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box, termed an "analyzer," contains the series of evaporating chambers, each communicating with the one below by means of a valved tube, which allows fluid to escape from the upper to the lower chamber only, and having the dividing partition of each chamber perforated with fine apertures, to allow the steam which U admitted from below to pass from chamber to chamber through the shallow layer of wash of each. A safety or escape valve is also fitted to each chamber. The already heated wash enters the uppermost of these chambers in a continuous regulated stream, is gradually deprived of its alcohol by the steam as it passes from chamber to chamber, and at last escapes into the lower large receiver, from which it flows off after attaining a certain depth. The third part of the apparatus also consists of a square upright box, termed a " condenser," divided into compartments by means of finely perforated plates, and in each chamber is a link of the tube which carries the eold wash onwards to supply the evaporating chambers just described. The alcoholic vapours escaping from the uppermost of the evaporating chambers are carried by pipes to the lowermost of these chambers, and are partly condensed by each successive chamber being colder than the one below it, in consequence of the wash entering the pipes from above, and only getting gradually heated by contact with the alcoholic vapour as it advances from chamber to chamber. As in the lowest of these chambers the heat is greatest, the alcoholic vapour or the condensed spirit contains a large amount of water; but as the chambers are successively cooler, the alcoholic vapour and condensed spirit at last arrive at a temperature only sufficient to convert spirit of the strength wished into vapour, and by an adaptation of valves, the substitution of an impervious partition for the perforated plate, and the admission of the alcoholic vapour into the chambers cooled by the passage of the cold wash in its contained pipes, that spirituous vapour is condensed, and the spirit is drawn off at one operation, of the very strength which it ought to have, and of the utmost purity.

Flat-bottomed and fire-heated stills are considered the best for the distillation of malt spirit, as by them the flavour is preserved. Coffey's still, on the other hand, is the best for the distillation of grain spirit, as by it a spirit is obtained almost entirely destitute of flavour, and of a strength varying from 55 to 70 over proof. Spirit produced of this high strength evaporates at such a low temperature that scarcely any of the volatile oils on which the peculiar flavour of spirits depends are evaporated with it, hence the reason why it is not adapted for the distillation of malt whisky, which requires a certain amount of these oils to give it its requisite flavour. The "spirit produced by Coffey's still is, therefore, chiefly used for making gin and factitious brandy by the rectifiers, or for being mixed with malt whiskies by the wholesale dealers.

As the preparation of alcoholic spirit is the most important industry in which the operation of distillation occupies a prominent place, the establishments in which the manufacture is conducted are known as distilleries. But there are many other important industries in which distillation is an essential feature, being in them employed either for the separation, purification, or concentration of various products. A large proportion of the essential oils are, for example, obtained by the distillation of the substances containing them from water or a mixture of salt and water. The treatment of other bodies in which distillation plays a part will bo found under their respective headings. (w. ».—J. Pi-)

DISTRESS is one of the few cases in which the law still permits an injured person to take his remedy into his own hands. Other instances mentioned in the text-books are self-defence in the case of a personal assault, the

reseizure of property wrongfully taken away, the abatement of nuisances, ic. Distress differs from these as being a remedy for what is really a breach of contract, and it is the only case of the kind in which such a remedy is given. It is the right which the landlord has of seizing the personal chattels of his tenant for non-payment of rent. Cattle damage feasant (doing damage or trespassing upon a neighbour's land) may also be distrained, i.e., may be detained until satisfaction be rendered for-the injury they have done. The cattle or other animals thus distrained are a mere pledge in the hands of the injured person, who has only power to reUin them until the owner appear to make satisfaction for the mischief they have done. Distress for rent was also at one time regarded as a mere pledge or security; but the remedy, having been found to be speedy and efficacious, was rendered more perfect by enactments allowing the thing taken to be sold. Blackstone notes that the law of distresses in this respect "has been greatly altered within a few years last past." The legislature, in fact, converted an ancient right of personal redress into a powerful remedy for the exclusive benefit of a single class of creditors, viz., landlords. Now that the relation of landlord and tenant in England has come to be regarded as purely a matter of contract, the language of the lawbooks seems to be singularly inappropriate. The defaulting tenant is a "wrong doer," the landlord is the "injured party; "any attempt to defeat the landlord's remedy by carrying off distrainable goods is denounced as " fraudulent and knavish." The operation of the law has, as we shall point out, been mitigated in one important respect by a recent Act, but it still remains an almost unique specimen of one-sided legislation.

