1899] PPE FLORA OF THE ALPS ITI 
bright colour of flowers is to attract insects. We find it in flowering 
plants where it can have no such function, as in the scarlet stigmas of 
the hazel, which is unquestionably anemophilous, and in the young 
inflorescence of the larch; or, in Cryptogams, more especially in con- 
nection with the organs of reproduction, as in the brightly-coloured 
oogones and antherids of Chara and the red sporanges of Sphagnum. 
There can be little doubt that the bright red colour has an important 
function in absorbing and retaining the heat-rays, and thus maintain- 
ing the organ at a temperature necessary for the physiological processes 
going on within it. Hence the very earliest of the flowers of the 
Alps, like Soldanellas and Hepaticas, are usually very brightly coloured, 
and the earliest spring foliage has also very commonly a more or less 
bright red tint. 
There are other and equally interesting characteristics of alpine 
plants. And here it may be worth while to contrast the conditions of 
life in high altitudes and in high latitudes, which are often assumed 
to be very similar. They are, in truth, totally different. In the 
arctic or subarctic zone we have a brief summer, during which there is 
almost perpetual insolation and a nearly uniform temperature through- 
out the twenty-four hours; in Switzerland the summer nights are 
longer than they are with us, and the difference of temperature between 
day and night is often excessive, the nights being associated, even in 
the height of summer, with exceptionally heavy dews. It will be 
seen, therefore, that we have totally different climatic conditions to 
deal with. We have in our own flora several arctic species which do 
not occur in Switzerland, as, for example, Saxifraga nivalis and Primula 
scotica. 
Alpine plants have several other characteristics besides the large 
size or close crowding of the flowers. In the first place, although 
many ripen abundance of seed, but a very small proportion, as has 
already been mentioned, are annual. In many the floral organs are 
almost completely formed within the flower-bud during the preceding 
autumn, so that they are ready to unfold with the first warm days of 
spring, and before the appearance of the leaves, not requiring these 
organs to supply them with any further food-material. Hence the 
very early flowering of many alpine and sub-alpine plants, such as 
the hepatica, Christmas rose, winter aconite, species of Soldanella, 
Primula, Gentiana, etc. Secondly, from the great strain to which 
they are subject from violent winds, we find a considerable number 
with prostrate woody stems, species of willow, birch, etc., such as we 
seldom meet with in plants of our own climate. For the same reason 
the root-system is also often very strongly developed in comparison 
with the aerial part of the plant. Furthermore, the extreme bright- 
ness of the sun during the summer months has a tendency to cause 
excessive transpiration or evaporation from the leaves, which has to be 
counteracted by specialities of structure. This protection is afforded 
