DICTYOGENOUS PLANTS. 321 
The Littacem, the typié¢al family of the group, are herbaceous 
plants, shrubs, or trees, with bulbs, tubers, rhizomes or fibrous 
roots. The leaves are narrow and sword-shaped, with parallel 
veins, only a very small number expanding into broad blades 
with diverging veins. The flowers are perfect—conspicuous, in 
spikes, heads, and clusters, umbels or panicles generally large 
and showy. 
They are all water-plants, with erect and leafless'stems, narrow 
leaves dilated at the base, and pedicelled perfect flowers, form- 
ing a terminal umbel, subtended by three 
membranous bracts, a perianth with six 
divisions, the three outer petals slightly . wisn & 
coloured and distinct from the sepals, which Pee. ei 
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are larger and more highly coloured. Stamens , N , 
nine, with free ovary, consisting of six car- i a 
pels more or less united by the ventral suture, 
The style is short, terminating in a lateral 
stigma. 
The Alismacee are aquatic plants, float- 
ing on ponds or growing in swampy places, 
distinguished from other orders of the same 
group by the sepals and petals being per- 
fectly distinct from each other both in colour 
and position. The root is usually a peren- 
nial creeping rhizome. The flowers form BY || 
umbels, racemes, or panicles. The leaves ex- iL 
pand into a broad blade with parallel veins. ae 
The Water Plantains, as they are sometimes ——— ee | 
called, are known by their numerous carpels, and imperfect floral 
envelope. They are chiefly natives of Northern regions, but 
several Sagittarias are found in the tropics of both hemispheres. 
Crass V.—DIcryoGEns. 
Among the Monocotyledons of Jussieu and Endogens of later 
botanists there is a small class of plants which are referable to — 
Endogens in the structure of the embryo, but which more 
_ Tesemble Exogens in a broad net-veined foliage, which usually — 
disarticulates with the stem, their small green flowers nearly 
Y 
