forms which from time to time have been recorded, and which, blown off from their native shore, find in the masses of sea-weed, uprooted trees, and portions of wreck constantly approaching our coasts through the agency of the Gulf-stream, that means of rest and recruitment which finally enables a few of them to reach a welcome though far distant haven. A remarkable degree of capriciousness, which to me has always appeared mysterious, occurs in the choice of localities affected by certain of our migrants: thus the pied flycatcher will not rest until it has reached the middle and northern counties of England, while the nightingale almost restricts its visits to the southern, eastern, and central ones, never favouring Cornwall with its presence, and but rarely going into Devonshire or Wales, or further north than Yorkshire or Durham. Again, some species, exemplified in many of the plovers and sandpipers, make our islands but a halting-place, pausing for rest only on their way to unknown and probably far distant regions.

"The mysterious law or laws which govern migration must always be regarded by the naturalist with the utmost interest. Within our own islands hardly a month passes by without the movement of some species occurring to remind us of the existence of such a principle. In the early spring, before the wheatear, that earliest of our visitors from the sunny south, has arrived, the fieldfare and redwing, which during the winter have peopled our hedgerows and fields, the geese, ducks and numerous wading-birds which have been frequenting our broads and rivers, have, in obedience to Nature's prompting, commenced a movement northward, en route for localities better suited, by the quietude and by the nature of the food found there, for the propagation and rearing of their progeny; then, as the rays of the life-inspiring sun strike upon our earth with daily increasing strength, we begin to welcome in quick succession those little feathered arrivals which make the spring and early summer seasons of so much enjoyment and anticipation to all true lovers of Nature. March, besides the wheatear, brings us the chiffchaff and the sand martin; April's earliest days herald in the swallow, wryneck, and martin; by the middle of that month the nightingale has made its appearance, together with a host of other sylvan species; soon after, the cuckoo and landrail arrive; and on the joyous first of May the latest of all comers, the swift, the nightjar and flycatcher may be looked for. A pause of a few weeks follows; and, reproduction having been accomplished, then commences, as it were, the ebb of the great tide of migration. The swift, which, as we have seen, was one of the latest to arrive, is the first to depart; then the landrail makes good its retreat to the more southern country of Africa; other kinds follow in succession, all hastening to make their escape before such changes of climate and natural conditions have set in as would prove fatal to their existence, either on account of the lowering of the temperature or the cessation of suitable food. By the end of September, the great mass have departed, and only

a scanty remnant are to be met with. With this same ebb the autumnal months bring to our sight again strings of grallatorial and natatorial birds, urged by similar causes from the northern regions back towards the south in search of that food and aquatic life which the icy hand of winter had already begun to grudge them and their progeny in their summer location. To follow the sun appears to be the course of true migration; but the promptings of instinct which lead the swallow and many other species to quit our shores, after a brief sojourn, for Africa, or those which lead the fieldfare and the redwing to quit the Norwegian 'fjelds' for our cultivated lands, must surely be connected in some way with, if they have not for their sole object, the provision of food and climate suitable to the species."-P. 3.

Mr. Gould has some very truthful and appropriate observations on the difference in punctuality between immigration and emigration, the regularity of arrivals manifestly exceeding that of departures; but I cannot find that he throws any additional light on this most interesting subject, and it is well worth deep and attentive study: it is a matter of constant astonishment to me that ornithologists devote so much thought, ingenuity and research to the changing of a Latin name, and so little, so infinitesimally small a portion of either, to observing the habits and actions of the living bird. This taste or fashion now prevails to such an extent that the use of scientific names must inevitably be abandoned altogether before many years have passed over our heads, and each country must adopt its own vernacular names, and thus shut itself up in a mantle, so to speak, of its own ignorance. But let us proceed to Mr. Gould's exposition of the facts of partial migration.

"Besides the regular migration of certain species, a remarkable shifting of locality occurs with others, not only in our own, but in many other parts of the world, the cause of which is totally unknown. Starlings are now very abundant in Cornwall, and missel thrushes in Scotland-in which they were formerly not to be seen. Such interchanges of locality are doubtless occasionally due to alterations in the face of the country: but this was not the cause in the case of Cornwall; for no county can have undergone less alteration; as it was in the days of Julius Cæsar so it is now, unless we except the operations of mining, which naturally only affect the surface of a district to a small extent. The sudden appearance of Pallas's sand grouse (Syrrhaptes paradoxus) in our islands and on various parts of the Continent, in 1859-60, must be in the recollection of every one. This irruption of a strange bird from the distant country of Siberia, perhaps from China, was very astonishing; and it well illustrates my meaning, which may be further exemplified by the mention of two similar occurrences in Australia. In the

year 1839 the whole of the southern and eastern portions of that country was suddenly visited by millions of the little grass parrakeet (Melopsittacus undulatus); and a year or two later swarms of a species of waterhen (Tribonyx ventralis) spread themselves like a cloud over the Swan-River district, destroying fields of corn and garden-produce and committing ravages unheard of before; and both the species have kept their hold until the present day, but of course in much smaller numbers. Although not necessarily bearing upon the preceding remarks, it may be here mentioned that young birds appear to wander further from their native homes during the first autumn or year of their existence than they do afterwards, going out, as it were, to see the world before settling down for the proper business of their lives; hence, doubtless, it is that the young of so many of the rarer northern species (eagles, gulls, divers, &c.) are found further to the south than the old birds."-Page 7.

