We are told by Sir Archibald Geikie (p. 851) that "from the Pyrenees eastwards, through the Alps and Apennines into Greece, and the southern side of the Mediterranean basin, through the Carpathian Mountains and the Balkan into Asia Minor, and thence through Persia and the heart of Asia to the shores of China and Japan, a series of massive limestones has been traced, which, from the abundance of their characteristic foraminifera, have been called the Nummulitic Limestone. Unlike the thin, soft, modern-looking, undisturbed beds of the Anglo-Parisian area, these limestones attain a depth of sometimes several thousand feet of hard, compact, sometimes crystalline rock, passing even into marble, and they have been folded and fractured on such a colossal scale that their strata have been heaved up into lofty mountain crests sometimes 10,000, and in the Himalaya range more than 16,000 feet above the sea." "Nowhere in Europe," continues the same author (p. 860), "do oligocene strata play so important a part in the scenery of the land, or present on the whole so interesting and full a picture of the state of Europe when they were deposited, as in Switzerland. Rising into massive mountains, as in the well-known Rigi and Rossberg, they attain a thickness of more than 6000 feet." "By far the larger portion of these strata is of lacustrine origin. They must have been formed in a large lake, the area of which probably underwent gradual subsidence during the period of deposition, until in Miocene times the sea once more overflowed the area."

From these remarks by our most eminent British geologist, we gather that in early Tertiary times much of the present area of Switzerland was either a sea or a large freshwater lake. The Alps were then appearing in this sea, probably as a chain of islands, and in the beginning of the Miocene Epoch one large elongated island had made its appearance—the future European Alps. I have already mentioned that the Miocene Sea skirted the Alps from the Mediterranean up the valley of the Rhone and along its northern and eastern margin. Miocene marine deposits are also known from the Southern Alps and the east side of the Apennines, from Corsica, Sardinia, and Malta. No trace, however, of them has been noticed anywhere along the Ægean Sea or on the Balkan peninsula. The Alps were therefore connected to the east with the outliers of the Balkan Mountains, and in this way with Asia, from which they received so large a proportion of their fauna and flora. In pliocene times the sea still washed the southern shore of the Alps, but to the north dry land gradually supplemented the sea, and the Alpine fauna and flora were able to pour into the plain. It was then that the Arctic species—which we have learned had migrated into Northern Europe from the north—found their way to the Alps. In a similar way Lusitanian forms—in fact, species from almost all parts of Europe—were now free to wander to the newly opened up peninsula which had become part of the mainland of Europe. The typical Siberian species had not entered our continent at that time, it was not till much later—not until the middle of the Pleistocene Epoch—that they made their appearance at the foot of the Alps, but, as we shall see later on, it is doubtful whether many of these species ever reached the mountains.

The fauna of the Alps, and also the flora, is therefore made up of a number of component elements. In the first place we have the Oriental element—the migrants from Central and Southern Asia. When the nature and origin of the Oriental fauna in Europe was discussed, reference was made to the fact (p. 272) that we can distinguish an older from a newer Oriental migration. Both of these have entered the Alps. As we might anticipate, many of the older Oriental migrants have developed into new species, laying the foundation of an indigenous Alpine element. From the fact that they set foot on the Alpine peninsula, it might be expected that there could have existed no mountains to speak of. The climate was mild and damp. Now as the country rose, and a formidable mountain range took the place of a hilly island, the whole fauna was lifted up and transferred to entirely different conditions. A modification of their structure to suit the new surroundings was therefore to be anticipated, and that is exactly what occurred, though not in all cases.

Take, for example, the goats which are of Asiatic origin. Every one has heard of the "Steinbock,"—the Alpine mountain goat (Capra ibex)—though very few have seen it in its native haunts, where it is now on the verge of extinction. A closely allied species (Capra sibirica) inhabits the AltaÏ and Himalayan Mountains; a third species (Capra sinaitica) lives in Palestine, and has entered Egypt by way of the Sinaitic peninsula. Another (C. Ægagrus) occurs in Asia Minor, Persia, the island of Crete, and some of the Cyclades. This exemplifies what I remarked in the last chapter about the former land-connection between Greece and the Asiatic continent. Finally, we have the Pyrenean Goat (Capra pyrenaica), which is found in the Pyrenees, the higher ranges of Central Spain, in Andalusia, and Portugal, thus indicating that it probably reached the Spanish peninsula from the south by means of the old Sicilo-Algerian highway, especially as remains of the species occur in the cave deposits of Gibraltar. The ancestors of the goat-like Antelope—known as the Chamois (Rupicapra tragus)—no doubt also came from Asia. The genus is not represented there, but Nemorhoedus and Budorcas are allied Asiatic genera, while the Rocky Mountain Goat (Haploceros montanus) also has certain affinities with the Chamois. Besides the Alps, the latter occurs in the Caucasus and the Pyrenees. The Alpine Marmot (Arctomys marmotta) is sometimes quoted as owing its origin to the Siberian pleistocene migration, but it does not occur in Siberia now, nor is there any palÆontological evidence that it was ever found there. The genus Arctomys is an ancient Asiatic genus, to judge from its general range. Only two species occur in Europe, one of which, the true Siberian Marmot (A. bobac), just enters our continent in the east—or rather, it is one of those species which came to us in pleistocene times and are now gradually retreating towards their native land. The genus, however, is probably not of Siberian origin. No less than seven other species occur in Asia, six of which are confined to Central Asia and the Himalayan Mountains, while four have wandered to North America. The sequence of events, therefore, was that the ancestor of Arctomys marmotta probably came to the Alps direct from Central Asia by way of Asia Minor in miocene or pliocene times. It has since become modified into a distinct species, and has spread to the European plain, where it occurs fossil in pleistocene strata, and to the Carpathian Mountains and the Pyrenees.

The great majority of species of the large genus Microtus (Arvicola) are Asiatic, and there can be little doubt that it has originated in that continent. There is one species of Vole (Microtus nivalis) which occurs in the high Alps, and which has been supposed to be a typical Alpine form. It is known, however, to occur also in North Italy and in Bohemia, while Microtus leucurus of the Pyrenees is identical with this species. But its range is by no means confined to Europe, for it has also been discovered in Syria and Palestine, while a closely allied form exists in the Himalayan Mountains. This shows clearly that the species has migrated to the Alps from Asia Minor. That this migration may have taken place at an early period—at a time when Sardinia and Corsica were still connected with Southern Europe—is indicated by the occurrence of an extinct Vole (Microtus brecciensis) in Sardinian and Corsican pleistocene (?) deposits.