At common law distress was said to be incident to rent service, and by particular reservation to rent charges; but by 4 Geo. IL c. 28 it was extended to rent seek, rents of assize, and ckief rents (see Kent.) It is therefore a general remedy for rent certain in arrear. All personal chattels are distrainable with the following exceptions :—1, things in which there can be no property, as animals ferce natural; 2, things in actual use; 3, thiugs delivered to a person following a public trade, as a horse sent to be shocd, Ac.; 4, things already in the custody of the law; 5, money, unless placed in a sealed bag; 6, things which cannot be restored in as good a plight as when distrained; 7, fixtures; 8, beasts of the plough and instruments of husbandry; 9, instruments of a man's trade or profession. These exceptions, it will be seen, imply that the thing distrained is to be held as a pledge merely—not to be sold. They also imply that in general any chattels found on the land in question are to be available for the benefit of the landlord, whether they belong to the tenant or not. This principle worked with peculiar harshness in the case of lodgers, whose goods might be seized and sold for the payment of the rent due by their landlord to his superior landlord. Now, however, by the Lodgers' Goods Protection Act (31 and 35 Vict. c. 79), where a lodger's goods have been seized by the superior landlord the lodger may serve him with a notice stating that the intermediate landlord has no interest in the property seized, but that it is the property or in the lawful possession of the lodger, and setting forth the amount of the rent due by the lodger to his immediate landlord. On payment or tender of such rent the landlord cannot proceed with the distress against the goods in question. And originally the landlord could only seize things actually ou the premises,, so that the remedy might be defeated by the things being taken away. But by 9 Anno c 14, and 11 Geo. IL c. 19, he may follow things fraudulently or clandestinely removed off the premises within thirty days after their removal, unless they have been in the meantime bona fide sold for a valuable consideration. The sixth exception mentioned above was held to extend to sheaves of corn; but by 2 Will, and Mary c 6, corn, when reaped, as well as hay, was made subject to distress.

Excessive or disproportionate distress exposes the distrainer to an action, and any irregularity formerly made the proceedings void ab ■initio, so that the remedy was attended with considerable risk. The statute 11 Geo. II. c. 19, before alluded to, in the interests of landlords, protected distresses for rot! from the consequences of irregularity. In all cases of distress for rent, if the owner do not within

five days replevy the same with sufficient security, the thing distrained may be sold towards satisfaction of the rent and charges, and the surplus, if any, must be returned to the owner. To "replevy" is when the person distrained upon applies to the proper authority (the registrar of the county court) to have the thing returned to his own possession, on giving security to try the right of taking it in an action of replevin.

Duties and penalties imposed by Act of Parliament are sometimei enforced by distress.

DISTRIBUTION

THE subject specially discussed under this heading is the Distribution of Life, Animal and Vegetable, in Space and Time.

So long as each species of organism was supposed to have had an independent origin, the place it occupied on the earth's surface or the epoch where it first appeared had little significance. It was, indeed, perceived that the organization and constitution of each animal or plant most be adapted to the physical conditions in which it was placed; but this consideration only accounted for a few of the broader features of distribution, while the great body of the facts, their countless anomalies and curious details, remained wholly inexplicable. But the theory of evolution aud gradual development of organic forms by descent and variation (some form of which is now universally accepted by men of science) completely changes the aspect of the question and invests the facts of distribution with special importance. The time when a group or a species first appeared, the place of its origin, and the area it now occupies upon the earth, become essential portions of the history of the universe. The course of study initiated and so largely developed by Mr Darwin has now shown us the'marvellous interdependence of every part of nature. Not only is each organism necessarily related to and affected by all things, living and dead, that surround it, but every detail of form and structure, of colour, food, and habits, must—it is now held—have been developed in harmony with, and to a great extent as a result of, the organic and inorganic environments. Distribution becomes, therefore, as essential a part of the science •f life as anatomy or physiology. It shows us, as it were, the form and structure of the life of the world considered as one vast organism, and it enables us to comprehend, however imperfectly, the processes of development and variation during past ages which have resulted in the actual state of things. It thus affords one of the best tests of the truth of our theories of development; because, the countless facts presented by the distribution of living things in present and past time must be explicable in accordance with any true theory, or at least must never directly contradict it.

