HYDRANGEA ARBORESCENS.--North America, 1736. This is a plant of large

growth, but the flowers are greenish-white, and by no means conspicuous.

H. HORTENSIS (_syn Hortensia opuloides_).--China, 1790. This is an

old-fashioned garden shrub that is only hardy in the south and west of

these islands and in the vicinity of the sea. In some of the forms

nearly all the flowers are sterile, the calyx-lobes being greatly
r /> expanded, and in others the outer flowers only are sterile. According to

the nature of the soil the flowers vary much in colour, some being pure

white, others pink, and others of varying shades of blue. There are some

very beautiful and distinct varieties, such as H. hortensis japonica; H.

hortensis Otaksa, with large panicles of sterile blue flowers; H.

hortensis rosea-alba, with large rosy flowers; H. hortensis Thomas Hogg,

a very free-flowering and welcome form; H. hortensis mandschurica, and

H. hortensis stellata flore-pleno, with partially double flowers, are

worthy of attention.

H. PANICULATA.--Japan, 1874. This is one of the most distinct species,

in which the flower-heads are elongated, not flat, as in most other

species, and from which the finest form in cultivation has been

obtained. This is H. paniculata grandiflora, in which the flowers are

sterile and pure white, forming large panicles often a foot in length.

It is a magnificent variety, and, being perfectly hardy, should be

extensively planted for ornament. The flowers are produced in late

summer, but remain in good form for fully two months, dying off a rich

reddish hue.

H. QUERCIFOLIA.--Oak-leaved Hydrangea. Florida, 1803. This species has

neatly lobed leaves, and terminal panicles of pinky-white, but partially

barren, flowers.

H. SCANDENS.--Climbing Hydrangea. Japan, 1879. This is not very hardy,

but with the protection of a sunny wall it grows freely.

The Hydrangeas require a rich, loamy soil, and, unless in maritime

districts, a warm and sheltered situation. They are readily propagated

by means of cuttings.