fruit often grooved, ribbed or 
winged, enclosing the free akene, which has a membranous coat; 
embryo coiled around the mealy albumen and, in Abronia only, 
apparently of a single leaf; weak herbs with brittle stems and 
swollen joints; leaves mestly opposite and oblique, normally 
fleshy when fresh and rarely membranous when dry, petioled, 
without stipules, entire or only wavy on the margins, except 
Berhavia annulata, and often pubescent or glutinous. Probably 
all species are vespertine. This is a family of 20 genera and 

e following study of the DP bas agree is confined chiefiy to the 
region oe ih Great Plateau, though a few Mexican and central Texas 
species are mentioned. 

