From the middle to the last of April there are several big w_Appletons' Popular Science Monthly, April 1899 Volume LIV, No. 6, April 1899

migration that bring many of the summer residents as well as some

transient species, forerunning the greater waves that are to follow in

May. On certain warm April days the barn and the bank swallows appear,

and the chimney swifts are seen scurrying to and fro above the trees

and house tops. These are genuine signs of the coming summer, for

swallows and swifts feed only on the minute gnats and other ephemera

that develop under conditions of warm temperature. Whoever knows of a

martin box that year after year is visited by its colony has an

unfailing source of delight at this time in watching the lovely birds.

The martins are very prompt in their arrival, rarely coming before the

1st of April nor later than the 10th. We are aware for the first time

that the house wren has come back by the voluble song that greets us

some morning from the branches just beyond our window--a song that

only the lover of his own rooftree can fully appreciate, for the

wren's chant, more than any other bird song, seems to voice the home

instinct in a man. By the last week of April the woods are fast

closing up their vistas in a rich profusion of unfolding leafage. The

umbrellalike leaves of the May apple are scattered everywhere through

the woods and fields, forming conspicuous patches of green. During

this last week of the month a few straggling thrushes make their

appearance--the hermit thrush with its russet tail, the veery, and the

wood thrush. The first two are transients, flitting through the

underwoods or rustling among fallen leaves in search of their insect

food. To hear the incomparable matins and vespers of the hermit one

must follow to the bird's breeding range on the wooded slopes of the

Appalachians or farther into the deep recesses of the Canadian

forests. The wood thrush breeds with us, and the melody of its notes

adds a peculiar charm to our groves and woodlands that would leave an

unfilled blank in the choir if the bird were a transient like the

hermit or the veery.

From the 1st to the 10th of May a succession of bird waves comes from

the south of such vast proportions as to the number of individuals and

variety of species that all the previous migratory waves seem

insignificant in comparison. It is the flood tide of the migration,

bringing with it the host of warblers, vireos, orioles, tanagers, and

thrushes that suddenly make our woods almost tropical in the variety

of richly colored species and strange bird notes. It would take a

volume to describe the wood warblers, sylvan nymphs of such bizarre

color patterns and dainty forms that one is fain to imagine himself in

the heart of some wondrous forest of a far-away land. Their curious

dry notes, each different in its kind and expression, yet all of the

same insectlike quality; their quick, active motions, now twisting

head downward around the branches, prying into every nook and cranny

in their eager search for food, or fluttering about the clusters of

leaves, add to the strange effect. Their names, too, are richly

stimulative to the color sense--the black-throated green, the

black-throated blue, the chestnut-sided, the bay-breasted, the black

and yellow, the cerulean, the Blackburnian, the blue-winged yellow,

the golden-winged, the blue-yellow-backed or parula warbler, and the

Maryland yellow-throat are each suggestive of a wealth of coloring.

Others have names that carry us to southern realms, like the myrtle

and the palm warblers; and others again tell of curious habits, as the

worm-eating warbler, the hooded fly-catching warbler, and the black

and white creeping warbler that scrambles about the tree trunks like a

true creeper. There is nothing in all the year quite like the May

woods. Then, if never again, you can step from your dooryard into an

enchanted forest. The light yellowish effects of new green in the

feathery masses of the oak catkins and the fresh, unfolding leafage of

the forest trees are a rich feast to the eyes. Against this wealth of

green the dogwood spreads its snow-white masses of bloom. In sunlit

spaces of greenness the scarlet flash of a tanager, the rich blue

coloring of the indigo bird, newly arrived from its winter quarters in

South America, and the glimpse of a rose-breasted grosbeak among the

high tree tops are strangely suggestive of a tropical forest. The ear,

too, is charmed with a multitude of curious notes. The weird cries of

the great-crested flycatcher among the topmost branches, and the loud

chant of the ovenbird with its rising cadence coming from farther

depths of the wood are two of the most characteristic bird voices of

the May woodlands. If one would have the famous song of the mocking

bird in this sylvan carnival he has only to loiter in the nearest

grove to hear the wonderful performance of the catbird. The catbird is

the real harbinger of summer. He is familiar throughout the

countryside, liked or disliked according to the dispositions of folks,

but when he appears amid the May-day throng every one knows that

summer has come. As a countryman once said to me: "You can't place any

dependence on the robin--it may snow the very day he comes; but a

catbird never makes a mistake--it's summer with him for sure."

