128 Keegan: The Bursting of the Buds in Spring. 
numerous ‘trees assume entirely a red appearance % the red 
colouration of the freshly developing twigs: the colour is so 
intense that the landscape acquires thereby a eels coloura- 
tion.’ It will only be necessary to offer a few remarks relative 
to the similar or analogous phenomena presented by our forest 
trees. A cross section through the winter buds revealed the 
presence of tannin in all cases under the form of a hyaline, 
strongly opalescent, and refractive mass occupying a great 
portion of the mesophyll and the vascular sheaths as well as the 
epidermis in beech, oak, hazel, rose, etc.; in the epidermis and 
sub-epidermis of elm, chestnut, walnut, elder, hawthorn, wild 
cherry, sycamore, and horse-chestnut; while in poplars and 
willows it is chiefly sub-epidermal. Some of the leaflets just 
bursting from the buds and the young shoots as well assume 
a decidedly brilliant and beautiful rosy flush of colour, while 
others, such as those of the horse-chestnut and lilac, are only 
feebly, or not at all reddened under precisely similar circum- 
stances. It is in the unfolding leaflets of the oak, chestnut, 
walnut, and of certain species of poplar, willow, and maple, that 
the very pretty pinkish or crimson colouration is most eminently 
exhibited. The young shoots, leaf-scales, or leaf-stalks of 
beech, lime, sycamore, aspen, field maple, etc., are much given 
to blushing very deeply and conspicuously just when, instinct 
with the fresh vitality of the bursting season, they newly enter 
into life. The case of our common beech is especially remark- 
able. No sooner has its young shoot broken through the bud 
than it is immediately coloured red, the leaf-scales which do not 
fall off are also capped with red on their upper surface, while 
a little later the stalks of the tiny leaflets join in the general 
blushing, especially on the side facing the light; and all this 
while the baby leaflets themselves burst forth as clearest emeralds. 
Now, what do those leaflets contain which are specially dis- _ 
tinguished for a pinky red, as contrasted with those which are 
brightly, brilliantly, perfectly pure green? Thus, as has been ~ 
remarked about the oak, ‘a constant succession of pink and 
brown-tinted glories of the young — is kept up in our 
moist summers til] Jate in the autumn.’ These Sgnnicee! roseate 
organisms contain apparently all along and from the first 
moment of their existence a certain quantity of sae chro=' . 
mogen ready formed ; = other leaflets contain merely the — 
tannoid quercetin, or one of its allies, whose presence may 
possibly influence to sine extent the tint of its infantile 
drapery. The deep brown of the opening cherry, etc., leaf is 
due apparently to a decomposition product of albumen called 
tyrosine. ; 
ma 
“Nata uralist, i 
