NATURE STUDY FOR GIRL SCOUTS
FOREWORD
The following section was specially prepared for the Girl Scouts by Mr.
George H. Sherwood, Curator, and Dr. G. Clyde Fisher, Associate Curator,
of the Department of Public Education of the American Museum of Natural
History. All the illustrations used were supplied by the Museum, and the
tests in the various subjects were devised by the same authors.
The American Museum of Natural History in New York conducts special
courses of lectures in all of the branches of Natural History, and
extends a cordial invitation to all Girl Scouts to visit the Department
of Education if wishing help in preparation for their Nature Study
tests.
_Contents_
1. Introduction to Nature Study.
2. Plants: Flowers and Ferns and Trees.
3. Animals: Mammals
Birds
Reptiles
Amphibians
Fishes
Invertebrates
4. Geology.
[Illustration: AN EGRET "ROOKERY" IN SOUTH CAROLINA.
The demand for the nuptial plumes of this bird in the millinery trade
brought it to the verge of extermination. Range: Temperate and tropical
America. Habitat Group in The American Museum of Natural History.]
1. Introduction to Nature Study
_To the solid ground
Of Nature trusts the mind which builds for aye._
--_Wordsworth._
_To understand nature is to gain one of the
greatest resources of life._
--_John Burroughs._
Nature Study means getting acquainted with the multitude of creatures,
great and small, which inhabit the land, the water, and the air, and
with the objects which surround them. Mother Nature has many, many
secrets which she will reveal to sharp eyes and alert minds. It is, of
course, impossible for any one to learn all these secrets, but the
mastering of a few makes it easier to learn others, until finally it
becomes clear that all life is related and that the humblest creature
may be of the greatest importance to the welfare of the highest.
It is for these reasons that the _Girl Scout_ should learn as much as
possible of the Wonders of Nature. This study may begin wherever you
are, but rapid progress will be made by rambles afield and by visits to
the great Natural History Museums. For example, a visit to the
exhibition halls of the American Museum of Natural History in New York
will answer many of your questions about animals you have seen and will
enable you to answer many others for yourself, when you go out into the
country.
Nature Study in its broadest application includes all of the natural
sciences, such as zoology, botany, geology, meteorology, and astronomy.
So, there are many fascinating fields for study and enjoyment, and it
does not matter much where we begin, whether it be Wild Flowers, Trees,
Birds, Butterflies, or Stars.
[Illustration: THE BULLFROG IN ITS NATURAL SURROUNDINGS
See Snake, Turtle and Dragonfly and notice the tongue of the frog.
Habitat Group in Museum of Natural History]
Of the more practical subjects especially suited to the activities of
the Girl Scout are those civic problems which can only be solved by
team-play; that is, by working together. Among these may be mentioned:
The preservation of birds, wild flowers, and forests; control of
mosquitoes, house-flies, rats, weeds; diseases of plants and animals,
including man.
The civic nature of these problems is appreciated when we realize that
it would do little good, for example, for one person to destroy the
breeding-places of mosquitoes on his premises, if his neighbors did not
do likewise about their homes; or for one orchardist to cut out the
blight from his pear-trees or the black-knot from his plum-trees, if his
neighbors did not co-operate with him by ridding their orchards of these
diseases.
These practical questions are so well presented, together with plans for
their solution, in _Civic Biology_, by Clifton F. Hodge and Jean Dawson
(Ginn & Co.), that instead of going into details here, both the _Girl
Scouts_ and their Leaders are referred to this most useful work.
All objects of Nature are either living (organic) or non-living
(inorganic). The non-living bodies include the minerals and rocks. The
living bodies are either plants or animals. Plants may be divided into
two great groups, the flowerless plants and flowering plants. In general
the flowerless plants reproduce by means of spores, like the mushroom
and the ferns, while the flowering plants reproduce by means of seeds.
[Illustration: ROCKY MOUNTAIN GOAT
This animal is really not a goat, but is more nearly related to the
antelopes. Range: The higher mountains from Alaska south to California.
Group in American Museum of Natural History.]
Animals may be separated into two great groups, those without backbones
(invertebrates) like an oyster, a cricket, or an earthworm, and those
with backbones, e.g., a dog, a fish. In this brief study we shall not go
into much detail about invertebrates, but with the backboned animals or
vertebrates we shall go a little further. These may be divided into five
general groups: (1) Fishes; (2) Amphibians, which include frogs, toads,
and salamanders; (3) Reptiles, which include alligators, crocodiles,
turtles, lizards, and snakes; (4) Birds; (5) Mammals.