The passing on of the great warbler waves to the north and the ending

of the migration likewise mean the passing of the spring. It is summer

any time after the 15th of May, or, to be more accurate, after the

last of the migratory warblers, thrushes, and tanagers have passed

beyond our woods. To a New-Englander summer will come a little later,

nearer the true almanac date of June 1st. To a dweller in Virginia the

last of April is the passing of spring and the advent of summer.

Some ten or more years ago several enthusiastic ornithologists living

in the neighborhood of Philadelphia began keeping records of the times

of arrival of the different species of birds, and at the same time

noted the conditions of temperature in relation to the abundance of

individuals. After several years of these observations they were able

to see clearly that these bird waves were directly related to the

waves of rising temperature marking the advent of warm spells of

weather. One of the most significant facts deduced from these

observations was the remarkable regularity in the first appearance of

certain species. For example, the Baltimore oriole in eight years of

observation never arrived before the 1st of May, and only twice later

than the 4th--viz., once on the fifth and once on the 7th. The list on

the opposite page shows the date of first arrivals extending over a

period of eight years, from 1885 to 1892.[10]

-------------------+----------+----------+----------+----------+

| 1885. | 1886. | 1887. | 1888. |

-------------------+----------+----------+----------+----------|

Flicker | April 10 | Mar. 24 | Mar. 26 | Mar. 30 |

Hummingbird | April 29 | May 12 | May 12 | May 14 |

Kingbird | May 6 | May 11 | May 7 | May 6 |

Crested flycatcher | May 2 | May 12 | May 3 | May 1 |

Pewee | April 3 | Mar. 20 | Mar. 21 | Mar. 22 |

Wood pewee | May 6 | May 15 | April 30 | May 13 |

blackbird | Mar. 4 | Feb. 19 | Feb. 19 | Feb. 21 |

Meadow lark | ....... | Feb. 10 | Mar. 19 | Mar. 21 |

Baltimore oriole | May 5 | May 4 | May 2 | May 2 |

Purple grackle | Mar. 16 | Mar. 7 | Feb. 19 | Feb. 21 |

Indigo bird | May 16 | May 11 | May 7 | May 12 |

Scarlet tanager | May 9 | May 12 | May 5 | May 8 |

Red-eyed vireo | May 7 | May 11 | May 4 | April 29 |

Yellow warbler | May 6 | May 4 | May 2 | May 5 |

green warbler | May 2 | May 11 | May 5 | April 26 |

Chat | May 2 | May 12 | May 5 | May 5 |

Redstart | May 2 | May 4 | May 3 | May 1 |

Catbird | May 2 | May 4 | May 3 | May 5 |

Wood thrush | May 2 | May 1 | May 1 | May 1 |

Veery | ....... | May 11 | April 25 | May 3 |

Robin | Mar. 7 | Mar. 10 | Feb. 28 | Feb. 19 |

Bluebird | Mar. 18 | ....... | Feb. 17 | Feb. 21 |

-------------------+----------+----------+----------+----------+

-------------------+----------+----------+----------+----------

| 1889. | 1890. | 1891. | 1892.

-------------------+----------+----------+----------+----------

Flicker | Mar. 28 | Mar. 26 | Mar. 30 | April 2

Chimney swift | April 15 | April 22 | April 16 | April 27

Hummingbird | ....... | May 7 | May 11 | .......

