ROBINIA DUBIA (_syns R. echiuata_ and _R. ambigua_).--A very pretty

garden hybrid form, said to have for its parentage R. Pseud-Acacia and

R. viscosa. It is of quite tree-like growth and habit, with unusually

short spines, and Pea-green foliage. The flowers are produced pretty

freely, and are of a pale rose colour, and well set off by the

light-green leaves, over which they hang in neat and compact spikes.

R. HISPIDA.--Rose Acacia. North America, 1743. Amongst large-growing

shrubs this is certainly one of the most distinct and handsome, and at

the same time one of the hardiest and readiest of culture. Under

favourable conditions it grows about 16 feet high, with large oval or

oblong leaflets, and having the young branches densely clothed with

bristles. The flowers, which are individually larger than those of the

False Acacia, are of a beautiful rosy-pink, and produced in June and

July. It is a very ornamental, small growing species, and one that is

peculiarly suitable for planting where space is limited. R. hispida

macrophylla (Large-leaved Rose Acacia) is rendered distinct by its

generally more robust growth, and by its larger foliage and flowers. The

species, however, varies a good deal in respect of the size of leaves

and flowers.

R. PSEUD-ACACIA.--Common Locust, Bastard Acacia, or False Acacia. North

America, 1640. A noble-growing and handsome tree, with smooth shoots,

and stipules that become transformed into sharp, stiff spines. The

flowers are in long racemes, pure-white or slightly tinged with pink,

and with a faint pleasing odour. This species has been sub-divided into

a great number of varieties, some of which are very distinct, but the

majority are not sufficiently so to warrant special attention. The

following include the best and most popular kinds:--R. Pseud-Acacia

Decaisneana, a distinct form bearing light pinky flowers; R.

Pseud-Acacia Bessoniana, with thornless branches and a dense head of

refreshing Pea-green foliage; R. Pseud-Acacia angustifolia, with narrow

leaves; R. Pseud-Acacia aurea, a conspicuous but not very constant

golden leaved form; R. Pseud-Acacia inermis, of which there are weeping,

upright, and broad-leaved forms, has narrow leaves that are glaucous

beneath, and the characteristic spines of the species are wanting or

rarely well developed. R. Pseud-Acacia monophylla is very distinct, the

leaves being entire instead of pinnate; while R. Pseud-Acacia crispa has

curiously-curled foliage. Then there is the peculiar R. Pseud-Acacia

tortuosa, of ungainly habit; R. Pseud-Acacia umbraculifera, with a

spreading head; R. Pseud-Acacia sophoraefolia, the leaves of which

resemble those of Sophora japonica; and R. Pseud-Acacia amorphaefolia,

with very large foliage when compared with the parent tree. The above

may be taken as the most distinct and desirable forms of the False

Acacia, but there are many others, such as R. Pseud-Acacia colutoides,

R. Pseud-Acacia semperflorens, and R. Pseud-Acacia Rhederi, all more or

less distinct from the typical tree.

R. VISCOSA (_syn R. glutinosa_).--Clammy Locust. North America, 1797.

This is a small-growing tree, and readily distinguished by the clammy

bark of the younger shoots. Flowers in short racemes, and of a beautiful

rose-pink, but varying a good deal in depth of tint. It is a valuable

species for ornamental planting, and flowers well even in a young state.

Few soils would seem to come amiss to the Acacias, but observations

made in many parts of the country conclusively prove that the finest

specimens are growing on light, rich loam overlying a bed of gravel.

They are propagated from seed, by layers, or by grafting.