This simple analysis may be clearly shown by the following diagram:
{_Mammals_
{_Birds_
{_Vertebrates_{_Reptiles_
{ {_Amphibians_
{ {_Fishes_
{_Animals_{
{ {_Invertebrates_
{_Living Bodies_{
{ (_Organic_) { {_Flowering Plants_
_Objects_{ { {_Flowerless Plants_
_of_ {
_Nature_ {_Non-living Bodies_
{ (_Inorganic_)
This classification could be carried further at every point, but this
will be far enough for present purposes. It should be remembered in any
classification that there are no hard and fast lines in Nature. For
example, some creatures are on the border-land between plants and
animals, and again some animals are between the backboned animals and
those without backbones.
[Illustration: GREAT-LEAVED MAGNOLIA
A forest tree with large solitary white flowers. Range: Southern and
Southeastern United States.]
2. Plants
Wild Flowers and Ferns
_Flower in the crannied wall,
I pluck you out of the crannies;
Hold you here, root and all, in my hand.
Little flower--but if I could understand
What you are, root and all, and all in all,
I should know what God and man is._
--_Tennyson._
Do you know the earliest spring flower in your neighborhood? In the
northern United States it is usually found in bloom before all the snow
of winter is gone. In some swamp or along some stream where the snow has
melted away in patches it is possible to find the Skunk Cabbage in
bloom very early in the spring. See how early you can find it. In the
southern United States, one of the earliest spring flowers is the yellow
Jessamine, which twines over bushes and trees thus displaying its
fragrant, golden bells.
[Illustration: TRAILING ARBUTUS
One of our earliest spring flowers, usually growing in patches in sandy
or rocky woods. Range: Eastern United States westward to Michigan.
Photograph by G. Clyde Fisher.]
As the season advances, other flowers appear, and we find the Spring
Beauty, the Trailing Arbutus, the Bloodroot, and the Hepatica. What
delightful associations each of these names brings to our minds! By the
time summer is here we have an entirely different flower-population in
the fields and woods--the Cardinal Flower with its intense red color and
the Pink Lady's-Slipper with its drooping moccasin-shaped lip are to be
found then. In the autumn we have a different group of flowers
still--the Goldenrods, the Asters, and the Fringed Gentian, the season
closing with our latest fall flower, the Witch-hazel.
[Illustration: PINK MOCCASIN-FLOWER
A striking native wild orchid growing in sandy or rocky woods. Range:
Newfoundland to North Carolina westward to Minnesota. Photograph by G.
Clyde Fisher.]
Some flowers and ferns grow best in the shady woods, others in the sunny
fields, some on the rocks and others in the marshes. We soon learn
where to look for our favorites. In taking tramps along the roads,
across the fields, through the woods, and into the swamps, we could
notice along the roadside Bouncing-Bet, Common Yarrow, Dandelion,
Thistles, and Goldenrod; in the fields and meadows, we would see the
Ox-eye Daisy, Black-eyed Susan, Wild Carrot, and the most beautiful fall
flower of the northeastern United States, the Fringed Gentian; in the
woods, Mountain Laurel, Pink Azalea, a number of wild Orchids,
Maidenhair Fern, and Jack-in-the Pulpit; in the marshes, Pink
Rose-mallow, which reminds us of the Hollyhocks of our Grandmother's
garden, Pickerel-weed, Water-lily, and Marsh Marigold.
It is natural to want to know the name of any plant that interests us,
and this is important. As in the subjects of Birds, there are many
helpful books on Flowers and Ferns. Beginners will find "The Flower
Guide," by Chester A. Reed (Doubleday, Page & Co.) to be useful. After a
good start has been made, such books as Gray's _Manual_, or Britton and
Brown's _Illustrated Flora_ should be used.
Our pursuit, however, should not stop with the name of a plant. That is
a mere beginning. Even slight attention will uncover many fascinating
things in the lives of plants. Why cannot a farmer raise a good crop of
clover-seed without the bumble-bees? What devices are there among the
Orchids to bring about cross-pollination? (See "Our Native Orchids," by
William Hamilton Gibson). Examine the flower of the wild Blue Flag, and
see whether you can determine how the bumble-bee cross-pollinates this
plant. Do the Hummingbirds cross-pollinate some flowers? In what plants
is the pollen scattered by the wind? Do these plants produce nectar?
[Illustration: GAILLARDIA OR BLANKET-FLOWER
Daisy family. Range: Hills and plains of western United States and
Canada. Photograph by Albert E. Butler.]
