264 
POLTPETALOUS OKDEKS. 
ing hairs. Leaves opposite or alternate, exstipulate. Calyx- 
tube adherent to the ovarj ; lirriib mostly 5-parted. Petals the 
same number, or twice as many as the lobes of the calyx. Sta 
mens perigynous, in several rows, distinct or polyadelphous. 
Ovary 1-celled, with parietal placentas ; style single. Fruit 
'^.apsular or succulent. Seeds few, or numerous ; embryo straight, 
in the axis of fleshy albumen. 
a. Properties : chiefly distinguished for their ba»r-like stings. 
Genus. — Mentzelia, Bartonia. 
456. Passiflorace^, the Passion-flower Tribe. — Herbs or 
shrubs^ climbing by tendrils. Leaves alternate, mostly stipu- 
late. Segals 5, united below. Petals 5, with a filamentous 
crown. Stamens 5, monadelphous ; anthers versatile, extrorse. 
Ovary 1-celled ; styles 3 ; stigmas dilated. Fruit mostly fleshy, 
or berry-like. Seeds numerous ; testa brittle, arilled ; embryo 
straight, inclosed in thin, fleshy albumen. 
a. Properties : many of the plants yield edible fruits, while others are bitter, 
astringent, and narcotic. 
Genus. — Passiflora. 
457. Papayace^, the Papaw Tribe. — Trees or shrubs^ some- 
times yielding an acrid milky juice. Leaves alternate, lobed. 
Calyx 5-toothed, minute. Corolla monopetalous, 5-lobed. Sta- 
mens 10, inserted on the throat of the corolla; anthers introise. 
Ovary free, 1-celled ; stigma 5-lobed. Fruit succulent or cap- 
sular, 1-celled, with parietal placentse. Seeds enveloped in a 
Uiose mucous coat ; embryo in the axis of fleshy albumen. 
Genus. — Carica. 
458. CucuRBiTACE^, the Gourd Tribe. — Juicy herbs.^ climbing 
by tendrils. Leaves alternate, palmate, rough. Flowers mo- 
noecious or dioecious. Sepals 4 or 5, united in a tube. Petals 
as many as the sepals, distinct, or more or less united, cohering 
with the calyx. Stamens 5, attached to the petals, distinct or 
variously united ; anthers sinuous. Ovary adhering to the 
calyx, l-celled, with 3 parietal placentae, which often project 
into the cavity, uniting in a Fig. i87. 
central column ; stigmas thick, 
velvety or fringed. Fruit a 
fleshy pepo, with a hard rind, 
and crowned by the scar of the 
calyx. Seeds flat, exalbuminous ; 
embryo straight ; cotyledons foli- 
aceous. 
a. Properties : an acrid principle abounds ; 
when this is diffused the fruits are edible, 
but when concentrated, they are poison- 
ous. 
