55 
exception of those in the tufts in the axils of the veins below. This tree, 
which is not rare in the northern and middle states, is one of the best 
trees to shade the streets of northern cities. The largest and handsom- 
est Linden-trees in the neighborhood of Boston are of this hybrid. 
The two Lindens of eastern Europe, T. tomentosa and T. petiolaris, 
are distinct and handsome trees with leaves silvery white on the lower 
surface, and can be easily and successfully grown in southern New 
England. T. tomentosa, which is common in the forests of Hungary, 
in this country forms a broad, compact, round-topped head with erect 
branches and large leaves erect on short stalks. T. petiolaris is a 
more beautiful tree with pendulous branches which form a narrow head 
and leaves drooping on long slender stems. It has proved to be one of 
the handsomest exotic trees which can be planted in the eastern states. 
It is occasionally seen in the neighborhood of Boston, but it is more 
common southward, especially in Newport, Rhode Island, where there 
are a number of noble specimens. 
It is too soon to speak with much knowledge of the value of the Asi- 
atic species as ornamental trees in this climate. Most of them have been 
introduced in recent years, and the oldest Asiatic Linden now in the Ar- 
boretum, Tilia japonica, was raised here from seed only planted in 1893. 
A comparatively large tree in Japan, the Arboretum species are now from 
twenty to twenty-five feet high, and are attractive trees with gracefully 
drooping branches and open habit. The leaves unfold earlier in the spring 
than those of any other Linden in the collection, and are small, cordate 
at base and pale on the lower surface, like those of the small-leaved 
European Linden {T. cordata) to which the Japanese tree bears some 
resemblance. The Arboretum trees have now flowered every season 
for several years, and the flowers are large, bright yellow, and like 
those of other Lindens, very fragrant. For its flowers, which appear 
when few trees bloom in this climate and are beautiful and conspicu- 
ous, this Linden should be better known. An earlier Asiatic Linden to 
reach the Arboretum, where it was first raised in 1883, was the north 
China T. mongoLica. This was a small tree, at least in this country, 
with small, nearly triangular, lustrous leaves. When only a few years 
old it began to flower and produce fertile seeds. It proved, however, 
to be short-lived here and soon disappeared, to be replaced by what are 
still young plants of a later generation or of different introduction. All 
the other Asiatic species are or have been in the collection at different 
times. They are all hardy enough, but at best grow slowly, and ap- 
pear to lack vigor of constitution. Of the species lately introduced T. 
Oliveri now appears the most promising. 
Hybrid Lindens. As in many other genera of plants, the union of 
two species has produced Lindens superior to the parents. As has 
already been stated, Tilia vulgaris, which is believed to be a natural 
hybrid, is a better tree, at least in this country, than either of the par- 
ents. The Crimean Tilia euchora, with dark green, lustrous leaves, is 
believed to be a natural hybrid between T. caucasica and T. cordata. 
This handsome tree is hardy in the Arboretum but does not grow as 
well here as in western Europe where it is often recommended as a 
street tree. One of the handsomest Linden-trees in the Arboretum 
collection, T. spectabilis, is believed to be a hybrid of T. glabra and 
