The cause of the nocturnal singing of birds that do not go abroad during the night, and are strictly diurnal in all their other habits, has never been rationally explained. It is natural that the whippoorwill, which is a nocturnal bird, should sing during his hours of wakefulness and activity, and we may explain why ducks and geese, and other social birds, should utter their alarm-notes when they meet with any midnight disturbance. The crowing of a cock bears still more analogy to the song of birds; for it is certainly not a note of alarm. This domestic bird might therefore be considered a nocturnal songster, though we do not hear him at evening twilight. The cock sings his matins, but not his vespers. He crows at the earliest dawn and at midnight when he is wakened by the light of the moon, and by artificial light. Many birds are accustomed to prolong their notes after sunset to a late hour, and become silent only to begin anew at the earliest daybreak. But the habit of singing in the night is peculiar to a small number of birds, and the cause of it is a curious subject of inquiry.

By what means are they qualified to endure such extreme watchfulness, singing and providing for their offspring during the day, then becoming wakeful and musical during the night? Why do they take pleasure in singing when no one will come in answer to their call? Have they their worship like religious beings; and are their midnight lays but the fervent outpouring of their devotions? Do they rejoice like the clouds in the presence of the moon, hailing her beams as a pleasant relief from the darkness that has surrounded them? Or, in the silence of the night, are their songs but responses to the sounds of the trees, when they bow their heads and shake their rustling leaves to the wind? When they listen to the streamlet that makes audible melody in the hush of night, do they not answer to it from their leafy perch?

And when the moth flies hummingly through the recesses of the wood, and the beetle winds his horn, what are the notes of the birds but cheerful counterparts to those sounds that break sweetly upon the quiet of their slumbers ?

Wilson remarks that the hunters in the Southern States, when setting out on an excursion by night, as soon as they hear the mocking-bird, know that the moon is rising. He quotes a writer who supposes that it may be fear that operates upon the birds when they perceive the owls flitting among the trees, and that they sing as a timid person whistles in a lonely place to quiet their fears. But if such be the case, Nature has implanted in them an instinct that might lead to their destruction. Fear would instinctively prompt them to be quiet, if they heard the stirring of owls; for this feeling is not expressed by musical notes, but by notes of alarm, or by silence. The moonlight may be the most frequent exciting cause of nocturnal singing; but it is not true that birds always wait for the rising of the moon; and if it were so, the question still occurs, why a few species only should be thus affected.

Since philosophy cannot explain this instinct, let fancy come to our aid, as when men vainly seek from reason an explanation of the mysteries of religion they humbly submit to the guidance of faith. With fancy for our interpreter we may suppose that Nature has adapted the works of creation to our moral as well as our physical wants; and while she has instituted the night as a time of general rest, she has provided means that shall soften the gloomy effects of darkness. The birds, which are the harbingers of all rural delights, are hence made to sing during twilight; and when they cease, the nocturnal songsters become vocal, bearing pleasant sensations to the sleepless, and by their lulling melodies prepare us to be keenly susceptible to all agreeable emotions.

CHANGES IN THE HABITS OF BIRDS.

BIRDS acquire new habits as certain changes take place upon the surface of the country that create a necessity for using different modes of sheltering and protecting their young. Singing-birds frequent in greatest numbers our half-cultivated lands and the woods adjoining them. It may therefore be inferred that as the country grows older and is more extensively cleared and cultivated, the numbers of our songsters will increase, and it is not improbable that their vocal powers may improve. It may be true that for many years after the first settlement of this country there were but few singing-birds and that they have multiplied with the cultivation of the soil. At that time, though the same species existed here and were musical, their numbers were so small that they were not universally heard. Hence early travellers were led to believe that American birds were generally silent.

By a little observation we should soon be convinced that the primitive forest contains but few songsters. There you find crows, jays, woodpeckers, and other noisy birds in great numbers; and you occasionally hear the notes of the sylvias and solitary thrushes. But not until you are in the vicinity of farms and other cultivated lands are your ears saluted by a full band of feathered musicians. The bobolinks are not seen in a forest, and are unfrequent in the wild pastures or meadows which were their primitive resorts. At the present day they have left their early habitats, and seek the cultivated grass-lands, that afford them a more abundant supply of

insect-food, with which they feed their young. They build upon the ground in the grass, and their nests are exposed in great numbers by the scythe of the mower, if he begins haymaking early in the season.

These birds, as well as robins, before America was settled by the Europeans, and when the greater part of the country was a wilderness, must have been comparatively few. Though the bobolink consumes great quantities of rice after the young are fledged and the whole family have departed, it is not the rice-fields which have made its species more numerous, but the increased abundance of insect food in the North, where they breed, — an increase consequent upon the increased amount of tillage. The robins are dependent entirely upon insect food, and must have multiplied in greater proportion than the bobolinks. There are probably thousands of both species at the present day to as many hundreds that existed at the discovery of America. Many other small birds, such as the song-sparrow and the linnet, have increased nearly in the same ratio with the progress of agriculture and the settlement of the country.

It

Domestication blunts the original instincts of animals. and renders birds partially indifferent to colors. changes their plumage as well as their instincts. In proportion to the length of time any species has been domesticated, it is unsafe to depend on the correctness of our observation of their instincts with respect to colors. All the gallinaceous birds, except the common hen, lay speckled eggs. It is probable that during the thousands of ages since the latter was domesticated her eggs have lost their original marking and have become white. As great a change has happened in their plumage, while the more recently domesticated birds, like the turkey and guineahen, retain more nearly their original markings. After domestication birds no longer require to be protected from

the sight of their enemies by the hues of their plumage. Their natural predisposition to be marked only by a certain combination of hues is weakened. Being entirely in the power and under the protection of man, color is of no service to them, as in their natural and wild state.

Mr. S. P. Fowler communicated to the Essex Institute an essay containing some important facts concerning the changes in the habits of some of our own birds. He says: "The Baltimore oriole still constructs her nest after the old pattern, but has learned to weave it with materials furnished by civilization. I have a whole nest of this kind, made wholly from materials swept out of a milliner's shop, woven and interlaced with ribbons and laces, including a threaded needle." He has noticed for several years a change in the habits of our crow-blackbirds, and thinks they are becoming domesticated, like the rooks of England. This change, in his opinion, has been produced by planting the white pine in cultivated grounds; for wherever a group of pines has attained the height of thirty feet, they are visited by these birds for breeding, even in proximity to our populous villages. He states that the purple finches have followed the evergreen trees that have been planted in our enclosures, though a few years since they were to be seen chiefly in our cedar groves. They have grown more numerous, and breed in his grounds on the branches of the spruce, feeding early in the season upon the flower-buds of the elm or upon those of the pear-tree.

From the same communication I gather the following facts, slightly abridging his statements. He remarks that the swallows have suffered more changes than any other birds of our vicinity. The barn-swallows long since left their ancient breeding-places, the overhanging cliffs of rocks, and have sought buildings erected by man; the chimney-swallow has deserted the hollow sycamore for