304 THE GENTIAN FAMILY. [Chlora. 
IV. CHLORA. CHLORA. | 
Glaucus annuals, with yellow flowers. Calyx deeply divided as in 
Erythrea, but into 8 lobes. Corolla-tube very short; the limb spreading, 
8-lobed. Stamens 8. Style persisting on the capsule as in Gentian. 
Besides the British species, the genus includes one or two south European 
ones. | 
1, C. perfoliata, Linn. (fig. 680). Perfoliate Chlora, Yellowwort.—An 
erect, rather stiff annual, 2 or 3 inches to a foot high, of a pale glaucous 
green. Radical leaves in a spreading tuft, those of thestem in distant pairs, 
broadly connected together at the base, so that the stem appears to pass 
through them, whence the specific name. Flowers of a bright yellow, in 
rather loose terminal cymes; the corolla nearly rotate. 
In dry pastures, and waste places, generally confined to limestone dis- 
tricts, in western, central, and southern Europe to the Caucasus. In Britain, 
limited to England, where it is local, and Ireland. £1. summer. 
V. MENYANTHES. BUCKBEAN. 
A single species, distinguished as a genus from Limnanthemum by its 
compound leaves and the capsule opening in 2 valves. 
1, M. trifoliata, Linn. (fig.681). Common Buckbean, Buckbean or Marsh 
Trefoil.—An aquatic herb, with creeping rootstock and densely-matted 
roots. Stem short, creeping or floating, with a dense tuft of leaves, con- 
sisting each of a long stalk, sheathing at the base, and 3 obovate or oblong 
leaflets, 1 to 13 inches long. Flowers white, tinged externally with red, in 
an oblong raceme, on a peduncle of 6 inches to a foot, proceeding from the 
base of the tuft of leaves. Calyx short, with rather broad green lobes. 
Corolla campanulate, deeply 5-lobed, and elegantly fringed on the inside 
with white filaments. 
In wet bogs, and shallow ponds, in Europe, Russian and central Asia, 
and North America, extending into the Arctic regions. Diffused all over 
Britain. Ll. summer, rather early. 
VI. LIMNANTHEMUM. LIMNANTH. 
Aquatic plants, with simple, broad, floating leaves and yellow flowers. 
Calyx 5-cleft. Corolla nearly rotate, 5-cleft, slightly fringed within at 
the base. Capsule bursting irregularly when ripe. 
A small genus, represented by some species or variety in the fresh waters 
of most of the temperate or tropical parts of the world. 3 
1. &.nympheeoides, Link. (fig. 682). Common Limnanth.—The long 
stems creep and root at the base, branch and ascend to the surface of 
the water, bearing a single leaf at each upper branch, and a terminal float- 
ing tuft of leaves and peduncles. Leaves on long stalks, and deeply 
cordate, like those of a Waterlily on a small scale. Peduncles as long as 
the leafstalks, each with a single, rather large, yellow flower. JZ. pelia-— 
tum, Gmel., Villarsia reniformis, Linn. 
In ponds and.still waters, throughout Europe and central and Russian 
Asia, except the extreme north; extending eastward to China. Found in 