From these indications of the scope and bearing of the subject, it will be seen that its full and adequate treatment would require volumes, and would necessarily involve an amount of details only suited to specialists in the various branches of natural history. All that can be attempted here is to givo such a general sketch of the whole subject as to place the reader in possession of the main results arrived at, and enable him to comprehend the bearing of the more detailed information he may meet with jliewhere.

Arrangement of the Subject.—The three great heads under which the various matters connected with distribution may be classed are—1st, the geographical distribution of living organisms; 2d, the geographical distribution of extinct organisms; and 3d, the geological succession of the chief forms of life. Owing, however, to the fact that the study

of animals and of plants form very distinct sciences, and that there are special peculiarities in the phenomena presented by each which require to be carefully discriminated, it is found to be necessary to make a primary division of the subject into the distribution of annuals and of plants respectively.

DISTRIBUTION OF ANIMALS.

Thn distribution of living animals in space naturally forms the first division of our subject, both because the phenomena are simpler and better known, and because it puts before us the main problems and difficulties to the solution of which the other divisions furnish the key. Animals may be roughly divided into two great series, broadly distinguished as regards their mode of life—the terrestrial and the aquatic; and for the purpose of our present study these divisions are of primary importance, because that element which limits the range of the one class offers a free passage to the migrations of the other, and vice versa. The first series is by far the most important. It is the best known, and includes almost all the higher animals; while the variety and interest of the various land divisions of the globe are far greater than in the case of that portion of its surface covered by water. We shall therefore consider first, and with a greater amount of detail, the distribution of land animals, including among them the fresh-water forms whose range is limited by the same general conditions.

The Geographical Distribution or Land Animals.

As soon as we begin to examine into the distribution of animals over the land surface of the globe, we - meet with two very distinct and sometimes conflicting classes of facts, which may be conveniently grouped as climated and geographical distribution. The first is the most obvious, and was long considered to be the most essential, since we find that not only many species, as the polar bear and musk sheep, are strictly limited to cold countries, and others, as the tapir, to warm, but that entire groups, as the sheep on the one hand aud the trogons on the other, seem almost equally dependent on temperature. But when we come to compare the productions of the several continents, we find a set of differenceo in which climate appears to play no part Thus, almost the whole of the warblers USylviida) of Europe and North Asia are absent in similar climates in North America, their place being token by a totally distinct family, the woodwarblers (Mniotiltidcc); the ant-eaters, sloths, and tapirs of tropical America are replaced in tropical Africa by aard\ arks (Oryctcropue), lemurs, and hippopotami; while islands like Borneo and New Guinea, situated in the same ocean not very far apart, and whose climates and physical conditions are, as nearly as possible, identical are yet as radically different in their chief forms of animal life as are remote countries situated respectively in the cold and trujncal zones. It is evident thon, that although climate has o certain amount of influence on the distribution of animal forms, yet geographical conditions aro far inoro important There is reason to believe that the direct action of climate on animal life is far less effective than its indirect action through the limitation of the variety and quantity of vegetable and insect food; whereas geographical isolation has led to diversity of type by its influence on development during successive ages, as pointed ont by Mr Darwin (Origin of Species, 6th ed. p. 81, 83.) It follows that zoological regions, or those primary divisions of the earth characterized by distinct assemblages of animals, will, for the most part, coincide with natural geographical divisions. They do not, however, conform to the actual divisions of our geographies, because these are often political or ethnographical, rather than physical—as in the separation of Europe from Asia. In another case, the coincidence of a mountain chain (the Himalayas) and the plateau of Thibet, with the demarcation of the tropical and temperate zones, forms a zoological division across a continent almost as complete as would be effected by a considerable extent of ocean.