All the Alpine species mentioned except the Chamois can be easily traced to their former Asiatic home. But even it has its nearest relations in Asia. I might also refer to another Vole (Evotomys Nageri) which is practically confined to the Alps and Northern Italy, and which has probably originated there, though most of its nearest relations are either Asiatic or North American species.

But besides these Asiatic immigrants and their modified descendants we have a small truly native Alpine mammalian fauna. Sorex alpinus—the Alpine Shrew—occurs only in the Alps, the Harz Mountains, Pyrenees, and Carpathians. The genus has been found in European eocene strata,—in vastly older deposits in our own continent than elsewhere,—so that it is extremely probable that it has originated there. It may then have developed a new centre of distribution in the newly-formed Alps where both Sorex alpinus and S. minutus (pygmÆus) have their home. From there they again spread—perhaps already in miocene times—to Asia and North America, where a large number of new species originated. It seems to me even probable that one of these Asiatic species of Sorex, viz. S. araneus (vulgaris), subsequently migrated towards the old home of its forefathers, since we find it more or less confined to Central and Northern Asia and Northern Europe.

Though the origin of the Alpine Hare has already been referred to and fully discussed in a previous chapter (p. 148), the conclusions arrived at may be once more repeated. The Alpine Hare (Lepus variabilis) is of Arctic origin. It spread southward into Europe, North America, and Asia in early glacial times, and reached our continent from Spitsbergen by means of a direct land-connection with Lapland. The Scandinavian peninsula was then separated from Russia, but connected with Scotland and Ireland (Fig. 13, p. 170). Since England was then united to France, the Alpine Hare was able to invade western continental Europe and all the mountain ranges. Its range is very discontinuous, small colonies being scattered all over the mountainous parts of the Northern Hemisphere, while the European Hare—a closely allied species—occurs in the plain, and now occupies to some extent the former haunts of the Alpine Hare (cf. Fig. 8, p. 137). Might not the European Hare, as suggested, possess some advantages which enabled it to drive the other into more inaccessible parts, thus producing the peculiarity of range? The present distribution of the Alpine and the European Hare (L. EuropÆus) appears to me to strongly support such an assumption. It is not the cold which has driven the Alpine Hare to the Alps; and its presence there is not, as is often supposed, a "standing testimony of a former arctic climate" in Europe, but merely the necessary consequence of the weaker species being thrust into less accessible regions by a stronger rival.

Muscardinus avellanarius,—the common Dormouse,—though by no means confined to the Alps, has probably originated there. It is found up to a height of nearly 5000 feet in these mountains, and is spread over Europe at nearly equal distances from the Alps in all directions. Being absent from Ireland, Scotland, Norway, and Northern Russia, it seems as if it had only diffused northward in more recent times.

The closely allied genus Myoxus is likewise of European extraction, some species being known from French eocene deposits.

There are only a few typically Alpine Birds. One of these is the Alpine Accentor (Accentor collaris), which on rare occasions visits England, and Northern Europe generally. It is, however, by no means peculiar to the European Alps; a variety of this species occurs in Central Asia, Eastern Siberia, and Japan. The only other Accentor inhabiting our continent is the Hedge Accentor (A. modularis), which is resident over the greater part of it, and also in North Africa and the Mediterranean Islands. It also extends its range across the Ægean Sea to Asia Minor, so that really not a single Accentor is peculiar to Europe.

Both the European species are evidently old forms, and the genus, as might be expected, is certainly Asiatic. No less than ten other species of Accentor are known, all of which are confined to Central Asia and the Himalayan Mountains, and are therefore all Holarctic. I may mention that much difference of opinion still exists as to the true zoological position of this anomalous genus. It has been located in several different families by various ornithologists, but has not yet found a permanent resting-place. Another bird generally considered to be peculiar to Switzerland is the Alpine Chough (Pyrrhocorax alpinus), but its range extends across Asia Minor to the Himalayas. Whether the European Chough should not form a distinct genus is a matter of opinion. Some of our leading ornithologists, like Dr. B. Sharpe, are inclined to separate it from Pyrrhocorax; however, there is no doubt that it is closely related to the Alpine Chough, whatever view we may take of the generic distinctness. It inhabits principally Western and Southern Europe, also North Africa; and its range extends eastward to the Himalayas, China, and Eastern Siberia. If any doubt still existed as to the Asiatic origin of the Choughs, it may be noted that the only two other closely allied genera, viz., Corcorax and Podoces, live in Australia and Central Asia respectively.

There are two other birds to which I should like to refer. These are the Rock Sparrow and the Alpine Snow Finch. The first of these (Petronia stulta) is by no means peculiar to the Alps. It is the only species of the genus inhabiting Europe; and besides the Alps it occurs in Southern Europe generally, and ranges as far west as the Canaries and Madeira. Eastward it is not found beyond Central Asia. Of the remaining five species of Petronia, two occur in Asia (including India) and three in Africa. Whether the genus is African or Asiatic is immaterial for our purpose, since, in any case, the only European species came to us from the east with the Oriental migration. The distribution of the Alpine Snow Finch (Montifringilla nivalis) is very similar to that of the birds we have just been considering. It inhabits the Alps up to a great height, but occurs also on the Pyrenees and other South European mountain ranges as far east as Palestine, where again it is found in the Lebanon. The genus Montifringilla has seventeen other species. Twelve of these live in Central Asia and Japan, extending as far north as Kamtchatka, while five inhabit Western North America right down to Mexico. There is every probability that in this case also we have to deal with an Asiatic genus which spread eastward to America, and westward to Europe.

