E M 1 E M I 173 example remains at large in the districts that have been fully settled. It is said to have existed also on the islands of Bass s Straits and in Tasmania, but it has been exter minated in both, without, so far as is known, any ornithologist having had the opportunity of determining whether the race inhabiting those localities was specifically identical with that of the mainland or distinct. Next to the Ostrich the largest of existing birds, the common Emeu is an inhabitant of the more open country, feeding on fruits, roots, and herbage, and generally keeping in small companies. The nest is a shallow pit scraped in the ground, and from nine to thirteen eggs, in colour varying from a bluish-green to a dark bottle-green, are laid therein. These are hatched by the cock-bird, the period of incubation lasting from 70 to 80 days. The young at birth are striped longitudinally with dark markings on a light ground. A remarkable structure in Dromceus is a singular opening in the front of the windpipe, communicating with a tracheal p.Hich. This has attracted the attention of several anatomists, and has been well described by Dr Murie (Proc. Zool. Soc. 1867, pp. 405-415). Various conjec tures have been made as to its function, the most probable of which seems to be that it is an organ of sound in the breeding-season, at which time the hen-bird has long been known to utter a remarkably loud booming note. Due convenience being afforded to it, the Emeu thrives well, and readily propagates its kind in Europe. It is the only form of Ratite bird which naturally takes to the water, and examples have been seen voluntarily swimming a wide river. The existence in Australia of a second species of Dromaeus had long been suspected, and Broderip in 1842 stated (Penny Cyclop, xxiii. p. 145) that Mr Gould had even supplied a name (D. y>arvulus) for it ; but there can be little doubt that this suggestion was founded on a mistake. However, in 1859 Mr Bartlett described, under the name of D. irroratus, what has since been generally admitted to be a good species, and it now seems certain that this fills in the western part of Australia the place occupied by the older-known form in the Eastern. It is a more slender bird, and when adult has the feathers barred with white and dark-grey ending in a black spot which has a rufous margin, while those of D. novce-hollandice are of a uniform blackish-grey from the base to near the tip, which is black with a broad subterminal rufous band. Both species have been figured by Mr Sclater from admirable drawings by Mr Wolf (Trans. Zool. Soc. iv. pis. 75, 76), and interesting particulars as to their domestication in England arc given by Mr Harting (Ostriches and Ostrich Farming, pp. 131-174). (A. N.) EMIGRATION, now one of the most constant and orderly movements of human society, must have been one of the earliest, however irregular, of human impulses. It is the act of men, families, tribes, or parts of tribes, leaving the place of their birth with the. view of settling in some other place. They are emigrants in the country they leave, and immigrants in the country they pass into. But this converse nomenclature describes an identical class of persons and the same kind of adventure, more necessary now than ver to be distinguished from migrations within a given terri tory, or the frequent travellings between distant countries in which many engage, whether on purposes of business or pleasure. Emigration is a going out with a design of per manently settling in new seats of residence, labour, trade, nnd society. It is the practical response which mankind have given in all ages to the command to " multiply, and replenish the earth, and subdue it ;". or, in other words, it is a necessary result of the increase of population within a limited though cherished space, and of the appointed destiny of our race to people and develop the world. The natural law of population, though probably the deep underlying force of all emigrations, is not the only force at work in the general movement by which people, and races of people, have migrated from one part of the world to another. Not only famines, which may be said to present tho pressure of population in its intensest form, but wars of official conquest and ambition, religious persecu tions and religious phantasies, civil broils and political re volutions, the discovery of gold and silver mines, the envy of more genial climes and fertile lands than people have been born to, the individual love of change and adventure and pushing one s fortune, have considerable power in pro moting emigrations, apart from the rude pressure of physi cal wants. Famines in India, for example, do not result in much emigration; and yet the Irish famine in 1846-7 led immediately to one of the most remarkable removals of persons and families from one hemisphere to another in modern times. It would be difficult to account by the law of population for the successive immigrations of Saxons, Danes, and Normans into England, or to maintain that it was a force of hunger only which impelled the Northern barbarians to attack the Roman Empire. In the invasion of Turkey in 1877 the Russian soldiers are said to have been surprised at the plenty of the Bulgarian towns and villages, and to have had curious reflections why they should have been led so far afield to battle for the relief of a population so much more comfortably bastowed than themselves. Yet when the Russian soldiers return to their comparatively sterile homes, having seen the abundance of grain and fruits and flowers on the slopes of the Balkans, their accounts will probably only increase the Muscovite passion to penetrate by force of arms into more productive regions than those of Northern Europe and Asia. We must allow, in short, for many causes of emigration, as well as many wrong views of the means by which the advantages of emigration are to be realized. The passage of Scripture which relates what took place between Abraham and Lot in the plains of Bethel, adduced by J. R. M Culloch in the article " Emigration " in the last edition of this work, will always remain a strikingly natural and suggestive picture of the outward movement of society in its primitive elements. There was no want apparently of material resources. " Is not the whole land before thee," were the words of Abraham ; and Lot, lifting up his eyes, saw the plain of Jordan unoccupied and well-watered. But there was strife among the servants, quarrels as to pasturings and waterings, with Canaanites and Perizzites dwelling in the land as an additional element of disorder. The kinsmen could not agree, or adjust their rule ; and separation would be judicious, if not necessary. The narrative exhibits the influence of individualism on human affairs on the affair of emigration as on others. In early times it was found difficult or impossible to make any important progress on the basis of social unity. Nomads taking possession of vacant territory or invading the territory of others, victorious kings carrying whole tribes or nations into captivity, citizens driven out of civilized states by political rage, or . attracted to adjacent lauds by the promised wealth of agriculture or trade, and colonies more or less officially organized in the track of war and conquest, are the pictures we have of emigration in the ancient world. " Many of the emigrants from the Grcok States, as Mr M Culloch wrote in the article above referred to, " consisted of citizens forced hv the violence of contending factions to seek nw settlements m other coivntriox But Greece also sent forth emigrants, impelled by the difficulty of maintaining themselves at home, or allured by the crlovin" descriptions of the comparative abundance they would enjoy in distant lands. Both these classes of emigrants established themselves, for the most part, either in countries with a scanty population, or whose inhabitants were in a decidedly lower state of
civilization. And the greater refinement and ingenuity of the