Vertical Distribution of Animals.—Besides the horizontal distribution dependent on the various causes just indicated, the range of animals is more or less determined by the altitude of the land surface above, or its depth below the sea-level. As we ascend lofty mountains, the forms of life change in a manner somewhat analogous to the changes observed in passing from a warm to a cold country. This change is, however, far less observable in animals than in plants; and it is so unequal in its action, and can so frequently be traced to mere change of climate and deficiency of food, that it must rank as a phenomenon of secondary importance. Vertical distribution among animals will be found in most cases to affect species rather than generic or family groups, and to involve in'each case a mass of local details which can hardly be introduced in a general sketch of the wholo subject of distribution. The same remarks apply to the bathymetrical zones of marine life. Many gruups are confined to tidal, or shallow, or deeper waters; but these differences of habit are hardly "geographical," but involve details, suited rather to the special study of individual groups than to such a general outline of the distribution of the animal kingdom as we are here attempting to lay before our readers.

Pouters of Dispersal of Animals.—Animals differ greatly in their powers of dispersal or migration; and this is an important element in determining the causes of their actual distribution. Mammalia as a class are more limited in this respect than birds; because the former have no means of passing over seas and oceans, or, with few exceptions, over lofty mountains or arid deserts, all of which when of moderate width can be easily traversed by many birds. Reptiles in their adult state are almost as restricted in their powers of dispersal as mammals, but most of them being oviparous, their eggs may be floated on drift wood over seas and straits, or even, in rare case3, be carried by birds; whereas the young of mammalia are for some time wholly dependent on their parents. Amphibia and fresh-water fishes have yet another advantage, that many of them can endure great cold, and their ova may sometimes be frozen without injury. Thus floating ice becomes an important agent in their dispersal, and enables us to account for the curious fact that their distribution often differe in a remarkable manner from that of the three higher classes of vertebrates. When we come to insects, we find the power of dispersal (as regards land animals) at a maximum ; for not only can they travel by almost every mode available to other groups, but their small size, low specific gravity, and (in many cases) great tenacity of life, give them altogether

exceptional advantages in this respect They ara easily carried for great distances through the air by gales and storms; and thero is evidence to show that many remote islands have been thus stocked, and that many wide-spread groups owe their extensive range to this cause. Others can float uninjured for many days at sea; while their eggs or larva?, inclosed in crevices of tree-trunks or concealed under bark, may be carried for hundreds, or even thousands of miles by surface currents across ex'ensree. seas (Wallace, Geographical Distribution of Animals, vol. i. pp. 32, 209-2H). The fact, then, that these small creatures have often a more extensive range, and present greater anomalies in their distribution, than larger animals, is only what we might expect; and if wo keep their unusual powers of dispersal ever present to our minds, wo shall be able to account for most of the anomalies they present, and thus bring them under the same general classification of (lie phenomena of distribution which is most serviceable- m studying the history of the higher animals.

But the actual power of dispersal is by no means the only factor in determining the distribution of a species or a group. It is no use to bring a creature to a new country if it cannot live and maintain itself there. Whether it can do so depends upon many causes. It must be able to adapt itself to a different climate, and generally to different physical conditions; it must be able to live upon whatever food it may find in its new abode; and, most important of all, it must bo able to defend itself against new kinds of enemies and to live in successful competition with allied organisms which are already in possession of the soil