How do the various plants scatter their seeds? How are the Hickory-nuts
and Walnuts scattered? The Dandelion's and Thistle's seeds have
flying-hairs or parachutes and are blown about by the wind. What other
plants can you find whose seeds are scattered in the same way? Can you
discover a plant whose seeds are carried by water? The Witch-hazel
shoots its seeds. What other plants can you find that have explosive
fruits? Cherry-seeds are carried by birds. Mention some other seeds that
are carried in this way. It would take very little observation to learn
how Burdock-burs, Cockle-burs, Stick-tights, Beggar-lice,
Spanish-needles, and such hooked fruits are scattered.
[Illustration: BLACK-EYED SUSAN
A beautiful and abundant flower of the fields. Range: Eastern North
America westward to the Rocky Mountains. Photograph by G. Clyde Fisher.]
Learn the names of the principal noxious weeds of the farm and garden,
and also learn the best methods of combating them.
Learn to know the plants in your vicinity which are used in the making
of drugs.
[Illustration: LOCO-WEED
A poisonous plant which produces loco-disease in cattle, sheep, and
horses that eat it. Range: Plains from Montana to Colorado. Photograph
by Albert E. Butler.]
Learn to know the poisonous plants around your home and summer camp. Are
the following to be found there: Poison Ivy, Poison Sumach, Loco-weed,
Bittersweet (_Salanum Dulcamara_), Black Nightshade, Jimsonweed,
Poke-weed, Poison Hemlock?
[Illustration: SHOWY PRIMROSE
Not a true Primrose, but a member of the Evening Primrose Family. Range:
Prairies of western United States and northern Mexico; also naturalized
farther east. Photograph by Mr. and Mrs. Leo E. Miller.]
Trees
_He who wanders widest lifts
No more of beauty's jealous veils,
Than he who from his doorway sees
The miracle of flowers and trees._
--_Whittier_
The trees of the forest are of two classes, deciduous trees and
evergreen trees. To the former belong those which shed their leaves in
the fall, are bare in the winter, and then grow a new crop of leaves in
the spring, e.g., oaks, elms, maples. The evergreen trees shed their
leaves also, but not all at one time. In fact, they always have a
goodly number of leaves, and are consequently green all the year round,
e.g., pines, spruces, firs.
[Illustration: RHODODENDRON OR GREAT LAUREL
A tall shrub, or sometimes a tree, growing in woods and along streams.
Range: Eastern North America from Nova Scotia to Georgia. Photograph by
Albert E. Butler.]
The uses of wood are so many and various that we can only begin to
mention them. In looking about us we see wood used in building houses,
in making furniture, for railroad ties, and for shoring timbers in
mines. In many country districts wood is used for fuel. And do you
realize that only a short time ago the newspaper which you read this
morning and the book which you now hold in your hand were parts of
growing trees in the forest? Paper is made of wood-pulp, mostly from
Spruce.
[Illustration: CHRISTMAS FERN
An evergreen fern growing in woods and rocky places. Range: Eastern
United States and Canada. Photograph by Mary C. Dickerson.]
Besides the direct uses of wood, we turn to the forest for many
interesting and valuable products, varying in importance from a
balsam-pillow filled with the fragrant leaves or needles of the Balsam
Fir, to turpentine and rosin (naval stores), produced chiefly by the
Long-leaved Pine of the Southeastern States. Spruce gum is obtained from
the Black Spruce and Red Spruce. Canada balsam used in cementing lenses
together in microscopes, telescopes, and the like, comes from the
Balsam Fir. Bark for tanning comes from Oak and Hemlock. The Indians of
the Eastern Woodlands or Great Lakes area made canoes and many other
useful articles of the bark of the Canoe or Paper Birch. Baskets are
made from Willow twigs. Maple sugar comes chiefly from the Sugar Maple.
[Illustration: IN A TURPENTINE GROVE
The long-leaved Pine furnishes most of the turpentine and rosin of
commerce. Range: Virginia to Florida and Texas. Photograph by G. Clyde
Fisher.]
[Illustration: BLACK SUGAR MAPLE
The sap of this tree, as well as the more common Sugar Maple, is the
source of maple sugar. Range: Eastern United States and southeastern
Canada.]
