Keegan: The Chemistry of the Lakeland Trees. 183 
pigment (carotin). Secondly, the powerful chromogens which 
tannic and phenolic bodies and their derivatives. 
ch Elm. Ulmus montana. This is a true native and 
special characteristic of the Lakeland Forest. The chemical 
analysis does not elicit any very notable feature, save an 
except the inconvenient abundance of mucilage. in bark and 
leaves contained in the cavities of special mucilage-containing 
sacs. The bark contains a tannin which exhibits reactions and 
decomposition products, similar to that of the oak, etc. ; it also 
‘contains a small quantity of resin, but I have searched in vain 
for any definite bitter principle, and there is only a mere trace 
of free phloroglucin in the tree. The leaves have much carotin, 
which continues into the autumn, imparting the brilliant yellow 
SO conspicuously exhibited at that season; there is also a little 
tannin, and a soluble yellow colouring matter which is not rutin 
or quercetin; also sugar, quinic acid, much wax, but only a small 
quantity of starch, and probably mannite. 
irch. Betula alba. This, ‘the queen of the woods,’ is 
fitly represented in the district, and it contributes by its silvery 
bark, the lightness of its graceful outline, and the feathery 
evolution of its foliage to invest many a sylvan bank, steeply 
acclivitous ledge, pastoral hollow, or fell rising into mountain 
solitude with features of lasting beauty and picturesqueness. 
It is one of our few trees that ‘bleed’ copiously in the early 
months of the year, and the sap thus exuded is mainly a solution 
of sugar (levulose with some dextrose) with salts of potass and 
contains about 34 Bt cent. of a white resin called betulin, 
C*H®O*, also about.5%4 per cent. tannin, which exists in little 
globules of solution encased in a film of albuminous matter, and 
is iron-blueing and yields on boiling with dilute HCl a red-brown 
phlobaphene and glucose, there is also a bitter principle, quinic 
acid, and some free phlobaphene, but no phloroglucin. Not- 
withstanding the prevailing clear colouring and the delicate 
flexibility of the leaves, they are extremely rich in chemical 
constituents; in the young state they contain about 4% per 
cent. nitrogenous matters, later on there is much wax, Carotin, 
0°3 per cent. essential oil with two resin acids (secreted by the 
June 1898. : 