As regards the Reptiles, there are no peculiar Alpine forms, but among the Amphibia some species deserve to be mentioned. Up to an elevation of 10,000 feet we find in the Alps the Black Salamander (Salamandra atra); and it is apparently quite peculiar to them, never having been observed in the plains. The handsome black and yellow Salamander (Salamandra maculosa)—so well known as a terrarium specimen—likewise occurs in the Alps, and it has besides a fairly wide distribution in Europe. It is known from Southern Germany, the Pyrenees, Spain, Portugal, Sardinia, Corsica, Greece, Syria, and Algiers. A third species (S. caucasica) inhabits the Caucasus. The evidence of distribution here points emphatically to an Alpine origin of the genus Salamandra. We cannot tell where the ancestors of Salamandra may have come from, but several other genera of SalamandridÆ are certainly Asiatic. Our common Newt (Molge vulgaris) belongs to a genus with nineteen species, several of which are peculiar to Europe. The general range of the genus, however, extends to North America, and it is more probable therefore that it originated in Asia. If so, it certainly must have passed into Europe at a very early date. Let us assume the first Molges to have traversed the Ægean Sea on terra firma to Greece in miocene times, they might thus have been able to travel straight on to the old Tyrrhenian continent of which Corsica and Sardinia now form the remains, and also on to North-west Africa. Indeed, we find high up in the Corsican mountains an interesting large brownish-grey Newt (Molge montana), and another in Sardinia (Molge Rusconii). Again, in Algiers there are two species, viz., Molge Poireti and M. HagenmÜlleri, while the Moroccan M. Waltlii passes into the south of Spain. Here Molge boscÆ, M. aspera, and M. marmorata originated, the latter passing into France.

Another branch of the Molge tribe turned northward from Greece towards the newly forming Alps; and there originated Molge alpestris and M. palmata, which more recently have spread into England (one at least), Germany, France, Austria, and Southern Italy. Molge vulgaris is an Asiatic species which wandered northward after entering Europe, covering a large area, but never reached the extreme south or south-west. M. cristata—the large Water Newt—has a similar but not quite so extended a range, while M. vittata never managed to cross the borders of Asia Minor. Some of the other species occur in China, Japan, and North America.

None of the tailless Batrachians—the Frogs and Toads—are peculiar to the Alps, but one, viz. Rana temporaria, ascends to the height of no less than 10,000 feet. It is our common British Frog. No other Frog probably ranges so far north or to such heights.

Let us now inquire what the invertebrate fauna of the Alps teaches us. We are told by Dr. Kobelt, the great authority on European land shells, that a uniformity of character marks the Alpine Molluscan fauna (b, i., p. 251). One of the characteristic genera Campylaea—often looked upon as a sub-genus of Helix—is a group containing somewhat flattened conspicuous snails of large size. These are found everywhere in the Alps, and wherever they occur beyond the confines of these mountains, remarks Dr. Kobelt, their origin from the main stock is easily traced. They have been gathered in the Apennines in Sicily, and even beyond the Mediterranean in Algeria. On the Balkan peninsula they occur right down to the most southern point of Greece, but are not met with either in Crete or Asia Minor. One species has been found sub-fossil in Thuringia in Northern Germany.

Another truly Alpine genus, says Dr. Kobelt, is the operculate Pomatias, which in its geographical distribution offers some interesting modifications from that of Campylaea. Less limited to high elevations, it has spread over a greater part of the plains. This has happened especially in France, while in Germany one species advances almost as far north as Heidelberg. In other directions also the genus has travelled beyond the limits of range of Campylaea. Pomatias occurs in the Pyrenees and Northern Spain, in Sardinia and Crete, and may, according to the same author, be expected in Asia Minor, although no species has as yet been met with there. In Greece, again, it has been observed, and numerous species inhabit Tunis and Algeria. Dr. Kobelt connects the wider range of Pomatias with the geological history of the genus (b, i., p. 253). He tells us that species of Pomatias have been found in eocene deposits differing but little from our present forms, while undoubted CampylaeÆ are not met with till we reach the upper Miocene.

Zonites is, according to Dr. Kobelt, a third Alpine genus, whose range scarcely differs from the other two (b, i., p. 254). The centre of distribution lies at present in one of the branches of the most southern Alpine chain which help to form a large portion of the Balkan peninsula. The bulk of the species inhabit that peninsula, the Greek Islands (except Crete) and Asia Minor. Neither in the Tyrol nor in Switzerland do we find any Zonites, and the few species that do occur in the south-eastern Alps only just cross the outliers of these mountains. Between the south-western Alps and the Rhone we again find a Zonites—a remarkable case of discontinuous distribution, since the nearest other habitat of the genus is Monte Gargano in South-eastern Italy, which is known to harbour a good many interesting geographical puzzles.

We still have a good deal to learn as regards the molluscan fauna of Sicily, Sardinia, and Corsica. These islands have scarcely been more than skimmed by conchologists, and Zonites may inhabit one or all of these, which might indicate to us the manner in which this genus travelled from Southern Italy to Provence in the south of France. The distribution of Zonites certainly does not seem to imply an Alpine origin, because it is almost completely absent from the Alps proper. But I do not think my views differ materially from those of Dr. Kobelt, since the Alps, in the wide sense, include the mountains of the Balkan peninsula, where I should feel inclined to locate the ancestral home of the genus.

The small operculate genus Acme is a similar case. Dr. Kobelt places the centre of distribution on the southern slope of the Alps, but scarcely any of the species inhabit the Alps proper. Some occur in France, others in North Africa, Sicily, Southern Italy, and the Caucasus. It is evidently a very ancient genus. The species live in moss or underground, and are not likely to be transported across the sea by accidental or occasional means of distribution.

Still another genus, which resembles Acme in its geographical distribution, is Daudebardia—a small slug-like mollusc with a tiny shell. It does not, however, range nearly so far north or west as Acme, for it occurs neither in the British Islands nor in Spain or the Pyrenees.

I shall not be able to refer to more than a few of the most typical Alpine species of Lepidoptera, but they may be taken as fair examples of the geographical distribution of the rest of the group.