Wide-spread and Local Groups.—There is much reason to believe that the lost-mentioned condition is the most difficult for an intruder to fulfil, and that a large proportion of the immigrants which from any cause arrive in a new country, are unable to maintain themselves in it, not because the country itself is not well adapted to their wants, but solely because it is already occupied by other creatures somewhat better adapted to all the surrounding conditions. Hence arise the phenomena of wide-spread or dominant species, and others which are exceedingly local and often rare, that is, consisting of but a small group of individuals. The former are best adapted to the entire environment, and are generally increasing their numbers and area of distribution; the latter are less perfectly adapted, and probably diminishing in numbers and on the road to final extinction. The power of adaptation seems, generally speaking, to be in an inverse ratio to the power of dispersal The larger mammalia and many birds are capable of enduring a great variety of climates, and even of maintaining themselves in many new countries in competition with the native inhabitants. Thus horses and cattle from the Old World have run wild and greatly multiplied in both North and South America, and are probably capable of existing in any country where there is a sufficiency of open uncultivated land. Insects, on the other hand, are often dependent on some one kind of vegetable food, are especially liable to injuries by climate, and unless very numerous would be liable to be at once exterminated by their various enemies.

Carriers which Limit the Distribution of Animals.—These are of many kinds, and affect the several groups in unequal degrees. The nature of the vegetation alone determines the range of a number of animals. Deserts, marshes, open plains, and especially forests, have each their peculiar inhabitants which can hardly stray far beyond their limits. This is particularly the case with the tropical forests, whose perennial foliage and almost perennial succession of flowers and fruits supply the wants of an immense number of peculiar forms of life. These forests are, in fact, the home of .ill that is most characteristic of the tropics, and their limits form the dividing lines between very distinct faunas. Rivers, when very large, also determine the range of many species, but this is probably because their valleys have been once arms of the sea separating districts with somewhat different faunas. Mountains, when rising to a great height in unbroken ranges, form an impassable barrier to many groups; but their geological age is also an important factor, and they are seldom so ancient and so continuous as to form absolute barriers. Climate, whether determined by latitude or by elevation above the sea, is also a very effective barrier, though probably its action is indirect, and 13 determined by its influence on vegetation, and by bringing diverse groups into competition. The limits of the tropical and temperate zones, generally marked out by more or less extensive deserts, form the boundary between regions or sub-regions all round the globe. Oceans are, however, by far the most important barriers; and this is due not only to their great extent and general impassability to land animals, but also to their enormous antiquity, so that for countless ages they have separated the faunas of remote continents from each other.

In accordance with these principles, it is found, that continents separated by the widest and deepest'oceans differ most radically in the entire series of their animals; while those which are less completely separated, or which are only divided by climatal differences or by mountain ranges, ore less unlike in their chief forms of life. Thus are constituted zoological regions, which represent the most permanent geographical features of the globe, and afford us an indication of that permanence in the isolation aud peculiarity of their animal inhabitants.

Zoological Regions.—Although there is some difference of opinion as to the number and limits of the primary divisions of the earth termed regions, the following are now generally admitted to be the most satisfactory. They are nearly identical with those first proposed by Mr P. L. Sclaterin 1857.

L The Palsearctie Region, which includes nil Enrol* to the Azores aud Iceland, all tcmperato Asia from the high Himalayas and west of the Indus, with Japan, and China from Ningpo and to the north of the watershed of tho Yang-tac-kiang; also North Africa and Arabia, to about the line of the tropic of Cancer. This may be popularly called the European region, Europe being the richest and most varied portion of it and containing representative* of all the more important types ; but it must not be forgotten that the region includes a much larger area in Asia, and that there are many peculiar North Asiatic animals.

2. The Ethiopian Region, which includes all Africa south of the tropic of Cancer, as well as the southern part of Arabia, with Madagascar and the adjacent islands. It may be popularly termed the African region.

3. The Oriental region, wliiuli is comparatively small, including India and Ceylon, the Indo-Chinese countries,aiid southern China, and the Malay Archipelago as far as the Philippines, Borneo, and Java. It may be popularly called the South Asiatic or Indian region. , • ,

4. Tho Australian Region, which is composed of the remainder of the Malay Archipelago, Australia, New Zealand, and all the tropical islands of the Pacific,'as far east as the Marquesas and the Low Archipelago.

