48 
stalked, oblong-ovate, acute, slightly hairy leaflets, gradually narrowed 
and rounded at base, bright green above and pale below. The branch- 
lets of this shrub, the leaf stalks, the stem of the flower-clusters and 
the calyx of the flowers are thickly covered with gland bearing hairs. 
The flowers are arranged in erect axillary racemes shorter than the 
leaves, and are interesting from the contrast between the pure white 
petals and the dull red calyx. This tall shrub differs chiefly from the 
arborescent R. viscosa in habit and in the less viscid secretions from 
the glands which are common to the two plants; and it is not improb¬ 
able that when better known, they may prove to be varieties of one 
species. Whatever its specific rank, R. Hartwigii is an attractive and 
useful addition to the hardy shrubs which flower here at the end of 
June. 
Cornus Amomum, the Silky Cornel, is just beginning to open its 
flower-buds. In cultivation it is not a satisfactory plant unless it can 
be given sufficient room for its wide-spreading branches to extend freely 
and spread over the ground. When crowded by other plants the 
branches become erect and it loses its real beauty and value. To be 
seen at its best this Cornel should have a clear space with a diameter 
of not less than twenty feet in which to spread. It is well suited for 
the front of groups of trees and shrubs, and there is no better shrub 
to plant by the margins of ponds and streams where its long branches 
can hang gracefully over the water. Its purple stems are attractive 
in winter, and the bright blue fruits which ripen in the autumn add to 
the value of this native shrub. In the Cornel Group, at the junction 
of the Meadow and Bussey Hill Roads, there is a good specimen of this 
plant, and its value for planting near water can be seen on the bor¬ 
ders of the small pond in the rear of the Cornel Group. 
Cornus alternifolia is also in flower. It is a tree growing sometimes 
to the height of thirty feet with long branches spreading at right 
angles from the stem, from which rise lateral branchlets bearing the 
terminal flower clusters. The distinctive character of this Cornus is 
found in the alternate leaves, the leaves of the other American species 
being opposite. The handsome blue or rarely yellow fruit ripens in 
October. Cornus alternifolia has always proved difficult to transplant 
and for a long time was not well represented in the Arboretum, but 
there are now several healthy plants growing on the slope at the right 
hand side of the Roslindale entrance. There is also a plant which has 
grown spontaneously at the eastern base of the hill on which the Juni¬ 
per collection is established. The Cornus from eastern Asia, Cornus 
controversa, is another species with alternate leaves and with spread¬ 
ing branches. It is a larger and handsomer tree than its American 
relative with larger flower-clusters. In western China it sometimes 
grows to the height of sixty feet and now promises to grow to a large 
size here and to become one of the important trees introduced by the 
Arboretum into the United States. This Cornel flowers here at the 
end of May or early in June. 