Even those visitors to Switzerland who do not claim to be naturalists have heard of the remarkably handsome and stately Butterfly known as Apollo. To the ardent entomologist, the first sight of this typical Alpine species is a never-to-be-forgotten delight, and he generally brings home with him a rich harvest of specimens. The more experienced Butterfly hunter knows that there are no less than three different kinds of Apollo—or, as we should say more correctly, of Parnassius—in Switzerland. There is first the common Apollo (Parnassius Apollo), then the rarer and more local P. delius, which inhabits more elevated regions, and finally the still scarcer P. mnemosyne, which is only known from the highest mountain ranges. It may be a surprise to those who have accustomed themselves to connect Apollo with the Alps, and who think the two belong together and cannot do without one another, to hear that it is by no means confined to them. It is also found in Scandinavia, France, Spain, Russia, and in Siberia. Parnassius delius is confined to the European Alps and the mountains of Central Asia, while P. mnemosyne is known from the Pyrenees, Sweden, Hungary, Sicily, Russia, and Western Asia. One other Parnassius inhabits Europe, viz., P. Nordmanni of the Caucasus, but all the remaining species of the genus—and there are nearly thirty more—are confined to Central Asia. A few, as we have seen, have reached Europe, some have travelled to the Himalayan Mountains, and others to Western North America. The centre of distribution is certainly in Central Asia, and we have no reason to suppose that the original home in this case does not agree with that centre.

MelitÆa, a genus to which some of our British Fritillaries belong, has also some typically Alpine members. Two of these, viz. M. cynthia and M. asteria, are peculiar to the Alps, the latter being only found at considerable elevations. Most of the remaining fourteen European species are also found in Central Asia. Thus the isolated M. maturna, which in Europe is confined to Lapland, is also known from the AltaÏ Mountains, which again are near the centre of distribution, since some species of MelitÆa range across the Northern Pacific to Western North America.

The small British Mountain Ringlet, and also the Scotch Argus, belong to a genus of butterflies which is very characteristic of the European Alps. But owing to its enormous geographical distribution, its probable home is somewhat difficult to ascertain. Nevertheless it is a noteworthy genus, especially so from the fact that the two British species Erebia epiphron and E. Æthiops are taken at first sight for true Arctic migrants. As neither of them, however, occurs in Scandinavia, Greenland, or Arctic America, this supposition must be abandoned. They must be looked upon as species which once had a wider range in the southern parts of the British Islands, and which have survived in a few isolated localities, where they are apparently on the verge of extinction.

About sixty species of Erebia are known to science, half of which are found in Europe, the remainder in Siberia, the Himalayas, Arctic America, Chili, Patagonia, South Africa, and Madagascar. Though a few do range into these outlying regions of the earth, Central Asia seems to lie near the centre of distribution of the genus, and the probability is that it also was its original home. Most of the European species are high Alpine forms—E. glacialis being met with at a height of 10,000 feet—and these are generally quite peculiar to the Alps, showing that their ancestors came from Asia at an early date, probably by way of Asia Minor and Greece. A few, as for instance E. lappona, range right across to the AltaÏ Mountains from the Alps, and at least one—E. melas—is found in Greece. Erebia migrations seem therefore to have taken place by the Southern or Oriental route at different geological periods. But some of the European species which are more or less confined to the plain, and are either absent from Switzerland or do not reach the higher elevations, appear to me to have come by the more direct northern or Siberian highway, at a still more recent period. These are Erebia Æthiops, medusa, ligea, and ambla.

Only one species of the well-known Polar genus Œneis, viz. Œ. aËllo occurs in the Alps. It has always been taken at very high elevations near the verge of the snow-line on the most lofty parts of the Simplon Pass, and other similar situations. Altogether about a dozen species of this genus of butterfly are known, most of which are confined to the polar regions of the Old World and the New, though some have found their way to the extreme south end of South America, in what manner is still a mystery. Like the preceding genera, this also appears to have emerged from Central Asia. The genus, too, is closely allied to the last, and though its range is not quite so extensive, it resembles it in many respects. The Alpine species of Œneis came to Europe by the Oriental route. But the Lapland species—at any rate Œ. jutta and Œ. bore—have taken a somewhat circuitous route to reach our continent. They first migrated from Asia to North America, and then by the old land-connections by way of Greenland to Lapland. It is noteworthy that Professor Engler felt convinced (cf. p. 171) that the occurrence of many of the Arctic plants in North Scandinavia and Siberia could be best explained by the assumption of such a migration from Asia vi North America to Europe rather than by the shorter route.

There are far more Alpine beetles than butterflies, but their geographical distribution is less well known, and it is therefore not at all safe to base important conclusions as to the origin of a fauna on that group alone; however, as far as my limited knowledge of the Coleoptera of the Alps goes, their general range seems to agree perfectly with other orders of insects. Many can also be traced to an Asiatic home, and the route they came by is the Oriental and not what I have called the Siberian.

Take, for instance, the genus Nebria, of which we have one species in England—a black insect with a bright reddish-yellow border and long light legs—known as N. livida. There are about eighty European species, most of which are confined to the Alps, the Caucasus, the Pyrenees, Spain, and Greece. The genus, however, ranges all over the Holarctic Region, that is to say roughly, over Europe, Central and Northern Asia, and North America. The centre of distribution lies in Central Asia. If the genus had poured into Europe by the northern or Siberian route, we should probably now find many species in Northern Russia, Germany, and France; but this is not the case, and we may therefore assume with some justification that the Southern or Oriental route was the only one available at the time when the bulk of the species of Nebria wandered to Europe. Many of the Nebrias occur in Switzerland and in the Alps, generally on the margins of the snow-fields and glaciers, like N. Germari and Brunii. Others, for example, N. atrata, ascend to the highest limit of animal life, having been observed at a height of over 10,000 feet.

Of the remaining orders of insects we know as yet very little. Central Asia and even Siberia are only beginning to be explored, and their invertebrate fauna—except Lepidoptera and Coleoptera—is practically unknown. However, I cannot conclude this short summary of some of the more characteristic Alpine animals without referring to the Grasshoppers which are so conspicuous in the mountains. The mountain air simply rings during a bright summer's day with the loud and cheerful song of millions of these insects. It is one of the most vivid impressions a tourist brings back from Switzerland—this constant shrill sound issuing from an apparently invisible source.

Among these Grasshoppers there are some highly characteristic Alpine genera. Pezotettix—formerly known as Podisma—is one of these. P. alpinus is almost confined to the high Alps; with P. mendax it occurs in lower levels chiefly towards the south-east, that is to say, in the direction of Hungary, Servia, and Dalmatia. P. frigidus occurs not only in the high Alps, but also in Lapland. P. Schmidti and P. salamandra are found in Carinthia, Servia, and Transylvania; and one species also inhabits the Pyrenees and another the Italian Mountains. Finally, the only English species of Pezotettix, viz. P. pedestris, has been taken in Sweden, Denmark, and then again in Austria, Hungary, Servia, etc., as far east as the Volga, and also on the high Alps, in Sardinia and the Abruzzi Mountains in Italy.