Kingbird | May 6 | May 14 | May 1 | May 4

Crested flycatcher | May 8 | May 1 | April 30 | May 3

Pewee | Mar. 27 | Mar. 27 | Mar. 31 | April 3

Wood pewee | May 12 | May 14 | May 6 | May 17

Red-winged | | | |

blackbird | Mar. 13 | Mar. 12 | Feb. 25 | Mar. 9

Meadow lark | Mar. 14 | Mar. 12 | Feb. 23 | Mar. 17

Baltimore oriole | May 7 | May 1 | May 1 | May 3

Purple grackle | Mar. 2 | Feb. 13 | Feb. 18 | Mar. 6

Chipping sparrow | Mar. 29 | April 8 | April 13 | April 4

Field sparrow | Mar. 29 | Mar. 13 | Mar. 15 | Mar. 26

Chewink | April 11 | May 1 | April 18 | April 24

Indigo bird | May 12 | May 10 | May 8 | May 10

Scarlet tanager | May 9 | May 4 | April 28 | May 3

Barn swallow | April 22 | April 19 | April 19 | April 24

Red-eyed vireo | May 5 | April 30 | May 2 | May 3

Black-and-white | | | |

warbler | April 20 | April 30 | April 24 | May 1

Yellow warbler | May 11 | May 1 | May 8 | May 4

Myrtle warbler | April 20 | April 27 | April 18 | April 7

Black-throated | | | |

green warbler | May 5 | May 2 | April 19 | April 30

Ovenbird | May 3 | May 3 | April 29 | April 30

Maryland | | | |

yellow-throat | May 6 | April 30 | May 1 | May 3

Chat | May 11 | May 5 | May 1 | May 3

Redstart | May 4 | May 3 | April 29 | April 30

Catbird | May 5 | May 5 | May 4 | April 30

Brown thrasher | April 22 | April 30 | April 19 | April 30

House wren | April 14 | April 30 | April 19 | May 5

Wood thrush | May 3 | April 30 | April 23 | May 2

Veery | May 6 | May 2 | April 28 | May 4

Hermit thrush | April 10 | April 13 | April 12 | April 3

Robin | Mar. 7 | Feb. 26 | Feb. 24 | Mar. 9

Bluebird | Mar. 8 | Feb. 23 | Feb. 17 | Mar. 9

-------------------+----------+----------+----------+---------

Another fact of great interest which bears on the south-to-north

movement of migrating birds, and which these observations very clearly

brought out, was the earlier appearance of individuals of various

species at points nearer the river, the first arrival of the same

species at points back from the river being, in many instances,

several days later. The first report of the arrival of a given species

usually came from a low, marshy tract of land immediately bordering

the western shore of the Delaware. The second report came from a

locality several miles back of the eastern shore of the river, but

situated in the low plain of the river valley and within tide-water

limits. The third report came from a place some miles back from the

river on the uplands, but near the head of a stream emptying into the

Delaware from the west. The last two places to report arrivals were

situated farther up the river and some distance back from it. All this

confirms the general idea that in migrating most, if not all, of the

various land birds follow river valleys and invade the upland

districts, lying back from either side, by way of the smaller

tributaries.

The fact of greatest importance resulting from these observations was

that relating to temperature. It was found that there was always a

marked increase in the number of individuals of a given species

following a warm wave of temperature as marked by a decided rise of

the thermometer. The following graphic representation, based on the

abundance from day to day of three common and easily observed

species--the brown thrasher, chipping sparrow, and flicker--affords an

interesting illustration of the relative movements of the two waves.

It will be understood that the numbers in the extreme left-hand column

refer to the relative abundance of individuals of the three species

collectively. The inside column refers to temperature. The period of

observation was twenty days, as shown by the line across the top of

the figure.[11]

[Illustration: A, migration; B, temperature.]

The advent of spring is marked by the northward progression of the

isotherm of 42.8° F., which is the initial temperature required to

awaken the dormant reproductive and germinating activities in animals

and plants. With the gradual invasion of the United States, from the

south northward, by temperatures above this, there passes over the

different regions the ever-old but ever-new panorama of the spring

with its opening blossoms, its unfolding green, and its waves of

migrating birds. The restlessness produced by the periodic development

of the reproductive function under the stimulus of increased

temperature causes the highly organized bird life to spread out from

its winter quarters, wherever those may be, and follow the zone of new

green that steadily widens northward with its increase of food supply

in the form of myriads of insects. The comparative regularity in the

recurrence of this phenomenon year after year is attested by the

observations just noted. Each species has a certain, definite

physiological relation to temperature, and its migratory movement

toward the breeding ground is determined by the movement of the

isotherm of this temperature. Just as warm a spell of weather may

occur in early April as in the first week of May, but it does not

represent the permanent summer rise; and the majority of the warblers,

the catbird, the tanager, the rose-breasted grosbeak, the two species

of oriole, the vireos, and the kingbird, are rarely if ever seen in

abundance in the Delaware Valley before the 1st of May. The migratory

movement of such species is as regular as any other periodic

phenomenon in Nature.

It is hard to realize the enormous multitude of birds that form a

so-called "wave." During the whole period of migration there is a

general northward movement of all the migratory species, but under the

influence of warm spells of weather this more or less uniform movement

rises into a vast wavelike sweep of birds. These bird waves, as

already noted, _follow_ the rise of temperature appearing at any given

locality about a day or two after the first day of the warm spell.

Many species of land birds migrate at night--such, for example, as the

orioles, tanagers, warblers, vireos, wrens, the majority of the

finches, the woodpeckers, and the thrushes, excepting the robin.

During the passing of one of the May waves the darkness overhead is

alive with flying birds. One may stand for hours at a time and hear

the incessant chirping and twittering of hundreds of birds calling to

one another through the night as though to keep from getting

separated. The great mass of individuals are probably guided by these

call notes.

