39 
than of any other Elm, The well-known Camperdown Elm is a form 
of this tree with regularly pendulous branches which is often planted 
in suburban gardens to make natural arbors; another form (var. pen- 
dida) has horizontally spreading pendulous branches which form an 
unsymmetrical, flat-topped head. There is a form with erect branches 
forming a narrow pyramidal head and others with leaves more coarsely 
toothed than those of the ordinary form and with purple and other 
abnormal leaves. This is perhaps the least beautiful of all the species 
of Elms. The abundant seeds are blown great distances and germinate 
80 readily that seedlings are often troublesome weeds which if neg- 
lected for a few years become difficult to eradicate. For several years 
the leaves of this tree in the neighborhood of Boston have been turned 
brown and often killed by a leaf-mining insect which attacks this spe- 
cies but no other Elm-tree. 
Ulmus minor, sometimes called U. sativa, is a small-leaved Elm-tree 
of large size which is rather closely related to U. foliaceu. Although 
common in the eastern counties of England, it is possible that this 
tree cannot be seen in the United States outside of the Arboretum. 
Ulmus hollandica. This general name has been given to a race of 
natural hybrids betv/een U. foliacea and U. glabra, among which are 
.some of the handsomest and most valuable of the European Elms. To 
the best known in this country of these hybrids the name Ulmus hol- 
lamdica vegeta has been given. This tree was raised in a nursery at 
Huntingdon about the middle of the eighteenth century and is usually 
called the Huntingdon Elm. This tree often grows one hundred feet 
high with a massive trunk and spreading and ascending branches which 
make a vase-shaped head which readily distinguishes this tree from 
other Elms. It can be seen to good advantage in Cambridgeshire, 
England, especially in Cambridge, where there is a noble avenue of 
the Huntingdon Elm. A tree of this hybrid which grew in the grounds 
of Magdalen College at Oxford was believed to be the largest tree in 
Great Britain, In April, 1911, this tree was blown down and was 
found to be one hundred and forty-two feet high v/ith a trunk twenty- 
seven feet in circumference at five feet above the ground. In this 
country this hybrid Elm grows more rapidly than other Elm-trees, and as 
it produces suckers it can be easily multiplied. It is not common here, 
however, although in the neighborhood of Boston specimens not more 
than sixty years old have already grown to a large size. The var. 
belgica of this hybrid is the Elm which has been most often planted as 
a street and roadside tree in Belgium and Holland. It is a tall tree 
with a straight, rough-barked trunk, a broad head of rather erect 
branches, and dark green leaves slightly roughened above and cov- 
ered below with soft down. As this tree grows in Holland it is one 
of the handsomest and most desirable trees for shading city streets. 
This Elm appears to be little known in the United States; it is grow- 
ing well in the Arboretum, but it has not been here long enough yet 
to show if it will be of permanent value in New England. The so- 
called Dutch Elm, Ulmus major of many English dendrologists and a 
common tree in English parks, is probably another hybrid of the same 
parentage (U. hollandica var. major). This is a very large tree with 