Very little, as I remarked, is known of the Asiatic range of this genus, but either the same or a closely allied one has many representatives in North and South America. Whether Pezotettix is therefore of Asiatic origin we cannot positively affirm, but whatever view we take, the general range of the European species indicates that the migration took place from the Alps in a south-easterly direction, or to them in a north-westerly one. That is to say the Oriental route, and not the Siberian, was utilised by the migrants.

Fortunately, we know a little more about another Grasshopper genus, called Chrysochraon. There are only two species, one of which, Chr. dispar, has been found from Northern France to the mountains of Servia, but not in the Alps. The other, Chr. brachypterus, has a somewhat similar range in the plain; but, moreover, it inhabits the Alps up to a considerable height. It is interesting to note that both these Grasshoppers again turn up on the Amur in Eastern Siberia.

In conclusion, I might mention one more Grasshopper, viz. Tettix, because it includes a species—T. bipunctatus—which, though well known in the plain of Middle and North Europe, ascends the Alps to a height of nearly 10,000 feet. It is one of the few instances I know of an animal occurring in the same form in such an enormous range of altitude—from sea-level to the highest regions where animal life is known to exist. It is also known from Asia Minor and Siberia. T. subulatus has a similar distribution, but is more common in Southern Europe than the other. T. fuliginosus occurs in Lapland and Siberia, T. meridionalis and T. depressus all along the shores of the Mediterranean. There can be no doubt that here also we can trace migration to or from Siberia, and again, as on previous occasions, by the Oriental route.

We now possess a fair general idea of the fauna of the Alps. We have learned that a good many of the animals are indigenous, and that others have migrated to the Alps by various routes. The majority of these have come from Central and Southern Asia with what has been described as the Oriental migration. A much smaller number have reached the Alps from the north and the west, but none of the latter are among the high Alpine forms. What will be the most surprising revelation is that the eastern species, which arrived in Europe with the Siberian migration, are practically absent from the Alps proper. No doubt some of them still survive in the lowlands of Switzerland and the Tyrol, but none of the true Alpine fauna owes its origin to the Siberian migration. If we compare the Alpine mammals with the Siberian forms which reached England (vide p. 202), we at once perceive the difference. We should expect to find in the Alps—if not the Reindeer and the Glutton—the Arctic Fox, the little Pica, the Lemmings, and the pouched Marmots. It might be urged that some of the smaller Siberian carnivores and rodents do inhabit the Alps. So they do. The Stoat and Weasel have found such a congenial home in Europe, both in the plain and mountains, that they have spread rapidly to the latter, and no doubt reached within a comparatively short time the great heights at which they now occur in the Alps. But the Voles (Arvicola) have scarcely spread beyond the region of fields and cultivated ground. A height of 5000 feet at the most marks their maximum altitude in the Alps.

The fauna which reached the Alps in miocene and pliocene times, as well as the indigenous element, must have survived the Glacial period in their mountain home. Though I think that the conditions of the climate at that time and the size of the Scandinavian glaciers have been greatly exaggerated, there can be no doubt at all about the enormous size of many of the Alpine glaciers at this period. The climate was probably much moister but not colder than what it is now, possibly warmer. The snowfall was therefore greater, so that glaciers filled many of the lower valleys of Switzerland which are now quite free from ice, and even invaded the plain. But there is no reason whatsoever why the Alps should not even then have supported a luxuriant fauna and flora as they do now. Possibly many of the miocene plants and animals became extinct then, but extinction of species occurs at the present day. We hear complaints that the Chamois and the Steinbock have nearly vanished; we know that the Marmot is now much scarcer than it used to be, and that the Edelweiss and many other plants are more and more difficult to find, and seem rapidly to disappear. No doubt all this is in a great measure due to the influence of man, but not altogether. There is a constant struggle for existence going on among the animals and plants themselves—the stronger and fitter species driving the less fit and weaker into a corner, where they finally succumb. This happens now just as it did in pliocene and pleistocene times, and need not imply change of climate.

As soon as the Miocene sea to the north of the mountains had retreated, a portion of the Alpine fauna poured into the plain, and many species have found their way to the British Islands, a few to Scandinavia and Russia. Westward too, the sea soon after retired and opened a way for those Alpine species which were vigorous enough to extend their range in that direction. South-eastward, of course, a highway had long ago been open, and Alpine forms which were able to migrate towards the incoming Oriental stream, had no difficulty in doing so. When they arrived in Greece, some turned westward again and populated Sicily, Southern Italy, Sardinia, Corsica, and Northern Africa, while others crossed over to Asia Minor, which was then connected with Greece, and wandered towards the Central Asiatic or the Himalayan Mountains.

But, as I remarked, few of the typical Alpine species reached Scandinavia and Lapland. I have already referred to the similarity between the Northern Scandinavian and the Alpine faunas in a previous chapter, and I have shown that this resemblance cannot altogether be explained by the supposition of an interchange in the faunas of the two regions. That this has taken place to some extent is probable, but the resemblance appears more especially due to the fact that the Alps and Scandinavia have been peopled from the same centres of distribution.

In order to make this matter quite clear, I will give a familiar example as an instance of the manner in which the present distribution can be explained without taking recourse to direct migration from the Alps to Scandinavia or vice versÂ. The example I will take is that of a family of birds, not only of extreme interest from the fact of its northern range, but also from the pleasure it gives to those addicted to sport. This is the grouse family, the TetraonidÆ.