The usually accepted notion that birds migrate from south to north in

traveling to their breeding grounds is largely true of shore birds and

waterfowl, but among many of the species of land birds conditions of

topography tend to deflect a direct northward movement. The Atlantic

coast plain, reaching up into southern New Jersey, and the Mississippi

basin, each offers a broad south-to-north highway for birds leaving

the Gulf shores of the United States on their northward journey in the

spring. A great majority of species find in the wilderness of the

Appalachian highland, from the Catskills to Georgia, breeding grounds

quite as well adapted to their needs as the forests of Maine and

Canada. Large numbers of birds, according to their regional relations,

will constantly turn from the Atlantic coast plain up the numerous

rivers, which become great highways of migration, leading to the

highlands. The northward movement has thus a large westerly deflection

on the Atlantic slope of the middle United States. It is also quite

certain that many birds winter in favorable localities on the Atlantic

coast plain much farther north than is generally supposed. This is

especially true of the holly thickets among the coastwise sand dunes

of southern New Jersey and the cedar swamps and pine barrens in the

vicinity of Cape May. Many of the finches, the marsh wrens,

red-winged blackbirds, meadow larks, thrashers, and myrtle warblers

are frequently seen in these localities through the winter. I spent

one first day of February some years ago among the dunes below

Atlantic City, N. J. At Philadelphia that morning it was bleak winter

weather, but two hours later we found ourselves in a warm expanse of

sunlight on the seaward beaches. The balmy air was filled with bird

notes, and the holly thickets and bay bushes fairly swarmed with

myrtle warblers. It seems to be a fact that many birds thus make

comparatively short migratory movements between the seacoast plain and

the mountains, up and down the river valleys.

The phenomenon of the migrating bird has always appealed in a

wonderful manner to the human mind. The guiding geographical sense

that all animals, and wild animals and birds in particular, possess is

peculiarly attractive to men of civilized society, because they have

largely lost this same natural instinct of direction, and now look

upon it in wonderment. Birds have very sure landmarks; their senses

are keen for noting features of topography. They undoubtedly know the

Potomac, the Susquehanna, the Delaware, the Hudson, and the

Connecticut, and never confuse one with another. They know to which

side the sea lies and that the rivers flow down from a wild, wooded

region where there are plenty of food and the best possible places to

raise their young. All these facts get fixed in their brains. The

bird's brain-cell structure is built on these lines and is only

waiting to get the impressions of the first migratory experience. They

keep in with one another, follow their chirpings in the night, learn

to tell the Hudson from the Delaware, or where this or that stretch of

woodland lies, just as they learned when first out of the nest how to

tell good from bad sorts of food, or how to find their way about the

home woods, and that an owl or a fox was an undesirable acquaintance.

In the fall migration the young birds follow the older ones in the

general movement southward, and are often belated, showing that the

impulse to leave their birthplaces is forced upon them, rather from

necessity than choice, and is not the well-developed instinct

impressed by former experience which their elders seem to possess. The

old birds who have bred and reared these young ones set the example of

early departure which the birds of the year through inexperience are

tardy in appreciating. The habit waits upon experience.

Each year, from midwinter, when the first warmth of advancing sunlight

calls to the sleeping life, on to the first fervid heat of the

reproductive summer, we have the joyous pageant of the spring. This

steady waxing of the new light appealed to the pagan mind of western

Europe with a far deeper sense than the modern mind can appreciate. To

our rude ancestors it was the goddess Eástre, bountiful in her gift

of warmth and the magic of reproductive life, that each year came with

the light to drive away the frost giants. And with the goddess, whom

we still love to picture as a maiden tripping lightly through the

budding groves in her wind-blown garments, came the birds. It was the

cuckoo that brought the summer with "daisies pied and violets blue,"

and to-day, when its voice is heard for the first time in the year,

every one knows that summer has come again to the hedgerows of England

and the lands of the Rhine. So with us across the Atlantic, summer

comes when the catbird first pours out its babel of sweet notes in

green woodland ways and the tangled nooks of old gardens.

FOOTNOTES:

[10] The Birds of Eastern Pennsylvania and New Jersey. Prepared under

the direction of the Delaware Valley Ornithological Club. By Witmer

Stone. Philadelphia, 1894.

[11] Stone. The Birds of Eastern Pennsylvania and New Jersey.

GUESSING, AS INFLUENCED BY NUMBER PREFERENCES.

BY F. B. DRESSLAR.

