Prunus. | XXVI. ROSACEA. 129 
These Genera are usually distributed into three Tribes, considered by 
some botanists as distinct Orders, viz. :— 
1. AMYGDALE®. Calyx deciduous. Carpell, free. Genus:—1, Prunus. 
2. Rosrm. Calyx persistent. Carpels 1 or more, free (but sometimes included 
in the closed calyx). Genera:—2. Sprrma; 3. Dryas; 4. Guum; 5. Rubus; 6. 
PRAGARIA; 7, PorENTILLA; 8. SrBBALDIA; 9, ALCHEMILLA; 10, SANGUISORBA; 11. 
PoTEeRiIuM ; 12, Aarimonia; 13. Rosa. 
3. Pomacrm, Calyx persistent, adherent to the ovary, the carpels of which are 
united, at least in the ripe fruit. Genera:—14. Pyrus; 15. Cratmaus; 16. Coto- 
NEASTER; 17. MESPILUS. . 
The double-flowering Kerria japonica, so frequently to be met with trained upon 
cottage garden-walls, formerly supposed to be a species of Corchorus, is now 
known to belong to the Rosacea. : 
1. PRUNUS. PRUNUS. 
Shrubs or trees, with undivided, toothed leaves, and small, free stipules, 
often scarcely visible; the flowers either in small bunches on a former 
year’s wood, or in racemes in the axils of young leaves. Calyx free, 5- 
lobed. Petals 5. Stamens numerous. Ovary of 1 carpel, containing 2 
pendulous ovules. Fruit a fleshy or juicy drupe, with a hard stone, smooth 
or rugged, but not wrinkled on the surface, containing 1, or rarely 2 seeds. 
A considerable genus, distributed over the whole of the northern hemi- 
sphere, and even abundant within the tropics, both in the new and the old 
world, but not extending into the south temperate zone. It is the only 
British genus with a stone fruit. 
Flowers in axillary racemes : ° » & Ps Padus: 
Flowers solitary or clustered, from leafless puds. 
Flowers single or two together, on short pedicels. - : . 1. P. communis. 
Flowers in clusters, on pedicels longer than the flower itself . 2. P. Cerasus. 
The well-known common Laurel and Portugal Laurel of our gardeners, 
are species of Prunus (P. Lauro-cerasus and P. lusitanicus), and have no 
affinity with the true Laurel of the ancients, which is our Bay-tree (Laurus 
nobilis). The Mahaleb (P. Mahaleb) and the P. semperflorens, both from 
the continent of Europe, are also frequently to be met with in our shrub- 
beries. The Apricot is another Prunus (P. armeniaca) ; the Almond, the 
Peach, and the Nectarine, belong to the genus Amygdalus, only differing 
from Prunus in the wrinkled surface of the stone. 
1. P.communis, Huds. (fig. 297). Blackthorn Prunus, Blackthorn 
or Sloe,—In the common, truly wild state, this is a much branched shrub, 
the smaller branches often ending in a stout thorn. Leaves ovate or 
oblong, stalked, and finely toothed, usually glabrous, but occasionally, 
especially the under sides as well as the young shoots, more or less downy. 
Flowers small, white, nearly sessile, solitary or in pairs, appearing before 
the leaves. Fruit small, globular or shortly ovoid, nearly black, with a 
bluish bloom. . 
In hedges, thickets, and open woods, common in Europe and in Russian 
and central Asia. Abundant in Britain. J. early spring. The Bullace 
is a variety of a somewhat taller growth, and less thorny, with the leaves 
rather more downy, and the fruit rather larger and globose, black or yellow, 
and less acrid; it has been distinguished under the name of P. insititia, 
Linn, Itis more abundant and more marked in south-eastern Europe and 
central Asia than with us. The Damson and the numerous varieties of 
Plum of our gardens, although growing into thornless trees, are believed to be 
K 