The turpentine industry is the chief one in parts of the South where the
Long-leaved Pine thrives. The United States produces more turpentine and
rosin than any other country in the world. The turpentine is used in
paints and in various arts. The rosin is used in varnish, laundry soap,
etc. These two products come from the sap or "gum" of the pine tree. The
sap is secured by tapping or "boxing" the tree, and then keeping the cut
ducts of the sap-wood open by "chipping" or "pulling," that is, by
putting a new "streak" on the tree. This has to be done once a week from
March 1 to November 1. The sap used to be collected in a "box" or deep
notch cut in the base of the tree, but the modern method is to have it
run into cups made of zinc or of burned clay similar to flower-pots. The
sap is taken to a turpentine still where it is heated over a furnace.
This drives off the turpentine or "spirits" as steam or vapor, which is
condensed to liquid again by passing through the worm of the still
surrounded by cold water. The rosin or resin is left behind.
[Illustration: COMMON FALL MUSHROOM
An excellent article of food growing commonly in old pasture fields.
Range: Temperate and tropical regions all over the world. Photograph by
G. Clyde Fisher.]
The Sugar Maple grows from Florida and Texas northward to Manitoba and
Quebec, but it is only in the northern part of its range that the maple
sugar industry thrives. This delicious food is one of the many that we
learned to utilize from the Indians. The sap is obtained by tapping the
tree in the spring before the leaves come out, the best weather for the
flow of sap being that when it freezes at night and thaws in the
daytime. The sap is boiled down; that is, the water is driven off and
the sugar remains. It takes about three gallons, or a little more, of
sap to make a pound of maple sugar. Three to four pounds of sugar is an
average yield for one tree in a season. Much of the sap, however, is not
boiled down into sugar, but the boiling is stopped while it is in the
form of syrup. If you have ever eaten buckwheat cakes with real maple
syrup you will always esteem the Sugar Maple tree.
The forests perform extremely valuable services for mankind entirely
apart from the products they yield.
First, they prevent erosion, or the washing away of soil by the water
that falls as rain. After the trees have been cut away, very often,
especially upon hillsides, the most productive soil is washed away,
usually clear off of the original owner's farm, and deposited in the
flood-plains or bottoms of creeks and rivers or in river deltas--in
places where it cannot be utilized to any great extent. Thus erosion
causes a tremendous loss to farmers, and it is chiefly due to the
thoughtlessness of the American people in destroying the forests.
Second, and chiefly related to this, is the fact that the floods upon
our rivers, which every year take such heavy toll in property and in
human life, are due to the cutting away of the forests. This allows the
water from rain and melting snow to reach the streams at times faster
than it can be carried off, and so we have a flood. The forest floor,
with its undergrowth and humus, in those localities where the forests
still exist about the headwaters of our rivers, acts like a huge layer
of blotting paper which holds the water back and allows it to escape to
the streams slowly, and so floods are avoided.
Third, and related to the above, is the fact that the water supply of
our cities would be more constant if the forests had not been cut away.
In these cases the summer droughts make much greater the danger from
water-borne diseases.
[Illustration: WESTERN YELLOW PINE
A magnificent tree which furnishes valuable timber. Range: Hills and
mountains of western United States. Photograph by Albert E. Butler.]
[Illustration: ROADS THROUGH THE ASPENS
Range: Northern United States and Canada, south in the Rocky Mountains
to Mexico. Photograph by Albert E. Butler.]
It is only in recent years that the American people have begun to
realize the necessity of the conservation of our forests, and in many
sections much has been done to redeem the criminal thoughtlessness in
destroying our forests and to restore those devastated by forest fires.
Reforestation operations have accomplished a great deal, and the
organization to prevent forest fires emphasizes the old adage that "an
ounce of prevention is worth a pound of cure." Also the people are being
taught correct forestry practices, such as cutting only ripe trees and
allowing the rest to grow, instead of clearing the land entirely, as was
formerly done so universally.
[Illustration: BALD CYPRESS DRAPED WITH SPANISH "MOSS."
This tree is almost entirely hidden by this "moss," which is really a
flowering plant of the Pineapple family. Range: In swamps and along
rivers from Delaware to Florida, west to Texas, north to Missouri and
southern Indiana. Photograph by G. Clyde Fisher.]
The life history of every tree is interesting; how it breathes by means
of its leaves, just as the animals do by means of gills or lungs; how it
manufactures starch by means of the green matter in the leaves; how the
starch is changed to sugar and other substances which are carried to
other parts of the tree in the sap; how the sap flows upward in the
vessels in the sap-wood and downward in the vessels of the inner bark;
how the entire heart-wood of a tree is dead and the only living part is
the sap-wood and the innermost bark.