5. The Neotropical Region, which comprises the whole of South America and the adjacent islands; the West Indies or Antilles, and the tropical parts of Central America and Mexico. It may be well called the South American region.

«. The Nearctic region, which consists of-all temperate and arctic North America, with Greenland, and is thus well described as the North American region.

These six regions, although all of primary importance 'rom their extent, and well marked by their total assemblage of animal forms, vary greatly in their zoological richness, their degree of isolation, and their relationship to each other. The Australian region is the most peculiar and the most isolated, but it is comparatively am ill, and poor in the higher animals. The Neotropical region comes next in

peculiarity and isolation, but it is extensive and excessively rich in all forms of life. The Ethiopian ond Oriental regions are also very rich, but they have much in common. The Palsearctie and Nearctic regions, being wholly temperate, are less rich, and they too have many resemblances to each other; but while the Nearctic region has many groups in common with the Neotropical, the Palsearctie is closely connected with the Oriental and Ethiopian regions. The cause of these various resemblances and differences depends on tho past history of tho earth, and will be better understood when we have sketched the zoological features of each region and the changes they have undergone in the latest geological periods.

I. The 1'alceareiie Region.—This extensive region, though varied in physical aspect, and often covered with luxuriant vegetation, is poor in animal life when compared with the great tropical regions of the Old and New Worlds. This is no doubt due mainly to climate, but also in part to so much of its surface being densely populated and highly cultivated. It contains, however, a number of characteristic and not a few altogether peculiar animal forms. Beginning with the Mammalia, wo have first the sheep and goats with such allied forms as the chamois and saiga-antelope, which are especially characteristic; deer are abundant and varied , the smaller cats, the wolves, the foxes, and the bears abound, with a variety of smaller groups, as weasels, badgers, and some otters. Seals are plentiful on the northern coast, and even in the Black and Caspian Seas; wild horses and asses abound in Asia, as they once did in Europe; there are many peculiar forms of mica, voles, and hamsters; while dormice, squirrels, marmots, hares, and pikas are well-marked features of the region. The insectivorous family of the mules is almost peculiar, as are the curious mole-rats (Spalax). The genera which are peculiar to the Palsearctie region belong to the following families :—to the moles (Talpidat) 7 genera; to the dogs (Canidcc) 1 genus; to the weasels (Muttclidae) 3 genera; to the pandas (JHuridce) 1 genus; to the seals (Phocidae) 1 genus; to the camels (Camelida) 1 genus; to tho deer (Cervidcc) 6 genera; to the hollow-horned ruminants (Bovidce) 7 genera; to the rats (Mitrida) 6 genera; to the mule-rats (Spalacidce) 2 genera; to the Octodontidae, a peculiar group of rat-like animals only found in South America, Abyssinia, aud North Africa, 1 genus.

In birds, the Palsearctie region is pre*-eminent!y rich in thrushes, warblers, titmice, jays and magpies, sparrows, and buntings. It also abounds in grouse, and in its eastern half in magnificent pheasants. Water-birds are plentiful, and its northern districts produce many fine ducks and divers. The following enumeration of the families of which the Palsearctie region possesses peculiar genera will help to give an idea of the characteristic features of its ornithology :—Of the warblers (Sylviida) 15 genera, many of which, however, migrate into tropical Africa and India in winter; of babblers (Timaliida) 1 genus; of reedlings (Panui-idce) 4 genera; of creepers {Certhiidae) 1 genus; of tits (Paridoe) 1 genus; of the crow family (Corrida) 4 genera; of finches and buntings (Fringillidce) 12 genera; of starlings (Sturnidce) 1 genus; of larks (Alaudidie) 2 genera; of sand-grouse (Pteroclidce) 1 genus; of grouse (Tetraonida) 4 genera; of pheasants (Pliasianidce) 5 genera; of vultures (Vullurida) 1 genus; of rails (Rallu{a!) 1 genus; of snipes (Scolopacidce) 4 genera; of coursers (Glarcolidce) 1 genus; of bustards (Otidi<Ue) 1 genus.

