TREES OF THE CAMBRIDGE BOTANIC GARDEN. 



17 



fruits are rather larger and more markedly obovate. It is found in 

 the hedgerows and park lands of Essex, Cambridgeshire, Huntingdon- 

 shire, and elsewhere. The slide exhibited was from a photograph taken 

 in the grounds of St. John's College, Cambridge. 



45. U. stricta Lindley (Moss in Gard. Chron. ser. 3, li. 199 et 

 234 (1912) ; Cambridge British Flora, ii. 92, tab. 98, 99). 



This is the Cornish Elm, well known and useful for planting on 

 account of its upright pyramidal habit. It comes true from seed, and 

 it is stated by Elwes to be undoubtedly indigenous in Cornwall, and 

 he believes it to be, in all probability, a pure species. It occurs abun- 

 dantly in hedgerows and on the borders of woods in western Cornwall 

 and northern Devonshire. It also occurs rarely throughout southern 

 England, and it is reported by Professor Henry to occur in southern 

 Ireland. Abroad it can be recorded only for northern France. In 

 Cornwall the tree is of slow growth, but produces a remarkably tough 

 wood used by wheelwrights and formerly used to make the casks in 

 which cement and china clay were exported. It has been used also 

 for making boxes in which gunpowder was compressed by hydraulic 

 power, no other wood being found to bear the pressure so well. The 

 leaf -blades are described as not very unequal, smaller than in U. nitens. 

 The fruit is the same as in that species. The only tree likely to be 

 confused with this is the Jersey Elm, U. stricta var. sarniensis Moss 

 (Gard. Chron. li. 199 (1912)). It differs from the Cornish Elm in 

 flowering earlier, in its branches ascending at a rather wider angle, 

 and in its broader laminae, which are quite flat and not folded inwards. 

 It is perhaps a hybrid between U. stricta and U. nitens. 



46. U. sativa Miller (Gard. Diet. ed. 8, No. 3 (1768) ; Moss in Gard. 

 Chron. ser. 3, li. 199 et 216 (1912) ; Smith, Eng. Bot. t. 1886, in ed. 3 as 

 U. suberosa var. genuina ; Cambridge British Flora, ii. 93, t. 100, 101). 



This is the Small-leaved Elm, a tree readily recognized by its habit 

 and small leaves. It is distinctly an ornamental tree. The branches 

 are rather short, lower ones wide-spreading ; the leaf-blades are not 

 very unequal at the base, smaller than in U. nitens ; the fruit is smaller 

 than in U. nitens, oblong-elliptical to obovate. The winter-buds are 

 smaller than those of any other British Elm. The timber of this tree 

 is said to be of excellent quality. It is found chiefly in Eastern England, 

 but is local in Southern England from Hampshire, Gloucestershire, 

 and Glamorganshire to Essex and Lincolnshire. 



47. U. campestris L. (Sp. PI. 225 (1753) partim ; Moss in Gard. 

 Chron. ser. 3, li. 199 (1-12) ; The Cambridge British Flora, ii. 94, 

 t. 102, 103). 



This is the English Elm, one of the tallest of British trees,* attaining 

 a height of about 130 ft. It is a tree that confers a distinction upon 

 Cambridge, forming as it does the feature of the well-known " Backs." 

 The trunk is long and straight, the timber reddish and reputed to be 



* The other of the two tallest trees is Populus sciotina. 



VOL. XLI. C 



