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than most shrubs they can support shade, and their ability to grow and 
flower under trees gives them a special value for the undergrowth of 
border plantations. 
It is unfortunate that the type of the genus and the only species 
in the gardens of the eighteenth century, Philadelphus coronarius, is 
now so rarely found in any but the really old-fashioned gardens of New 
England, for it is a delightful plant and the flowers of no other Phila- 
delphus are more pleasantly fragrant. There are in the Arboretum 
collection varieties of this plant with double flowers of which the var. 
deutziaeflorus, with narrow petals, is the handsomest; a variety with 
narrow leaves (var. salicifolia) is more curious than beautiful, and a 
dwarf compact form which never flowers, and one with yellow leaves, 
are more interesting to those who like monstrosities than to the lovers 
of beautiful plants. Among American species the handsomest are 
Philadelphus inodorus, P. pubescens and P. microphyllus. The first 
of these is by some persons considered the handsomest of the Syringas 
in the Arboretum collection. It is a species of the southern Appalachian 
region and a shrub six or seven feet tall, with gracefully arching 
branches which are studded from end to end with large, cup-shaped, 
snow white, scentless flowers. Although this shrub was sent to Eng- 
land more than a hundred years ago, it appears to be still rare in 
American and European gardens. Philadelphus pubescens, perhaps bet- 
ter known in gardens as P. latifolius and P. grandijiorus, grows in the 
same region. as P. inodorus', they are larger plants sometimes twenty feet 
tall with stout erect stems and branches, and broad dark green leaves. 
Philadelphus pubescens, P. grandijiorus and some of their hybrids are 
common garden plants in this country. The most important and dis- 
tinct of these hybrids is Philadelphus splendens which appeared in the 
Arboretum several years ago, and its parents are believed to be P. 
grandijiorus and P. Gordonianus. It is a tall, broad, shapely shrub 
with pure white, slightly fragrant flowers borne in clusters and an inch 
and three-quarters in diameter. This plant when in bloom makes a more 
conspicuous display than any Philadelphus in the collection. The Rocky 
Mountain P. microphyllus is far removed in general aspect from the 
Appalachian species for it has the smallest leaves and flowers of any 
plant in this group. It is a shrub with slender stems, and here in 
the Arboretum has not grown more than three feet tall; perfectly 
hardy for many years, it has suffered considerably in the two cold win- 
ters of recent years. The Arboretum plants are, however, recovering. 
For a long distance the air is filled with the perfume of the flowers of 
this little shrub, which is stronger and more aromatic than that of any 
other Philadelphus. 
Perhaps the handsomest and certainly the most distinct of the Asiatic 
species is Philadelphus purpurascens, one of Wilson’s discoveries in 
western China. It is a vigorous shrub, with long arching branches 
from which spring numerous laterals from four to six inches in length; 
these branchlets spread at right angles to the stem and on these the 
fragrant flowers are pendent on drooping stalks. The bright purple 
calyx of the flowers makes a handsome contrast with the pure white 
petals which do not spread as in most species but form a bell-shaped 
corolla. One of the handsomest of the shrubs recently introduced from 
