524 THE BOTANICAL EXCHANGE CLUB OF THE BRITISH ISLES. 
The most remarkable of the other forms of Elm is the tree 
long and erroneously known as U. campestris. This Henry thinks is 
“ one of the descendants of the first cross between the above species, 
and possibly due to a second hybridisation of some of these de- 
scendants with U. mo?iiana. The Huntingdon Elm {U. vegeta) he 
looks upon as a first cross of U. mottiana x glabra. It originated 
as a seedling at Huntingdon 1746 — 1756- It is glabra than 
montana ; there is no pubescence on the upper surface of the leaves, 
which are long stalked, but they are as thick as in montana ; the 
branchlets are shorter and often do not become striated. The 
samarae are intermediate. It suckers freely, and produces an abund- 
ance of fertile seeds, and is a very vigorous grower. The suberosity 
of Elms is of no varietal value. The seedling of U. montana has 
an unbranched stem drooping to one side with large leaves, only 
the first two of which are opposite. The seedling of U. glabra has 
a stiff unbranched erect stem, with all the leaves small in size and 
in opposite pairs. The result of cultivation of the Huntingdon 
seedlings closely follows the Mendelian ratio, eight different kinds 
being obtained. 
The English Elm is usually barren. Henry’s results induce 
him to believe that in Britain we have only two species, the other 
Elms being hybrids of these species. 
With Poplars he gives the following interesting suggestions : — 
P. nigra., L. The European Black Poplar which has long been 
in cultivation — Leaf: non-ciliate in margin; without glands at the 
base ; cuneate at the base ; long acuminate at apex. [Leaves of 
this were distributed by me from Christ Church Meadow, Oxford. 
See Rep. 309, 1907.] 
P. deltoidea, Marsh. (North America.) Leaf : densely ciliate 
in margin ; with two glands at the base on the upper surface ; 
truncate at the base ; cuspidate at the apex. 
Soon after the American species was introduced in the 
eighteenth century into France, a first cross acciilentally arose, 
which became known in France as P. nigra hclvctica, and when im- 
ported into England was called the Black Italian Poplar. The 
single tree (male) has always been reproduced by cuttings. It is 
a most vigorous grower (characteristic of first crosses), amply distinct 
from either [larent not only by its rapid growth but by its habit, 
slender ascending Inanches and straight cylindrical stem. He 
