This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
Herbs, rarely frutescent. Leaves membranous, sessile or petiolate, entire, lobed, or pinnatifid. Flowers usually large and showy, axillary, sessile, or pedunculate. Calyx-tube produced above the seed-vessel, lobes often reflexed and deciduous. Petals 4, not clawed, entire. Stamens 8. Capsule membranous or woody, costate, clavate, tetragonal, polygonal or winged. Seeds few or many, with or without an appendage. There are nearly 100 species, with the exception of one Tas-manian species, of American origin. The etymology of the name is not satisfactorily explained. Godetia was formerly separated on insufficient grounds; but it may be remarked that there are no yellow-flowered species belonging to this section, and in OEnothera they are either yellow or white, with one or two exceptions. The species are very similar in appearance, there-fore a small selection will suffice.
1. CE. rubicunda, syn. Godetia rubicunda (fig. 106). An erect annual about 2 feet high with lilac-purple flowers having a deeper coloured blotch at the base of each petal. One of the most desirable species. Under cultivation it has produced a beautiful blush-white and other varieties.
2. CE. Whitneyi, syn. Godetia grandiflora. - An annual of recent introduction. This is a magnificent species, of dwarf compact habit, bearing a profusion of rosy-red flowers blotched with crimson, and from 3 to 4 inches in diameter.
Other handsome species of the Godetia section are: - (E. roseo-alba, rosy purple and white, (OE. Lindleyana, purple, also with double flowers, and (E. reptans, a trailing species with rose-purple spotted flowers.
3. CE. biennis. Evening Primrose. - This is the species first introduced, and now become naturalised in some localities. It is a tall pubescent plant with yellow flowers about 3 inches in diameter. The peculiarity of this and some other species is, that the flowers do not expand till towards evening.
Fig. 106. CEnothera rubicunda. (1/4 nat. size.)
4. CE. Fraseri. - This is one of the best yellow-flowering perennial species. It has rich dark-green foliage, and blossoms abundantly throughout the Summer.
5. CE. taraxacifolia. - A dwarf perennial with pinnatifid le a v e s and large pure white flowers.
CE. acaulis and CE. speciosa (fig. 107) are dwarf perennial white-flowered species; (E. chrysantha and (E. Missouriensis have yellow flowers, and the latter is of prostrate habit, and one of the most desirable. Amongst annuals may be cited CE. macrantha and CE. odordta, both yellow.
Fig. 107. (CEnothera speciosa. (1/6 nat. size.)