One of the first things we shall want to know when we get out into the
woods is the name of the tree that interests us. For this purpose the
books given as references under "Trees" will be useful.
[Illustration: TIMBER WOLVES ON THE TRAIL
Closely related to foxes and dogs. Range: Formerly over most of North
America. Habitat Group in American Museum of Natural History.]
[Illustration: BABY OPOSSUMS RIDING ON THEIR MOTHER'S BACK
For the first few weeks after they are born the mother carries her
babies in her pocket; later they ride on her back holding on by clinging
to her fur with their paws and by wrapping their tails about that of
their mother. Range: Middle and Southern States. From Group in American
Museum of Natural History.]
3. ANIMALS
Mammals
Mammals differ from birds in that they have hair instead of feathers,
and that they are first fed upon milk produced by the mother.
Unfortunately the mammals are usually called simply _animals_, but the
latter is obviously too inclusive a term and should not be used in this
way. There is no reason why the name _mammal_ should not be commonly
used, just as _birds_, _reptiles_, _amphibians_, and _fishes_ are used
for the other groups of backboned animals.
[Illustration: NEW YORK WEASEL IN SUMMER PELAGE]
[Illustration: OTTER WITH ITS FAVORITE FOOD
The Otter belongs to the Weasel family, and feeds almost entirely upon
fish. Range: This and related varieties over Northern and Eastern North
America. From Group in American Museum of Natural History.]
In the United States the lowest or most primitive mammal is the Opossum.
The baby Opossums--from six to a dozen of them--are born when very small
and undeveloped and are immediately placed by the mother in an
external pouch, where they continue to grow until they are too large to
get into their mother's pocket; then they frequently ride upon their
mother's back, clinging to her fur with their finger-like toes and
wrapping their tails about their mother's tail. The Opossum is the only
animal in this country the young of which are carried around in the
mother's pocket, and the only one which has a prehensile tail; that is,
one used for coiling around and clinging to branches, and the like. Its
food is various, consisting of both animal and plant material--insects,
young birds, pawpaws, persimmons, etc. In the food devoured the Opossum
probably does more good than harm.
[Illustration: NEW YORK WEASEL IN WINTER
A blood-thirsty cousin of the Otter and the Mink. Range: This and
related species found all over United States and Canada. Group in
American Museum of Natural History.]
[Illustration: RACCOON AT ENTRANCE TO ITS DEN IN A HOLLOW TREE
A near relative of the bears. Note the black face-mark and the ringed
tail. Range: This or a related variety occurs in all parts of United
States. Photograph from American Museum of Natural History.]
In their food habits many mammals are decidedly injurious. Rats,
Weasels, Minks, and Foxes destroy poultry; Wolves and Pumas kill
domestic and game animals; Woodchucks or Groundhogs eat clover and
various garden plants; Moles damage the lawns; Rats, Mice, and Gophers
spoil and devour grain; Mice and Rabbits girdle fruit trees, thus
killing them.
On the other hand, many mammals furnish food; _e. g._, Rabbits, Elk, and
Deer. This was more important in pioneer times than at present. Many
furnish furs used as articles of clothing; _e. g._, Raccoon, Fox,
Muskrat, Mink, Otter, Marten, Mole, New York Weasel and other northern
weasels in their winter coats.
[Illustration: POLAR BEAR
An expert swimmer. Feeds upon seals, fish and other animal food. Range:
Arctic regions of the world. Habitat Group in American Museum of Natural
History.]
Many furs are usually sold under trade names that are entirely different
from the true name of the animal. A list of a few fur-bearing mammals of
the United States having trade names differing from the true names
follows:
_The True Fur_ _The Trade Name_
Dark blended Muskrat Russian Otter
Mink blended Muskrat Natural River Mink
Natural Muskrat[6] River Mink
Natural Jersey Muskrat River Sable
Plucked and Seal-dyed Muskrat Hudson Seal
Plucked and Seal-dyed Muskrat Aleutian Seal
Skunk Black Marten
Striped Skunk Civet Cat
N.Y. Weasel in winter pelage Ermine
[Illustration: SKUNKS--MOTHER AND YOUNG HUNTING FOR GRASSHOPPERS AND
CRICKETS
Noted for its ability to emit a most unpleasant odor when disturbed.
Range: Eastern North America. Portion of Group in American Museum of
Natural History.]
[Illustration: MINK
A cousin of the Weasel and Otter, the Mink feeds upon frogs, crayfish,
mice, bird's eggs, etc. Range: This and closely related forms over most
of United States, Canada, and Alaska. From Group in American Museum of
Natural History.]
