XLIX.— ' THE WYCH-ELM. 
Ulmus glabra Hudson. 
T HE fifth Order of Dicotyledons is the Urticales , a very varied group of plants, 
the mutual relationship of which is somewhat doubtful in so far that their floral 
structures are of a reduced simple character, whilst they differ somewhat widely in 
such other characters as habit, latex, or milky juice, position and bending of the 
ovule, etc. They seem, however, to agree in having small green flowers arranged 
cymosely, their parts in whorls and usually dimerous, the stamens superposed to the 
perianth-leaves, and the ovary superior and uniovulate, forming an indehiscent achene 
or nut. The Order comprises three Families, the U/mace<e, Morace<e , and Urticace 
having between them 109 genera and about 1,400 species. 
The Family Ulmacea is a considerable group of trees and shrubs, mostly 
belonging to Northern Temperate regions, with a watery juice ; distichous, 
simple, pinnately-veined, and often oblique, stipulate leaves ; and perfect flowers with 
sepaloid persistent perianth and two united carpels, producing a solitary, pendulous, 
anatropous ovule, which becomes an exalbuminous seed with a straight embryo. 
The genus Ulmus comprises some sixteen species, with mucilaginous, bitter, and 
astringent bark ; rough foliage, with caducous stipules ; flowers in small clusters, 
sessile on the sides of the twigs ; and a flat ovoid samara or winged fruit, the wing 
in this case practically surrounding the seed-cavity. The flowers appear before the 
leaves and are each of them solitary in the axil of one of the clustered bracts. 
As in many wind-pollinated plants, the flowers are protogynous, the stigmas 
remaining receptive for a long time ; and the filaments double in length just before 
the bursting of their anthers. Fertilisation is chalazogamic, and the samaroid fruit is 
obviously adapted to dispersal by wind. 
The forms of Elm found growing in the hedgerows of southern England have 
been the despair of most botanists who have attempted to discriminate between them. 
Some striking characters have been found not to be constant even on two parts of 
the same tree. Such are the presence or absence of projecting ridges or “ wings ” of 
cork on the twigs, the size and form of the leaf, and the number of perianth-segments 
and stamens, numbers which vary together from four to five. On the other hand, 
there are characters which seem more constant and, therefore, more useful in the 
discrimination of species. These are the production or non-production of suckers ; 
the shape of the fully-formed samara, whether obovate or sub-orbicular ; the position 
of the seed-cavity or loculus with reference to the notch or sinus between the two apices 
of the wing, at the summit of the fruit, it being in some cases central and in others 
nearer to the sinus ; and lastly the production or non-production of fertile seed. 
From these characters and the less easily defined general habit or growth-form 
botanists have generally recognised two main groups of Elms in England and have 
thought that in so doing they were following the ancient Greek botanists and Linnaeus. 