Let us commence with our British Grouse (Lagopus scoticus), which is peculiar to the British Islands. In Norway we find a Grouse (L. albus) which differs in habit, and in the fact of its turning white in winter; otherwise it is so closely allied to our Grouse that many ornithologists do not separate them specifically. No doubt the British Grouse is a descendant of this Scandinavian Willow-grouse. The latter is known also to inhabit Greenland and Arctic North America, and it is even found beyond Behring Straits in Northern Siberia. En route between Scandinavia and Asia, travelling in a westward direction, we meet with two other very local species of Grouse, which may be looked upon as offshoots of L. rupestris—viz., L. hyperboreus of Spitsbergen, and leucurus of Western North America. In Asia we then again find two kinds of Grouse, very closely related, and by some indeed regarded as belonging to the same species. These are L. rupestris and L. mutus. Mr. Ogilvie-Grant tells us of the former (p. 49), that it is merely a more northern rufous form of L. mutus, and that it goes through similar changes of plumage. In summer the males are readily distinguishable, but in winter it is impossible to tell one from the other. "L. rupestris taken as a whole," says Mr. Ogilvie-Grant, "appears to us barely specifically distinct from L. mutus." L. rupestris occurs not only in Northern Asia, but crosses the Behring Straits to Arctic America, being still found on the Aleutian Islands, which represent the last remains of the former land-bridge between Asia and North America, then eastward to Greenland and Iceland. However, while this form does not cross the confines of Asia in a westerly direction, its near relative L. mutus—better known as the Ptarmigan—does; and may perhaps have entered Europe as a Siberian and also as an Arctic migrant. It is still found in the Ural Mountains, in Finland, and the highlands of Scandinavia. It is gradually being driven out of the Alpine lowlands, while it has long ago disappeared from Germany, France, and Austria—in fact, from all the lowlands of Europe. It has also been met with in the Pyrenees and in some of the Spanish mountains. Similarly, the bird has become extinct in England and Ireland, while it is becoming more and more scarce in Scotland. The centre of distribution of the genus lies in Arctic America, and from there the genus has spread to Europe and Asia. L. albus and L. mutus appear in our continent chiefly as Arctic migrants.

The Black Grouse (Lyrurus tetrix) belongs to a closely allied genus, which has only two species. One of these is very local in distribution, being confined to the Caucasus, but the smallness of range is to some extent compensated for by the peculiarity of its name, which is L. mlokosiewiczi. The Black Grouse, on the contrary, is widely distributed. It inhabits Northern Asia from the Pacific to the Ural Mountains, and extends as far south as Pekin and the Tian Shan range. In Europe it is found from the extreme east to the Pyrenees, the Apennines on the south, and to Great Britain and Scandinavia in the north. It is important to note its absence from Spain, the Mediterranean islands, and Ireland; and we have learned that it is one of those Siberian migrants which have succeeded in establishing themselves in the Alps.

The Capercaillie (Tetrao urogallus)—another great favourite with sportsmen—is now generally separated generically from the Black Grouse, though they are of course near relations. Its range greatly resembles that of the Black Grouse, except that it does not go quite as far east in Siberia, not having been met with beyond Lake Baikal. From there it is found westward as far as the Pyrenees. It occurs also in the Carpathians and the Alps. In England, where it used to be known by the name Cock of the Wood, it became extinct at some remote period in history, while it lingered on in Scotland and Ireland until the end of the last century. In Scotland it has been reintroduced into several counties, and being protected, it appears to spread from these artificial centres of distribution.

Like the Black Cock, the Capercaillie is a Siberian migrant, and it is one of the few Siberian species which have reached Ireland, as I have had occasion to mention in dealing with the origin of the British fauna. Two other species of Capercaillie and an allied genus (Falcipennis) are met with in the extreme north-east of Siberia, and six other genera, all belonging to the grouse family, are confined to North America. We have therefore a very intimate relationship between the grouse of Asia and those of North America, some species even ranging right across the two continents.

The last genus of this very interesting family is Tetrastes. This grouse is not familiar to British ornithologists, since it is entirely absent from the British Islands. But sportsmen who have tramped over Scandinavia know it well by the name of Hazel Grouse. It is ashy grey in colour, barred and vermiculated with black. The Common Hazel Grouse (Tetrastes bonasia) is found from Northern Spain in the west right through the mountainous parts of Central and Northern Europe and Northern Asia to Kamtchatka and the Russian convict island of Saghalien in the Pacific. Besides the Common Hazel Grouse, two other species are known, one from Eastern Russia and the other from China.

Having now shortly reviewed the whole grouse family, we have seen that, although some species live within the Polar Circle, the majority are more or less confined to the more temperate or rather the less arctic parts of the Northern Hemisphere. They are quite absent from Southern Asia and even the southern parts of North America, and almost so from the Mediterranean basin. The whole range of the family is therefore suggestive of a northern origin, and this view agrees perfectly with all the details of distribution. The centre of distribution lies in Northern Asia, or in Arctic North America. From there the great genus Lagopus spread east and west, reaching Europe by these vastly divergent routes at a time when the physical geography was very different from what it is to-day. Several of the species common to the Alps and Scandinavia have migrated from Siberia direct to Eastern Europe. But we can now imagine how from a similar centre in Asia—perhaps at a rather more remote time—a species spread eastward across North America and Greenland to Scandinavia, and westward along the mountain ranges of the Tian Shan and the mountains of Asia Minor to Greece, and finally to the Alps. We should then have the same species in the Alps and in Scandinavia, not far removed from one another; but how different were their paths of migration! This, however, is not an imaginary instance. Such a migration must have actually taken place in a good number of instances among the terrestrial invertebrates and also among plants.

The view still current among many zoologists and botanists, that animals and plants were driven down into the plain from the mountains of Europe during the height of the Glacial period and there lived together till the return of a more genial temperature, when they retreated to their mountain homes, is a very plausible one. During their sojourn in the plain, the plants and animals—say from Scandinavia—intermingled with those from the Alps; and when the time of separation came, many Alpine forms retired northward with the Scandinavians, while many Scandinavians would go with the Alpines to their home. In this way the similarity between the Alpine and Scandinavian faunas and floras is assumed to have been brought about. These theories, first promulgated by Edward Forbes, were hailed with general satisfaction by the scientific world. Even Darwin says of them (p. 331), that grounded as they are on the perfectly well-ascertained occurrence of a former Glacial period, they seemed to him to explain in a satisfactory manner the present distribution of the Alpine and Arctic productions of Europe. To the present day this view meets with much favour among naturalists. It is somewhat similar to one which has recently been strongly supported by Professor Nehring and accepted by Professor Th. Studer and many others. They have never made it quite clear whether the pre-glacial fauna and flora are supposed to have been absolutely destroyed by the glacial climate, or whether part of them have been able to take refuge somewhere in the south; but the great mass of our Alpine plants and animals are believed to have been derived from the Siberian invasion, which I have fully described in the fifth chapter. This invasion spread over the European plain, and when the climate ameliorated, both animals and plants migrated north and south to the mountains. This view agrees with the earlier theory, except that the adaptation to Alpine conditions would, according to the former, have taken place since the close of the Glacial period, during which time no such modification or change of species seems to have been produced in other parts of the world. The characteristic fauna of the Alps, as has been gathered from the preceding pages, is mainly of Central Asiatic rather than of Siberian origin. Migration to the Alps took place by the Oriental route long before the Siberian invasion. Some of the species of the latter have penetrated to the Alps, but these Siberian species have not given to the fauna of the highest European mountain range the striking character with which we all associate it.