Of the remainiug groups less accurate information is obtainable, and their distribution is less generally interesting. Reptiles, being heat-loving animals, are comparatively scarce, yet in the desert regions they are more plentiful and furnish a considerable number of peculiar types, there being two genera of snakes and fonr of lizards not found in any other region. All reptiles diminish rapidly as we go north, and cease befoia we r<"ach the Arctic circle. The common viper reaches C7" N- lat. in Scandinavia, the northern limit of reptiles In (ho region. Amphibia are much moro patient of cold, the common frog ranging to the extreme north of Europe. Thero are no less than 16 peculiar genera of Amphibia, 8 of the tailed and 8 of the tailless group, the most remarkable being the Prottiu, found only in subterranean lakes in Carniola and Carinthia.

Of fresh-water fishes about 20 genera are wholly confined to the region, of which the perches (Pereidce) have 3 genera; the salmons and trout (Salmonida) 3 genera; the carp (Cyprinida) 13 genera; with a peculiar genus aud family (Comephortu) found in Lake Baikal, and another (Teliia) belonging to the CyprinodorUida, in the Atlas Mountains.

Insects are so extensive a class that the barest enumeration of their most remarkable forms would be out of place in such a sketch as this. We can only mention that, although butterflies are not very numerous, yet no less than 15 genera are peculiar to the region. Beetles, however, abound, and the most characteristic Palxarctic group is undoubtedly the Carabida, or predaceous ground-beetles, which are more predominant hero than in any other region, and are also of larger average size—a most unusual circumstance in tho insects of a temperate as compared with those of tropical regions.

Land shells are tolerably numerous both in species and individuals, but are of small size and little beauty as compared with those of warmer countries. Very fow of the genera are peculiar.

The total number of tho generic forms of Vertebrata peculiar to tho Palaearctic region is, as nearly as can be estimated, 138,—a very large number when we consider the general severity of the winter, and the circumstance that along its whole southern margin this region is bounded by tropical lands with no absolute barrier against intermigration. The amount of peculiarity may be even better estimated by the fact that, out of a total of 274 genera of Mammalia and birds inhabiting the region, 87, or somewhat lessthan one-third, are confined to it This mode of estimating the zoological character of a region by genrra, gives a far truer idea than any enumeration of peculiar tpeciet, because the former imply more radical and important differences than the latter.

Subdivisions of the Palaarctic Region.—The general zoological characters here given apply with considerable uniformity to the whole of the Palsearctic region, the similarities being of course greater where climate and physical conditions generally correspond. Thus, even between such remote islands aa Great Britain and Vesso (North Japan) there is a wonderful similarity in the general forms of life, many of onr most familiar birds and insects reappearing at the other extremity of the region under identical or but slightly modified forms. *• Owing perhaps to the great climatal changes tho north temperate zone has undergone in recent geological times, and the vast amount of migration thereby produced, as well as to the absence of any continuous barriers, it is very difficult to mark out with accuracy the zoological subdivisions of this region. Certain broad divisions, depending partly on climate, partly on physical features, and partly on geographical proximity to other regions, may, however, be indicated.

Europe, north of the Pyrenees, Alps, Balkans, and Caucasus, may perhaps be considered as the most typical portion of the Pahearctic region, possessing most of its characteristic features in their full development. It may be termed the European sub-region. South of this comes the Mediterranean sub-region, including South Europe aud North Africa, which wonderfully resemble each other in all their chief forms of animal life, although some few purely African species are found south of the Mediterranean. This sub-region includes also Asia Minor and Persia, with Syria and Northern Arabia. It is chiefly characterized by a number of desert forms, such as gazelles, civets, jerboas, quails, desert-larks, and numerous lizards; and by a number of species which cannot endure the colder climate of the north, as porcupines, monkeys, Ichneumons,

and a host of pccnlinr groups of insects. To this region belong the Atlantic islands from tho Azores to the Canaries, the animal productions of all of them being closely related to those of South Europe or North Africa. It is a curious fact that the remotest of those islands, the Azores, offer less peculiarity in their birds and insects than Madeira and the Canaries, which are so much nearer tho continent; but this is sufficiently explained by the greater prevalence of storms and gales in the moro northern latitude of tho Azores, and helps to prove that aerial currents are the chief means by which these two classes of animals are dispersed. For a discussion of this interesting subject aud its bearing ou the theories of distribution and development, see Wallace, Geographical Distribution of Animals, vol. i. p. 206.

