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and very rough on the upper surface, and covered below with soft pale 
down; their petioles are not more than one-eighth of an inch long. 
This Elm can also be distinguished by the fact that the seeds of the 
fruit are in the middle of the surrounding wings. This tree does not 
produce suckers, but great crops of seeds which are blown about and 
germinate freely, and in this country produce innumerable plants 
which often become troublesome weeds. In eastern Massachusetts in 
recent years the leaves of this species and its varieties have been in- 
jured in early summer by the larvae of a leaf-mining insect which 
feed under the epidermis. Ulmus glabra, which owes its name to the 
smoothness of the pale branches, is a native of northern England and 
Scotland, and is widely distributed through Europe to the Caucasus, 
appearing again in eastern Siberia, Manchuria, northern Japan, and in 
northern and western China (var. heterophylla). Many seedling forms 
of Ulmus glabra are in cultivation. The best known, perhaps, is the 
Camperdown Elm (var. pendula Camper dotvnii). This has pendulous 
branches and branchlets which when grafted on a tall stem form a 
natural arbor. A handsomer weeping form is the var. pendula, often 
found in collections under the name of var. horizontalis. The Exeter 
Elm (var. fastigiata) is a narrow pyramidal tree with erect growing 
branches and branchlets. Var. crispa is a small tree with narrow’, 
wrinkled, laciniate leaves and is more curious than beautiful. Var. 
atropurpurea has dax*k purple folded leaves and has little to recom- 
mend it as an ornamental tree. 
Ulmus laevis. This is the common Elm in some parts of Scandina- 
via, northern Russia, and occurs sparingly in Denmark and the Balkan 
States. This tree is very closely related to Ulmus americana but dif- 
fers from it in the much thicker coating of down on the lower surface 
of the leaves and in the longer and sharp-pointed buds. The Arboretum 
specimen has been growing here since 1888, and although unfortunately 
a grafted plant is one of the handsomest Elms in the collection, now 
about fifty feet tall with a short trunk eighteen inches in diameter, 
a broad pyramidal head, and dark thick foliage. This tree is probably 
exceedingly rare in American collections. It might well be generally 
introduced into this country as it would certainly be hardy in any of 
the northern states and in Canada. It is sometimes called Ulmus 
pedunculata and U. effusa. 
Ulmus minor. This is a small-leaved Elm which is common in the 
eastern counties of England and has been reported from western Eu- 
rope. It is a tree from forty to ninety feet tall with short ascending 
branches and pendulous branchlets, and produces suckers freely. It is 
often called Ulmus sativa. There are only young grafted plants in 
the Arboretum. 
Hybrid Elms. A number of natural hybrids between Ulmus glabra 
and U. nitens have appeared in Europe. The oldest general name for 
these hybrids is Ulmus hollandica, and under existing rules of nomen- 
clature the different hybrids of the same parentage are considered va- 
rieties. The best known of these trees in the United States is the 
Huntington Elm. 
Ulmus hollandica, var. vegeta. This tree, which was raised in a 
nursery at Huntington about the middle of the eighteenth century, 