A few suggestions for observation or study:
1. What peculiar instinct or habit has the Opossum developed?
2. How does the flight of a Bat differ from that of a Flying Squirrel?
3. Can you notice any peculiarity in the Rabbit's track?
4. Mention three mammals that hibernate.
5. Describe the methods of defense in the following mammals: Armadillo,
Porcupine, Skunk.
6. Why do the front teeth of the Squirrel and the Beaver continue to
grow?
The best way to find the answers to these questions is by actual
observation of the animals, but when this is impossible, the references
given under "Mammals" will be found useful.
[Illustration: RED FOX RETURNING TO ITS YOUNG FROM SOME FARMER'S
HEN-ROOST
The Cross Fox, the Silver Fox, and the Black Fox are color phases of the
Red Fox, and not different species. Range: Northern North America south
to Georgia. Habitat Group in American Museum of Natural History.]
[Illustration: BALD-EAGLE
The American Eagle, the Emblem of our Country. Range: United States]
Birds
_He who takes the first step in ornithology is
ticketed for the whole trip._--_John Burroughs._
[Illustration: A GREBE COLONY IN SASKATCHEWAN
Showing the Western Grebe and the smaller Grebe. Note the young Grebe
riding on its mothers' back. Another parent is covering its eggs
preparatory to leaving the nest. Range of both these species: Western
North America. Habitat Group in the American Museum of Natural History.]
The love of the beautiful seems to be innate; that is, born in us. And
the birds appeal to this in at least two ways: First, on account of the
beauty of their songs, and second, on account of the beauty of their
plumage.
[Illustration: SCREECH OWL
The Screech Owl feeds largely upon mice and other destructive rodents.
Range: Eastern North America.]
Among the birds that have especially beautiful songs are the Thrushes,
which include the Robin and the Bluebird, the finest singer in this
family probably being the Hermit Thrush. In the Southern States there is
no more popular singer among the birds than the Mockingbird. But it
should be remembered that a bird's song cannot be separated from the
associations which it calls up in one's memory. So that the performance
of an ordinary songster may be more pleasing to one than that of some
finer one because of youthful associations.
[Illustration: SAND HILL CRANES IN FLORIDA
Unlike the Herons, these birds fly with neck fully extended. Their loud,
resonant trumpeting is as characteristic as the honking of Wild Geese.
Range: North America. Habitat Group in The American Museum of Natural
History.]
[Illustration: GREAT HORNED OWL
Rabbits constitute a favorite food when available. Poultry and other
birds are also destroyed by this owl. Range: Eastern North America.]
It seems to be a general law of nature that the finest songsters have
the plainest coats.
[Illustration: BROWN PELICANS IN FLORIDA
The Pelicans nest in colonies, and the young feed from the parents'
throats. Range: Gulf coast of U. S. and southward. Habitat Group in The
American Museum of Natural History.]
[Illustration: EGRETS: PARENT BIRDS]
Among the birds that we enjoy on account of their beautiful plumage are
the Egrets, every feather of their coats being as white as snow, and
the plumes of these birds are so beautiful, and human beings have been
so thoughtless that the Egrets have been almost exterminated in order to
supply the millinery trade. These plumes, known as aigrettes, grow on
the backs between the shoulders of both the male and female birds, and
are worn only during the nesting season. The only time during the
nesting season that the plume hunter finds it profitable to hunt these
birds is when the young are in the nest. At any other time the birds
would be so wild that the plume hunter could not easily shoot them. When
the young are in the nest the parental love is so strong that the adult
birds cannot resist the instinct to return to feed the nestlings when
they are begging for food. In this way both the father bird and the
mother bird become an easy prey for the ambushed plume hunter, and there
is but one thing that can happen to the baby Egrets in the nest after
both of their parents have been killed--they starve to death. This is
one of the most cruel phases of the plume trade, and there is no other
way to secure the aigrette plumes of the Egrets than by killing the
adult birds. Fortunately, in the United States it is against the law to
shoot these birds, and it is against the law to import the plumes. Until
recently it has not been illegal to wear these plumes, and the fact that
there are still a few women who adorn their hats with them has
encouraged the illegal and cruel killing of these birds in our country,
or the smuggling in of the plumes from some other country. In the
latter part of 1919 the federal regulations have been interpreted to
make it illegal to possess aigrette plumes, and henceforth the law will
be so enforced. This is the successful culmination of a long fight by
the Audubon Society.
