Sunshine, Rain, and Wind 
the character of flowering plants, and even to give some 
species a distinct advantage over others. 
Along railway lines in Southern Sweden the flowers 
on the north side of the line (with a southern exposure) 
will be chiefly Barbarea vulgaris, Convolvulus arvensis, 
Anthemis tinctoria, and -Alyssum calycinum, and there 
is no close carpet of mosses but only small tufts 
of Ceratodon, Tortula ruralis, and Funaria. But on 
the south side (with a northern exposure) there is 
a close moss carpet (Hylocomium), and the common 
plants are buttercups (R. acris), grasses such as Aira 
czspitosa and Cerefolium silvestre.” 
There is a peculiar reddish colour which the reader 
must have noticed on plants growing in very exposed 
places, and which is due to a special substance called 
anthocyan. This colour seems to be directly produced 
by the effect of certain kinds of sunlight (the violet and 
ultra violet rays), But when once formed it protects 
certain valuable ferments or enzymes, such as diastase 
(which changes starch into sugar), from being destroyed 
by those same violet rays. So that in anthocyan the 
evil itself seems to have produced exactly what is 
required in the way of a remedy.”° 
Sunshine also helps to produce such substances as 
carotin, which are found in flowers,”! and as we have 
seen intensifies not only flower colours but also perfumes. 
Nor is it only colour that is affected but also the number 
of stamens. In warm places it has been found that the 
chickweed has more stamens than elsewhere. On such 
a plant as the‘common Bocconia the number both of 
stamens and carpels is always greater in those flowers 
that are well placed as regards light and which are well 
supplied with nourishment.” This effect of nourishment 
and more genial conditions generally is also very well 
seen in poppies (P. Rhoeas) and marsh marigolds, As 
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