CLXXIX.— THE ROSE-BAY. 
Epilobium angustifolium Linne. 
T HE Onagracece are a considerable Family, belonging mainly to Northern 
Temperate regions and mostly herbaceous. They take their name from 
Onagra, a pre-Linnasan name for the Evening Primroses, now known as (Enothera . 
Most of the species are perennials with exstipulate simple leaves, polysym metric 
flowers with their parts in twos or fours, valvate sepals, contorted petals, and inferior 
ovary with a single style and central placentation. The tubular floral receptacle is 
generally prolonged as a “calyx-tube” beyond the region in which it is adherent to 
the ovary. The Family includes many ornamental genera of garden flowers, such as 
Clarkia, (Enothera , and, above all, Fuchsia; but has no medicinal or other applications 
of economic importance. 
The genus Epilobium was so named by Conrad Gesner, from the Greek ini , epi , 
upon, 'kofiiov, lobion, a pod, with reference to the epigynous character of the corolla, 
a character which, as a matter of fact, it shares with the other members of the Family. 
It includes upwards of a hundred and fifty species, twelve of which are British, 
besides a great number of natural hybrid forms. Most of them are herbaceous and 
perennial, with slender rooting underground stems or “ stolons,” which render them 
somewhat difficult plants to eradicate from gardens. The flowers are mostly pink or 
white, tetramerous, and polysymmetric, with a long “ calyx-tube,” deciduous sepals, 
bilobed petals, two whorls of four stamens each, differing in length, and a slender 
style. The fruit is a long four-chambered capsule dehiscing loculicidally and septi- 
fragally by four valves which coil back from above downward, leaving the numerous 
seeds attached to the central axis. The seeds are small, oblong, and brown, and are 
each surmounted by a tuft or coma of long silky white hairs which act as most 
effective aids to their dispersal by wind. Honey is secreted at the summit of the 
ovary, and in wet weather the long ovaries bend, so that the flowers droop and their 
pollen is thus protected from the rain. 
Among the British representatives of the genus there is a considerable range 
of difference in the size of the flowers and in the time of maturation of anthers 
and stigmas with reference to cross- or self-pollination. The Rose-bay ( Epilobium 
angustifolium Linne) has large flowers in which autogamy, i.e. self-pollination is 
almost impossible. It represents a section or sub-genus to which Scopoli gave the 
appropriate name Chamcenerium or Dwarf Oleander, from the Greek ^dp at, chamai, 
on the ground, and vrjpiov, nerion, oleander. The species of this group have no 
“calyx-tube,” the sepals being divided down to the summit of the inferior ovary: 
their petals are unequal, the two anterior ones being smaller than the posterior 
two, so that the flower is zygomorphic or monosymmetric : both stamens and style 
ultimately bend over so as to hang downwards from the centre of the vertically placed 
blossom ; and the leaves are scattered. Rose-bay was the first plant in which 
