Spiraea hypericifolia. - Hypericum-leaved Spiraea, or, St. Peter's Wreath. - This is a very elegant shrub, producing its numerous small white flowers in long garlands, upon the delicate curving branches of the plant. The bush, when in flower, has the appearance of being covered with a light fall of snow. The foliage is elegant; it is in flower in May and June; grows about four feet high; the extremities of the branches are sometimes winter-killed; easily propagated by suckers, divisions of the root, or by layers, as all the species are.

S. Opulifolia. Nine-Bark

"An ornamental native shrub, found from Canada to Georgia; from five to seven feet high, distinguished for the abundance of its showy heads of flowers, and for its conspicuous fruit. The stem is rugged, with loose, gray bark, easily detached, and falling off. Flowers in hemispherical heads, on a short stalk, - each flower on a slender, downy thread; white, with a rose tinge."

S. Salicifolia. The Queen Of The Meadows

This is a very pretty native shrub, from two to four, and sometimes six, feet high, with terminal heads of neat, white, sometimes rose-tinted flowers, in June and July.

S. Tomentosa. Steeple Bush. Hard-Hack

This is a very common, leafy shrub, from two to five feet high, growing in wet ground, and distinguished in the flowering season for its long, tapering spire of purple flowers. A few years since, we ordered all the handsome Spiraeas from England, excluding all that we possessed. When they came into flower, we found among them, this old, familiar country friend. * It is, however, handsome when cultivated and pruned of the previous year's stems, which disfigure it very much, when growing in the pastures.

S. Prunifolia Plena. Double Plum-Leaved Spiraea

This is one of the most desirable species or varieties of the Spiraea, and is perfectly hardy. The following account is from the Gardener's Chronicle. "This charming shrub was introduced into Europe by Dr. Siebold, to whom our collections are indebted for so many novelties, only to be procured with the utmost difficulty. It deserves the attention of all amateurs, as well for its hardiness as its elegant habit and beautiful flowers. The Dutch traveller found it cultivated in the Japanese gardens, and supposes its native country to be Corea, or the north of China. It is a shrub, from six to nine feet high, and has upright, close, bushy, slender branches, which are covered with a smooth, ash-colored bark, that detaches itself at later periods in thin scales. The leaves are oval, or ovate-elliptic, rounded at their base, obtuse or a little acute at their apex, downy beneath, denticulated at the edge. The flowers, which grow by threes or sixes, cover the whole length of the branches, are as white as snow, and very double, in consequence of a complete abortion of their stamens. Their shape is exactly like that of the Ranunculus aconitifolius with double flowers, and their number and arrangement, with a light and elegant bright-green foliage, render this plant a charming addition to the shrubs which grow in the native air." It flowers in this climate in May.

S. Donglasii. Mr. Douglas's Spiraea

This shrub is from California, and has some resemblance to S. tomentosa, flowering in the same manner; flowers fine rosy-lilac, continuing in bloom from July till the autumnal frosts commence.

S. Sorbifolio - Pinnate-Leaved Spiraea

This is a vigorous shrub, a native of Siberia. It develops its handsome pinnate foliage very early in the* spring. The leaflets are serrated, or with notched edges. The flowers are yellowish-white, produced in large, dense panicles, in June. The flowers seem to be peculiarly attractive to the rose-bugs, which sometimes disfigure and spoil their beauty by the immense numbers which delight to revel in its sweets. This shrub propagates itself too fast, as it throws up its suckers in great profusion, and makes itself quite too common; otherwise it would be a desirable plant for the shrubbery.

S. Reevcsiana. Mr. Reeves's Spiraea

We consider this one of the most elegant and desirable species of the whole genus. The flowers are of a snowy whiteness, produced in clusters, the whole length of its graceful, arching stems, which, intermingled with the handsome foliage, produce a pleasing effect. The shrub is delicate in its growth, about four feet high, and flowers in June. It is propagated by cuttings, layers, and suckers.

S. Airaefolia

This is a very delicate species which we have in our collection, with exceedingly graceful foliage, with small heads of white flowers; two or three feet high.

S. Laevigata. Smooth-Leaved Spiraea

This species has smooth lanceolate leaves, without serrature or notch. The flowers are white, in compound racemes, somewhat fragrant. It is not very showy, but, in a collection, makes up a variety; about two or three feet high.

S. Trilobata. Three-Lobed-Leaved Spiraea

The leaves of this species are bluntly three-lobed, and toothed, or notched. The flowers are white, in stalked umbels, about three or four feet high.

Altogether, we do not know any genus of plants where the foliage is so diversified. When grouped together, they make a fine appearance, either in flower or foliage. There are many other species that have not come under our observation, which, no doubt, are as valuable for the shrubbery as those described.