The northern part of Asia differs very little in the main features of its zoology from tho corresponding parts of Europe, but as we approach the northern slopes of tho great plateau of Central Asia many peculiar forms occur, as wild horse, pikas (Lagomys), starlings of the Renus rodocci, and many others. Tho great desert plateaus of Thibet and Mongolia form another subdivision, with many peculiar forms. Here are found the yak, soma peculiar antelopes, with wild sheep and goats, and several peculiar rodents ; and among birds many peculiar tonus of grouse, partridges, and pheasants.

Another well-marked division is formed by the temperate portion of Eastern Asia, comprising Japan, Manchuria, Northern and Central Chinaj with parts of East Thibet and the higher portions of the Himalayas as tar west as Ncpaul. This is a fertile and luxuriant district which receives several tropical forms of life from thr adjoining Oriental region. It is rich in Insectivora and in deer, the deer-like musk being confined to it; it has a peculiar form of wild-dog (Nyctcreutcs), and even several peculiar species of tht monkey tribe. It is also pre-eminently the home of the pheasant tribe, such magnificent birds as tho golden, silver, and Iteeva's pheasants being peculiar to it. It has also a number of showy jays, finches, tits, and warblers ; and its insects present a number of fine tropical-looking species. The Manchnrian sub-region has thus a very beautiful and varied fauna, but tho intermingling of Oriental types, and tho uncertainty of its Bouthem boundary, render it less characteristically Palxarctic than the European sub-regions.

II. The Ethiopian Region.—This region is much lesa extensive than tho lost, but being almost wholly tropical it presents a richer and more varied assemblage of animals. Its southern extremity, although really extra-tropical, is yet so warm and so little subject to extremes of temperature that the growth of vegetation and the corresponding development of animal life are scarcely diminished, and the same may be said of the elevated interior of the continent. As Madagascar is quite isolated and its productions very peculiar, it will be best first to sketch the main features of African zoology, which are tolerably well marked and homogeneous.

The African continent is pre-eminently the country of large Mammalia, It possesses an abundance of elephants, rhinoceroses of several species, giraffes (now peculiar to it), gorillas and baboons—the largest of tho ape tribe, a host of large and remarkable antelopes, tho huge hippopotamus, several species of zebras, wild buffaloes, several remorkablo forms of swine, and an abundance of lions, leopards, and hysenas,—forming together an assemblage of large and highly organized animals such as occur nowhere else npon the globe. There are also many smaller, but very remarkable forms. There are 7 peculiar genera of apes, 3 of lemurs, 5 of Intectivora, 12 of Viverrida, the remarkable Proteles forming a distinct family allied to hyaenas and weasels, 2 of Canidjc, 2 of Miatelidce, 2 of Suidce, 1 of Tragvlida, 12 of Bovidae (antelopes), 18 of various families of Rodents, and the curious aardvark (Oryderopus), forming a distinct family of Edentata.

In birds Africa is not so peculiar, yet it has many remarkable groups. Such are the plantain-eaters (Mumphagida), the colies (Coiiida), the secretary-birds (Serpentariidte), the ground horn-bills, and the guinea-fowl,— all of which are peculiar. It abounds also in peculiar flycatchers, shrikes, sun-birds, weaver-birds, starlings, larks, barbets, grouse, and hawks,—more than half the genera of land-birds being peculiar, and, if we include those of Madagascar, nearly two-thirds.

Reptiles abound, there being three peculiar families of snakes and one of lizards; and there is one peculiar famil;

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