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beauty than the fields of the plains ; one gathers 

 there great globe flowers, narcissus, columbine, 

 arnica, graceful lilies, tall gentians, and many 

 others. The mosses climb even higher than any 

 flowering plants, and the lichens seem to know no 

 limit beyond which they cannot pass, living on 

 the rocks of the highest peaks. 



To understand the cause of the characteristic 

 habits and form of Alpine plants, we must enter 

 somewhat into the conditions in which they grow. 

 In the high Alps there are scarcely four months of 

 the year when growth is possible, and even then 

 often in a temperature only ranging from o degree 

 to 2 degrees Cent. This temperature is attained at 

 noon on 96 to 120 days ; in the morning it is reached 

 only on twenty-three days, and towards evening 

 on no more than fifteen. Is it to be wondered at 

 that these little plants have diverged in habits 

 from those of the woods and plains to suit these 

 hard conditions ? The cells of their leaves are 

 smaller, the contents more concentrated, their par- 

 titions thicker than in the lowland forms, so that 

 in freezing and thawing the tissues do not tear. 

 The nightly frosts explain the low-growing habit : 

 plants are supposed to grow more rapidly by night 

 than by day. Here there can be no question of 

 growth by night on account of the frost, and as 

 they can only grow by day, the shortness of their 

 internodes is explained. For this same reason 

 Alpine plants change much on being transplanted 

 to the plains. They must needs flower quickly to 

 win time to ripen their seeds, if indeed they can do 

 so. Many instances are known of species higher 

 up flowering earlier than those lower down : Gnaph- 

 alium Hokum and Diauthus superbus flower a month 

 earlier at their highest than at their lowest limits. 

 Strong sunlight, damp mists and frequent rains 

 make up the summer climate at high levels, and 

 they force on the early flowering at the expense of 

 the accumulations stored up by the previous year's 

 growth. Intensity of light and heat are not detri- 

 mental as long as the ground remains constantly 

 saturated ; but as a protection from the power 

 of the sun's rays, the leaves are thick with 

 a very solid epidermis. They are also pre- 

 vented from drying by a pubescence of star- 

 shaped hairs ; this is quite special among the 

 crucifers, whose epidermis is generally so delicate. 

 Greyish-looking thick felt covers other plants 

 for the same purpose, especially composites. The 

 peculiarities become more marked in places ex- 

 posed to the sun and on steep slopes, than in shady 

 ravines, — edelweiss, artemisias, and Senecio are 

 examples. If we examine a Soldanella or Anemone 

 vernalis at the approach of winter we shall find in 

 the centre of the rosette of leaves, well hidden 

 away in the heart of the plant, the buds which will 

 flower in the spring. When the snow comes they 

 are fully formed, and they have not to suffer such 



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changes of temperature as do the plants of lower 

 zones, for they remain covered with snow during 

 the whole time that snow lasts. Some of the 

 early flowering species do not even wait for the 

 complete disappearance of the snow to develop 

 further ; they emerge as soon as the frozen 

 covering becomes soft enough for them to pierce 

 it. In many species the leaves resist almost 

 entirely the winter cold, and continue under the 

 snow to amass in their tissues the substances 

 which nourish the flowers in the spring. Kerner 

 observes that the leaves of Soldanella remain 

 healthy and vigorous until the birth of new stems, 

 and that then only they wither and fall. The 

 stiff, persistent leaves of small species of gentians, 

 saxifrages and azaleas play the same part. 

 Then, in the spring, when the surface of the 

 ground is soaked with melting snows, the younger 

 parts start into growth at the expense of the 

 plastic material of the older parts which have 

 ceased to grow, the older parts serving as 

 reservoirs of nutriment for the younger. I know 

 of no prettier sight than the purple bells of 

 Soldanella alpina standing in the centre of the 

 little hole which the stem has made for itself in 

 the snow. The heat that it gives out in transpira- 

 tion is enough to melt these little holes in the 

 already half-melted snow above it, and through 

 which the flower-stalk then emerges, bearing one, 

 two, or three fringed bells, developing still out of 

 the nutriment stored up in the last year's leathery 

 leaves. The flowers are over in a few days, almost 

 before the snow is gone. The auricula is another 

 very early plant that seems quite like a product of 

 the snow. 



That Alpine plants are often not able to ripen 

 their seeds seems to prove that they are placed 

 upon the limits of conditions necessary for exist- 

 ence ; but want of seed is often balanced by the 

 number of branches and buds. Their tendency to 

 form cushions and mats is also a compensation for 

 the rarity of ripe fruit. Some of them, too, enjoy 

 a very long life. Mr. Correvon, of Geneva, has 

 gathered specimens of Saxifraga oppositifolia, which 

 he judged to be at least one hundred years old. 

 This plant, therefore, might maintain itself well by 

 only occasionally ripening seed. It cannot be doubted 

 that the brilliant colours of the corollas of the higher 

 Alps have a close relation to the small number of 

 insects there to effect fertilisation by their contact. 

 Below, where flying insect wings abound, there is not 

 the same necessity for the corollas to strike the eye. 

 Hence it arises that, in the Alpine flora, the corolla 

 is not reduced in proportion to the rest of the 

 plant, for if it were so, fertilisation would be too 

 much compromised. It has been suggested that 

 the flowers have produced their special brilliance 

 and form for the purpose of attracting butterflies. 

 The bees, the great flower fertilisers of the lower 