The observation that the last remark does not necessarily bear on the subject of partial migration, is a very true one: equally truthful is the statement that young birds go further in any given direction than the old ones. I have often observed this on a limited scale among our noteworthy birds of whatever species; thus we read, in the pages of the 'Zoologist' or the columns of the 'Field,' of the slaughter of a golden eagle, a whitetailed eagle, an osprey, a peregrine, &c., in some out-of-the-way and therefore unexpected locality, and we invariably, or almost invariably, find the announcement accompanied by the words "a bird of the year," or "in immature plumage," or "nestling plumage," or some similar explanation that it was not a mature and adult bird travelling for its own pleasure or on its own business. I deduce from long-continued observation of birds, whether perfectly at liberty, as hawks or robin redbreasts; in a state of half-liberty, as pigeons, doves, and bedcherry gahs; or in more strict confinement, as canaries, that parent birds will allow none of their children to remain near the family seat (as we may consider the nesting-place) after they are able to provide for themselves. This seems all but a universal law of Nature, and of course tends to many manifest results; such, for instance, is the leaving to the parents the means of sustenance which they had always enjoyed; and such also is the dispersion of the species over a larger area, and thus preventing that crowding on a limited space which is always prejudicial to the welfare of a species. Although this fact is so well known to the preservers of game, yet with strange pertinacity they adhere to the

extermination of " vermin," as they call eagles and hawks, until the race of game-birds is unnaturally crowded, and, as a consequence, is sensibly depauperated. Nature, ever wiser than man, makes equal provision for the preservation of all her tribes; she designs that each shall possess that rood of ground necessary for its maintenance, and so she entrusts the parents with the necessary duty of driving the young ones away and bidding them shift for themselves. Hence the fact that young birds wander farther south or farther north, as the case may be, than the old ones, and thus also it happens that the rare birds recorded in the 'Zoologist' are in immature plumage. I could gladly have enlarged on this interesting topic; but my readers will prefer hearing Mr. Gould, who thus continues:

"Although in the foregoing remarks I have used the terms migrant and migratory in their ordinary acceptation, it will be as well before quitting the subject of migration to place before my readers what I consider should be the strict meaning of the word 'migrant.' The country a bird resorts to for the propagation of its species should be regarded as its true habitat: thus the swallows and others, although they pass only half the year in the British Islands, are really not migrants in the same sense of the term as that in which we should so regard the fieldfare and redwing, who, although resident with us during the winter, retire to Norway and other northern regions for the purpose of breeding, and who are impelled to visit our country solely to obtain the food necessary for their existence. But whilst regarding the species visiting us from the north during the winter months, such as the woodcock, ducks, fieldfares, redwings, &c., as true migrants only, it must be recollected that the swallow, chiffchaff, cuckoo, &c., species leaving us at the same portion of the year, are migrants so far as the countries they respectively winter in are concerned."-Page 8.

On the subject of acclimatizing species or transplanting them from one region to another, much difference of opinion prevails, and Mr. Gould has done wisely to give it his attentive consideration: his conclusions are evidently opposed to those in the mind of every adventurer, that we have only to tether an animal to our own doorpost, in whatever continent or clime we may be pleased to settle, and it will thrive there. Let those who think so look plainly at fact. Have we utilized the zebra, the most beautiful of all quadrupeds? He would fetch some hundreds of pounds in Britain without difficulty, yet after attempting his introduction for two thousand years we give it up in despair. Nature has laws which she refuses to

abandon to our bidding; she says, take the rabbit of New Zealand and welcome, but do not bring the zebra to England; and yet the transit is easy in both cases, and so in hundreds of others.

"Man has frequently been induced to try his hand at the introduction of certain species, the acquisition of which he has considered desirable; such attempts have generally proved futile; Nature having adapted each for a certain locality, the climate and the condition of the country must be altered and rendered fit for the reception of either bird or quadruped before there is the slightest chance of their successful naturalization. Many persons have been desirous of establishing the North-American prairie hen (Cupidonia Cupido) on our moors, and the Ortyx virginianus, or American partridge, in our fields and coverts; but what good would be affected thereby? The prairie hen would but displace a better breed, the common grouse; and the little partridge would be no improvement upon our familiar species. There is no fear, however, that this will ever be accomplished; and the sooner such fallacies are ended the better. It would be far wiser were the efforts of our well-meaning patrons of acclimatization directed rather to that interchange of blood among the same species which is essential to the maintenance of a healthy stock. I am sure it is allimportant with regard to our birds, particularly those that are stationary. It is well known that species that have lived long on an island without a sufficient interchange will diminish both in size and brilliancy of tints; and hence, perhaps, may be explained the smaller size and more subdued colouring of many of our birds, compared with continental examples. The blackcock of Norway and Switzerland will be found to have the tone of its plumage more intensified than those inhabiting Scotland, the black being unmistakably of a darker hue, and the gloss of its feathers more resplendent. The Norwegian ptarmigan, too, is of a purer white compared with our own bird, while its full summer dress is much darker. So, again, the longtailed tit (Mecistura caudata) of Norway and Denmark differs in having a white head, while that of Great Britain has the crown and face dark or obscurely striped; and the cole tit (Parus ater) of Belgium in having the back gray, instead of the slight olive tint seen in British examples. To make such differences, however, grounds for specific distinction, as has in some cases been done, is in my opinion playing with science. That the drier and more rarefied air of the Continent, coupled with the more direct influence of the solar rays, contributes to cause these slight differences, seems to me highly probable; and I am strengthened in this view by noting that among such groups as the Trochilidae, or humming-birds of America, some of the richest and finest colours are seen in species that frequent lofty situations.-P. 15. On the subject of pheasant breeding Mr. Gould touches very slightly, and fails to throw much light thereon: he writes of the

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