[Illustration: GOLDEN PLOVER
The Golden Plover makes the longest single flight known to be made by
any bird in migration,--that is, 2,500 miles from Nova Scotia across the
open ocean to South America. Range: North and South America.]
[Illustration: BOBOLINK
During the autumn migration this bird is the Reedbird or Ricebird.
Range: North and South America.]
A few other birds of striking plumage are the Bluejay, the Bluebird, the
Baltimore Oriole, the Scarlet Tanager, the Cedar Waxwing, and Red-winged
Blackbird.
Turning from the esthetic value of birds, which depends, among other
things, upon the beauty of their songs and the beauty of other plumage,
we may consider the value of birds in dollars and cents.
[Illustration: WILD TURKEY IN WEST VIRGINIA
Our most magnificent game-bird. Note how much the young resembles the
dead leaves. Range: Eastern United States west to Nebraska and Texas.
Habitat Group in The American Museum of Natural History.]
[Illustration: NORTHERN SHRIKE IMPALING A HOUSE SPARROW UPON A THORN
The habit illustrated here has given the Shrike the name of
Butcher-bird. It is surprising to find a song-bird with the habits of a
bird of prey. Range: Northern North America.]
[Illustration: DUCK HAWKS ON THE PALISADES OF THE HUDSON
The "Noble Peregrine" of falconry carrying a pigeon to its young. Range:
North and South America. Habitat Group in The American Museum of Natural
History.]
Every farmer and gardener must cultivate his crops and fight the weeds
which are always crowding out the plants he is trying to raise, and in
this fight he is helped by a great many birds of various kinds. Among
these are the Mourning Dove, the Bob-White, and members of the Sparrow
family, such as the Goldfinch, the Junco, and the Song Sparrow. In this
country, in the aggregate, these seed-eating birds destroy every year
tons of seeds of the noxious weeds, and are therefore valuable friends
of the gardener and farmer. For more definite data see bulletins
published by the U. S. Department of Agriculture, or "Useful Birds and
Their Protection," by Edward Howe Forbush (Massachusetts Board of
Agriculture).
[Illustration: A KILLDEER FAMILY
This plover is common in meadows, cultivated fields, and about ponds and
lakes. It gets its name from its note. Range: North and South America.]
Thousands of bushels of grain are eaten or spoiled by small mammals,
such as mice, rats, and spermophiles or gophers. To the relief of the
farmer, many birds feed upon these destructive little rodents. The Crow
occasionally captures a mouse, while the Shrikes or Butcher-birds catch
a great many. The Screech Owl feeds largely upon mice. The Red-tailed
Hawk is called the Hen-hawk or Chicken-hawk by most farmers, but this
is very unfair to the bird, for its principal food is mice. In fact,
most of the Hawks and Owls of the United States are really valuable
friends of the farmer because of the injurious rodents which they
devour. (See "_Hawks and Owls of the United States_," by A. K. Fisher.)
[Illustration: STARLING
Introduced 1890 into New York City; since spread over northeastern
states. Western and central Europe, New England and Middle Atlantic
States.]
To be fair, it must be admitted that there are a few exceptions; that
is, that there are a few Hawks and Owls which do more harm than good.
The Sharp-shinned Hawk kills many harmless songbirds and occasionally
young game birds and young chickens. The Cooper's Hawk, which nests
throughout the United States, is a real chicken hawk, and the worst one
in the country. The Duck Hawk, the "Noble Peregrine" of falconry, in
this country feeds largely upon domestic pigeons, but no bird student
would wish to see it exterminated on account of this habit.
There are a number of birds which are valuable friends to all the people
because they are scavengers. The Herring Gull, which is the commonest
gull of the harbors of the United States, and which is also found on
inland lakes and rivers, by feeding upon all kinds of refuse animal and
plant materials makes the waters about our cities more healthful. This
is especially true of the coast cities which dump their garbage into the
waters not far distant. The Turkey Vulture, the Black Vulture or
Carrion-Crow, and the California Condor make the fields and woods of the
country more healthful by devouring the carcasses of animals, and the
first two species eat the offal from slaughter houses and even scraps of
meat from the markets in some of our Southern cities.
[Illustration: COMMON TERN
A close relative of the gulls. Range: Northern Hemisphere, northern
South America and Africa.]
[Illustration: GREAT BLUE HERON
Frequently miscalled Blue "Crane." The long legs indicate that this is a
wading bird. Range: Western Hemisphere.]
