254 



SCIENCE-GOSSIP. 



delicate intermingling of the two rocks has gone on 

 along them. The eurite has melted up the easily 

 fusible andesite, and, in turn, the melted andesite 

 has attacked its invader. Consequently crystals of 

 quartz and flesh-red felspar, derived from the 

 eurite, are found floated away some inches into the 

 marginal andesite, and at first sight it would 



appear as if the andesite were the later rock. The 

 microscope, applied to thin sections, shows how 

 intimate a mixture of the two materials has 

 occurred, A foot away, however, from the planes 

 of junction, the andesite contains only its original 

 and proper crystals. 



Royal College of Science for Ireland, Dublin ; Dec, 1895. 



ALPINE PLANTS, 



By Sophia Armitt. 



IMMEDIATELY below the lines of perpetual 

 snow is the home of the Alpine flowers ; we 

 can hardly fix a limit to the height at which they 

 grow, for the snow-line varies, lifting itself higher 

 the nearer one approaches the equator. In the 

 region below the snow, above the trees, of which 

 the last are pines and elders, the Alpine herbs 

 occupy the ground alone, spreading themselves 

 out in mat-like and characteristic fashion. Not 

 that there are no trees here, but only the initiated 

 know how to find them ; they have had to accom- 

 modate themselves to hard conditions, to such 

 protection in winter by burying their stems in 

 earth, or to creep in tortuous zigzags between 

 crag and boulder. The little herbaceous willow, 

 Salix herbacea, lives on some of the wind-swept tops 

 of our English mountains; it has a little woody 

 trunk underground, quite thick and hard, sending 

 forth in summer short-lived herbaceous branches, 

 set with small grey leaves and single tiny catkins. 

 The netted willow, S. reticulata, is a tree too, creep- 

 ing over the surface of rocks and stones, with large 

 round net-veined leaves, and is a handsomer plant 

 than the former. Of truly woody plants, in the 

 European Alps, there are few besides the dwarf 

 willows, some rhododendrons, the beautiful moun- 

 tain heath, Erica carnea, and one single Azalea of 

 like habit with the willow, A. procumbens. These 

 are scarcely characteristic Alpines ; the willows 

 are Arctic rather than Alpine ; odd instances of 

 survival in inclement regions of such natures as 

 were plastic enough to bend before the storms of 

 winter, and the rhododendrons of Europe have, I 

 think, a lower range than the Alpine flowers. The 

 true Alpine plants are low growing perennial 

 herbs with woody roots ; annuals are rare in 

 this zone, only a few small species growing on 

 damp sand, as Gentiana tenella ; in habit they are 

 dense, growing close together in belts or masses ; 

 they have a relatively small amount of foliage to 

 their large and brilliantly-coloured flowers. No 

 lowland flowers produce such vivid colouring or 

 grow in such colonies and conspicuous patches ; 

 it is the cumulative habit, the colour of each 

 flower, thus helping the others to look attractive — 

 that is, perhaps, most characteristic. They lie 



very low in compact rosette-like masses ; they are 

 scarcely higher than the ground they decorate so 

 profusely. This close habit and profusion of 

 bloom, the very desideratum of the gardener's art, is 

 found on Alpine slopes, the product of wild nature 

 alone ; it is the product of long winters, short 

 summers, hard conditions. The coldest climates 

 produce the loveliest flowers. Many of these 

 hardy herbs yield resinous and bitter substances ; 

 these flowers secrete plentiful honey, often stored 

 in deep and open bells. All the mountain chains 

 of the world have their Alpine floras, and if they 

 are somewhat of the same character, they are also 

 each one special in possessing species not to be 

 found elsewhere. Some are richer than others, 

 but all have some peculiarity. On the mountains 

 of Oceania the genus Veronica dominates ; on the 

 Andes abound species of Pentstemon, of dwarf 

 umbellifers, of fuchsias, of gentians and saxifrages, 

 quite different from those familiar to us. The 

 North-American mountains have their phloxes and 

 Oenotheras. The Himalayas are rich in curious 

 composites and rhododendrons. The Alps of central 

 Europe, which alone are known to me, yield many 

 species of ranunculus, crucifers, saxifrages, cam- 

 panulas, phy teumas, gentians, and primulas. There 

 are some few far-reaching species that extend from 

 the Arctic Circle to the Alps of the south 

 temperate zone, They cross the tropics from 

 north to south by the only bridge there is, the 

 chain of Andes. They are but lowly little plants, 

 Epilobium alpinum, Erigeron alpinus, Empetrum 

 nigrum, Phlceum alpinium, Lycopodium selago, etc. 

 We find the characteristic Alpines of Switzerland 

 and the Tyrol on slopes from 6,000 to 9,000 feet 

 high ; some few have been found higher, Ranunculus 

 glacialis, Saxifvaga azoides, Achillea atrata have been 

 found as high as 12,000 feet ; but one may revel in 

 Alpine flowers from about 7,000 feet to the glacier 

 edges and the snow level, culling a rich harvest in 

 a short summer. One happy year that I spent in 

 those valleys I got five hundred species, and four to six 

 specimens of each. So rich did I find the Engadin 

 that the necessary time for pressing the plants was 

 almost more than I had patience for. Lower 

 down, the valleys themselves seem richer in floral 



