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.
A small genus of deciduous shrubs of dwarf habit. Branches slender. Leaves simple or compound, glabrous. Flowers drooping, yellow, appearing towards the end of Winter or beginning of Spring, solitary from the axils of the previous year's leaves. Corolla 4-lobed, campanulate. The three known species are from China and Japan. Mr. Forsyth, after whom this genus was named, was gardener at Kensington Palace.
1. F. viridissima. - Leaves all simple and quite entire, linear-lanceolate or oblong, acute. Flowers abundant; peduncles much shorter than the flowers, covered with small scaly bracts. Calyx-lobes oblong, obtuse, shorter than the corolla-tube. Style always (?) longer than the stamens.
2. F. suspensa (fig. 167). - Leaves simple and trifoliolate on the same branch, toothed; central leaflet much larger than the lateral ones. Flowers few, scattered on the very slender branches. Peduncles slender, nearly naked, exceeding the flowers in length, bracteate at the base only; some of the bracts from 3 to 6 lines long. Calyx-lobes lanceolate, acute, equalling the corolla-tube. Style always (?) shorter than the stamens.
Fig. 167. Forsythia suspensa. (1/4 nat. size.)
F. Fortunei is a newly introduced species with simple broadly ovate leaves and golden yellow flowers.