Before concluding this chapter, a few remarks on the botanical aspect of the Alpine problem might not be out of place. It will enable us to judge which of the views indicated is the more probable, and will add to the interest which may have been aroused by the perusal of this sketch of the fauna of the Alps. Very much the same train of argument was applied as to the course of events in the formation of the Alpine flora as in the case of the fauna. The plants were all supposed to have been killed or driven away by the arctic temperature of the Glacial period, and their place taken by new migrants from the north or east when the climate ameliorated.

Professor Engler, one of the highest living authorities on the geographical distribution of plants, is of opinion (p. 102) that a large number of the indigenous Alpine species did not originate till after the close of the Glacial period, because so many of them are absent from the Sierra Nevada in Spain, where the condition for their well-being exists, while many have evidently spread from the Alps to the Carpathian Mountains and to the Pyrenees. He does not believe that a glacial flora could have existed in the plain between the Sierra Nevada and the Pyrenees during the Glacial period (p. 109). In speaking of the Caucasus, Professor Engler informs us (p. 117) that a good many species which do not occur in the Alps reached these mountains from Siberia. Apart from the northern glacial plants, the Caucasus has only few species in common with the Alps, more with the Balkan mountains and Northern Persia. Turning to Afghanistan, our author mentions (p. 121) a few Alpine plants as occurring in that country, and likewise in the Caucasus and the Himalayas. He considers it probable that the route of migration of some glacial plants from the east to the west, and vice versÂ, lay across the Afghan mountains. Many of our Alpine plants occur in the Siberian mountains, but in the AltaÏ and Eastern Siberia generally a considerable number of these are by no means confined to the mountains (p. 125). They are also met with in the lower regions, and the rare Alpine Edelweiss (Leontopodium alpinum) frequently covers wide tracts in the plain, and is passed by almost unnoticed by the Siberian botanist.

Special attention is drawn by Professor Engler to the fact (p. 130) that several of the Siberian plants inhabit the Alps and the Caucasus, but are not found in Scandinavia. And from this he deduces the conclusion that part of the Siberian flora migrated in a south-westerly direction towards the Caucasus and the mountains of the Mediterranean area, exactly in the manner indicated in respect to the fauna of the Alps. We learned that the migration to the Alps from Central and perhaps also parts of Northern Asia took a south-westerly course first, and was then followed by one in an easterly direction. I called the former the Oriental migration and the latter the Siberian. Later on Professor Engler states (p. 142) that the main mass of the Siberian forms of plants certainly wandered westward to the south of the Ural. This is proved by the numerous glacial plants found in the Caucasus, while the glacial flora of the Ural Mountains is poor. Finally, he expresses the opinion that the probability of most of the Alpine plants occurring in Arctic Siberia, having wandered from the Alps, by way of Scandinavia, Greenland, and North America, to North-eastern Siberia, is greater than the direct migration from Europe to Siberia (p. 143).

Another continental writer on the Alpine flora who deserves special mention is Dr. Christ. His observation that Alpine plants by no means suffer from a high temperature (p. 309), but solely from a drying up of the soil, seems to me to point to the correctness of the view I have expressed on several occasions, that these plants have originated long before the Glacial period at a time when the climate was warmer and moister than it is now. It seems quite natural to Dr. Christ that the Arcto-Alpine flora should have originated in Asia, but he excepts thirty species which are absent from Northern Asia, though occurring in America (p. 327). These he thinks have penetrated direct from America to the Alps by way of Scandinavia, since no less than twenty-three still occur in the latter country. In the human population of the Alps, he continues (p. 336), one can distinguish an indigenous Celtic race, a Germanic colder and more apathetic race, and a more lively Roman one. The flora is composed of quite a similar mixture. We find also an indigenous element—an Arctic and a Mediterranean one. The last element is a survival of the Tertiary flora of the Central European plateau (p. 532). The plants were driven down to the shores of the Mediterranean, and it is only after the retreat of the glaciers that a few of them have been able to regain their ancient territory. The incoming Asiatic and North American flora likewise retired at the end of the Glacial period to the Alps and the Arctic countries, and left isolated traces of its former abundance on the North European plain. The bulk of the Arctic or Alpine flora is held to be of Asiatic origin. Since Siberia shows little trace of having been glaciated, owing to the dryness of the climate, a rich flora was able to develop there, which spread into Europe as soon as the vanishing glaciers made room for it.