About two years ago a certain progressive clothing company of Los

Angeles, California, procured a very large squash--so large, indeed,

as to attract much attention. This they placed uncut in a window of

their place of business, and advertised that they would give one

hundred dollars in gold to the one guessing the number of seeds it

contained. In case two or more persons guessed the correct number, the

money was to be divided equally among them. The only prerequisite for

an opportunity to guess was that the one wishing to guess should walk

inside and register his name, address, and his guess in the notebook

kept for that purpose.

The result of this offer was that 7,700 people registered guesses, and

but three of these guessed 811, the number of seeds which the squash

contained.

It occurred to me that a study of these guesses would reveal some

interesting number preferences, if any existed, for the conditions

were unusually favorable for calling forth naïve and spontaneous

results, there being no way of approximating the number of seeds by

calculation, and very little or no definite experience upon which to

rely for guidance. It seemed probable, therefore, that the guesses

would cover a wide range, and by reason of this furnish evidence of

whatever number preference might exist. It is undoubtedly safe to

assume, too, that the guesses made were honest attempts to state as

nearly as possible best judgments under conditions given; but even if

some of the guesses were more or less facetiously made, the data would

be equally valuable for the main purpose in hand.

According to the theory of probability, had there been no preference

at all for certain digits or certain combinations of digits within

the limits of the guesses, one figure would occur about as often as

another in units' or tens' place. It was argued, therefore, that any

marked or persistent variation from such regularity in such a great

number of cases would reveal what might be termed an unconscious

preference for such numbers or digits for these places.

The purpose of this study, then, was to determine whether or not there

existed in the popular mind, under the conditions offered, any such

preferences.

After the very arduous and tedious task of collating and classifying

all the guesses for men and women separately had been done, the

following facts appeared:

In the first place, marked preference is shown for certain digits both

for units' and tens' places. This statement is based on a study of the

6,863 guesses falling below one thousand. Of these, 4,238 were made by

men and 2,625 were made by women. By tabulations of the digits used in

units' place by both men and women, the following facts have been

determined: 800 used 9, while but 374 used 8; 1,070 used 7, and 443

preferred 6; 881 used 5, and only 295 preferred 4; 862 chose 3, while

331 used 2; 577 ended with 1, while 1,230 preferred 0 as the last

figure.

A tabulation of the figures used in tens' place shows, save in the

case of 2 and 3, where 2 is used oftener than 3, the same curious

preferences, but in a much less marked degree. To go into detail, 850

chose 9 for tens' place, while 559 took 8; 907 used 7, while only 637

selected 6; 748 took 5, while only 536 used 4; 601 used 3, and 634

chose 2; 728 used 1, as against 872 who used 0.

Were it not that the selections here in the main correspond with the

preferences shown in units' place, the significance of these figures

would be much less important; but the evidence here can not wholly be

ignored when taken in connection with the facts obtained in the

preferences shown in the case of the figures occupying units' place.

We are enabled, then, as a result of the study of these guesses, to

say that under the conditions offered, aside from a preference of 0

over 1 to end the numbers selected, digits representing odd numbers

are conspicuously preferred to those representing even numbers. How

far this will hold under other conditions can not now be stated, but

the facts here observed are of such a nature as to suggest the

possibility of an habitual tendency in this direction. However,

further investigations can alone determine whether or not this bias

for certain numbers is potent in a general way.

The curve on the next page, exhibiting the results noted above, shows

at a glance the marked and persistent preference for the odd numbers.

It will be noticed that of the digits preferred, 7 surpasses any of

the others. Not only, then, do we tend to select an odd number for

units' place when the guess ranges between one and a thousand, but of

these digits 7 is much preferred. In connection with this fact one

immediately recalls all he has heard about 7 as a sacred number, and

its professed significance in the so-called "occult sciences." I think

one is warranted in saying from an introspective point of view that

there is a shadow of superstition present in all attempts at pure

guessing. There appears to be some unexpressed feeling of lucky

numbers or some mental easement when one unreasoned position is taken

rather than any other.

[Illustration: CHOICE OF DIGITS IN TENS' AND UNITS' PLACES (MEN AND

WOMEN).

Vertical distance shows the number of times the figure on the

horizontal line immediately below was used.]

It is impossible on the evidence furnished by this study to give more

than hints at the probable reason for the preference here indicated.

But it is worth while to glance backward to earlier conditions, when

the scientific attitude toward all the facts of life and mind was far

more subordinated to supernatural interpretations than it is to-day.

In this way we may catch a thread which still binds us to habits

formed in the indefinite past.

Appletons' Popular Science Monthly, April 1899 Volume LIV, No. 6, April 1899 · 第 6 / 18 段

From the middle to the last of April there are several big waves of