These are the views of Professor Engler and Dr. Christ. They agree in so far as both of them maintain that the bulk of the Alpine flora is post-glacial—that is to say, that it has developed quite recently, or migrated to the Alps after the glaciers had retreated from the plain to the mountain recesses. It is assumed by Dr. Christ that while Europe was practically uninhabitable, a rich flora survived in Northern Asia, because the climate there was too dry for the development of glaciers. Due consideration in this interesting speculation, however, is not given to the fact which he himself emphasised, that Alpine plants are particularly prone to suffer from a dry climate. Even a moderately dry cold kills most of them. How can we then reconcile this fact with the theory of their origin in a dry and intensely cold climate? I quite agree with the views as to the Asiatic origin of the bulk of the Alpine flora, while the dry state of the Siberian climate is certainly indicated by the extremely feeble development of the glaciers during a large part of the Glacial period. We know, however, that in Pliocene and even in early Glacial times the atmospheric conditions must have been very different in Siberia. A great slice of Central Asia was under water, and numerous freshwater lakes covered the lowlands in the north, so that the climate must have been damp though not cold enough for the formation of extensive glaciers. Everything, in fact, seems to indicate that the migration of the Asiatic Alpine flora took place at a very early date—probably long before the Glacial period—either by the Oriental or by the Arctic route vi North America, Greenland, and Scandinavia. But would this not necessitate a survival of the Alpine plants in the Alps themselves? That is the view which has already been expressed with regard to the fauna, and the flora probably followed a very similar course. This is by no means a novel theory, however, and though unfortunately an untimely death has removed one of our very best authorities on the Alpine flora before he had completed his life's work, we have some indications in the earlier writings of John Ball that his opinions on the origin of that flora did not coincide with those held by the leading continental authors. To quote the words of this distinguished botanist (p. 576): "Is it credible that in the short interval since the close of the Glacial period hundreds of very distinct species and several genera have been developed in the Alps, and—what is no less hard to conceive—that several of these non-Arctic species and genera should still more recently have been distributed at wide intervals throughout a discontinuous chain some 1500 miles in length, from the Pyrenees to the Eastern Carpathians? Nor would the difficulties cease there. You would have left unexplained the fact that many of the non-Arctic types which are present in the Alps are represented in the mountains of distant regions, not by the same, but by allied species, which must have descended from a common ancestor; that one species of Wulfenia, for example, inhabits one small corner of the Alps, that another is found in Northern Syria, while a third allied species has its home in the Himalaya." Mr. Ball is of opinion (p. 584) that the effects of the Glacial period have been greatly overrated. "Even during the period of maximum cold the highest ridges of the Alps were not completely covered with snow and ice; for we still see by the appearance of the surface, the limit above which the ancient ice did not reach, and in the middle zone the slopes that rose above the ancient glaciers had a summer climate not very different from that which now prevails. In my opinion the effect of the Glacial period on the growth of plants in the Alps was to lower the vertical height of the zones of vegetation by from one to two thousand feet." He acknowledges that there was probably a moderate diminution of the mean temperature of Europe with an increased snowfall, so as to cause a great extension of glaciers on all the mountains of Northern Europe. "But that the climate of Middle Europe was such that the plants of the high Alps could spread across the plains seems to me an improbable supposition" (p. 584).

On the Continent, also, some botanists seem to feel that Forbes's theories of the origin of the Alpine flora, which were at first hailed with such delight, and accepted by almost every naturalist as the final verdict, must be modified in the light of recent researches. Professor Krasan believes that many plants which now live in the high Alps flourished in pliocene times at sea-level (p. 37). "Especially the evergreen species exhibit the impression of an originally mild climate—of a climate without winter frosts—for otherwise the plants would have developed into species with deciduous leaves." To the favourable conditions, consisting in periodic snowfalls and high summer temperature, must be attributed the fact that in the highlands so many more species from Tertiary times have survived than in the plains. The temperature was probably much higher during the Glacial period than is generally believed. The climate was more moist, thus contributing to an abundant snowfall, while the survivors of ancient Tertiary times were able to repeople the parts which were temporarily devastated by the advancing glaciers.

In so short a chapter it is impossible to deal with the Alpine fauna in a manner more deserving of this theme. I have merely sought to give a sketch of the general outlines of the subject and to suggest another possible mode of origin of Alpine animals than that currently believed in by naturalists. It is to be hoped these suggestions will be useful to those intending to reinvestigate the problems raised in this chapter. When our knowledge of the fauna of Asia is more complete, it will be possible to give a more thorough and in many respects a more satisfactory history of the European fauna than at present.

SUMMARY OF CHAPTER VIII.

In early Tertiary times the area now covered by the European Alps was covered by the sea. Islands slowly rose above the surface of the waters, which finally coalesced to form a peninsula connected with the mainland in the east. Animals now began to invade the new territory which continued to rise, while the sea retired farther and farther to the north and south. During the Pliocene Epoch the sea ceased to wash the northern shores of the Alps, and both emigration and immigration became possible in that direction, and also from and to the west.

The Alpine fauna and also the flora are made up of a number of elements, the eastern one being the oldest. The latter is represented in the Alps by the older and newer Oriental migration. The general range of the Alpine Steinbock, Chamois, Marmot, Vole, Shrew, and Hare are specially referred to. The Alpine birds are few in number, and all of them are readily traceable to an Asiatic ancestry. Among the Amphibia, the Salamanders are considered of Alpine origin.

Dr. Kobelt tells us that a uniformity of character marks the Alpine molluscan fauna. Campylaea,—often considered a sub-genus of Helix,—Pomatias, Zonites, are looked upon as truly Alpine genera. For very long periods the Alps seem to have received no addition to their molluscan fauna from other areas. The case is very different with the Lepidoptera, some of the most striking species being evidently Asiatic immigrants. Some examples of Coleoptera and Orthoptera are mentioned, and their origin discussed.

We find as the result of these considerations that the majority of the Alpine species are either indigenous or have come from Asia with the Oriental migration. None of the northern or western immigrants appear to be among the characteristic Alpine species, and it seems that the Siberian migrants have not retired to the Alps, as some naturalists have been led to suppose. It is evident that the fauna must have survived the Glacial period on the Alps, though according to geological evidence glaciers of enormous size originated on these mountains.

The identity of many Alpine species with Scandinavian ones appears at first sight due to a direct migration from the Alps to Scandinavia or vice versÂ. Perhaps such a migration has taken place to some extent, but it is probable that from a Central Asiatic centre some species spread across Arctic America into Northern Europe, and also westward to the Alps. The Grouse family forms an interesting example.

There are two older theories which explain the similarity between the Scandinavian and Alpine faunas. Forbes's view, which gained most adherents among naturalists, was that the Scandinavian and Alpine animals were driven into the plain by the cold during the Glacial period, and when they ultimately regained their homes, some individuals of the northern species moved southward, and a few of the southern ones northward. By the more recent theory of Nehring, the Siberian animals which invaded our continent from the east, and then spread northward to Scandinavia and southward to the Alps, formed the nucleus of the faunas of these two areas. The objections to both of these views are fully set forth in this chapter.

A few remarks on the botanical aspect of the Alpine problem conclude the chapter. The origin of the flora has been explained in a very similar manner to that of the fauna. But already Ball and Krasan have raised their voices against the current theories, as the facts of distribution appear to them more satisfactorily explained on lines more consonant with those which I have used in discussing the origin of the Alpine fauna. One of the most important conclusions obtained by this study of the flora in conjunction with the fauna, is that I have emphasised in most of the preceding chapters—viz., that the Glacial period in Europe was not a time of extreme cold, and that its destructive effect on the animals and plants was by no means such as is currently believed.