The most valuable group of birds from the standpoint of the farmers, the
orchardists, and the gardeners is the insect-eating birds. Among these
are the Wood Pewee, the Phoebe, the Kingbird, and all of the
Flycatchers; the Purple Martin and all of the Swallows; the Nighthawk
and Whip-poor-will. The Yellow-billed and Black-billed Cuckoos and the
Baltimore Oriole feed largely upon tent caterpillars and others
caterpillars which defoliate the fruit and shade trees. The Sparrow
Hawk has been wrongly named, for it eats a thousand times as many
grasshoppers as it does sparrows. The Chickadees, Brown Creepers, and
many of the Warblers feed largely upon insects and insect eggs which
they glean chiefly from the trees. The Rose-breasted Grosbeak and the
Bob-White eat the Colorado potato-beetle. In the West the Franklin's
Gull follows the farmer in the fields and picks up great numbers of
destructive insects.
In learning the value of our feathered friends it is necessary to learn
to know the birds, and in this quest great help can be obtained from
books. Beginners will find the following useful:
"Land Birds East of the Rockies," by Chester A. Reed.
"Water and Game Birds," by Chester A. Reed.
"Western Bird Guide," by Chester A. Reed. (All published by Doubleday,
Page & Co.)
For more advanced students the following are recommended:
"Handbook of Birds of Eastern North America," by Frank M. Chapman (D.
Appleton & Co.).
"Handbook of Birds of Eastern North America," by Florence Merriam Bailey
(Houghton, Mifflin & Co.).
Our study of birds should not stop with the name, because we shall find
many things of interest in the home life of birds, many things that seem
to reflect our own lives. (See "Home Life of Wild Birds," by F. H.
Herrick. G. P. Putnam's Sons.)
If we like to hear birds sing, if we enjoy the beauty of their coats,
and if they are valuable neighbors from the standpoint of dollars and
cents, then it is worth while to consider how we may have more of them
about our homes. Every girl can do a great deal to attract birds.
First, by putting up nesting boxes. Since the people of our country have
destroyed so much of our native forests and undergrowth, have drained so
many of our swamps, and have cultivated so much of the grassy prairie,
many birds have difficulty in finding suitable places to nest. This can
be remedied in the case of birds that nest in cavities, such as the
House Wren, Tree Swallow, Purple Martin, Screech Owl, Chickadee, and
Bluebird, by putting up nesting boxes. For those that nest in shrubbery,
like the Catbird and the Brown Thrasher, shrubs and vines may be planted
so that the desirable tangle may be had.
[Illustration: A MOTHER MALLARD AND HER FAMILY
The Wild Mallard is the original of many of the domesticated ducks.
Range: Northern Hemisphere.]
Second, by putting out bird baths. In this improved country of ours,
there are doubtless large areas in which wild birds have difficulty in
finding suitable places to bathe. Artificial bird baths are more
attractive to birds in the summer time than during cold weather, but
they will be used even in winter if kept free from ice. Do not place a
bird bath so close to a shrub, tree, or building that a house cat may
stalk the birds from behind it. The house cat is probably the worst
enemy of our native songbirds.
Third, by establishing feeding stations, especially in winter when snow
covers the natural food of so many birds. When birds have enough to eat
they rarely suffer severely from the cold.
Fourth, by cooperating with the authorities in seeing that the laws
protecting the birds are enforced.
The Audubon Society has done much effective work along these lines, and
a Girl Scout should join this society, whose headquarters are 1974
Broadway, New York City.
Amphibians
_All nature is so full that that district produces
the greatest variety which is most examined._
--_Gilbert White, Natural History of Selborne._
The group of back-boned animals next above the fishes is the Amphibians,
which includes the frogs, toads, salamanders,[7] and their relatives.
The name "amphibian" refers to two modes of life as shown by most of the
frogs and toads. A good example is the Common Toad, whose eggs are laid
in the water. These eggs hatch out not into toads, but into tadpoles,
which have no legs and which breathe by means of gills, as the fishes
do. They grow rapidly, develop a pair of hind legs and then a pair of
front legs, while the tail and gills are absorbed, all within a little
more than a month from the time the eggs are laid. During this change a
pair of lungs is developed, so that the toads breathe air as human
beings do. The eggs of toads and frogs may be collected in the spring in
ponds, and this remarkable change from the egg through the tadpole stage
to the adult form may be observed in a simple home aquarium. Toads' eggs
may be distinguished from those of frogs by the fact that toads' eggs
are laid in strings, while frogs' eggs are laid in masses.
[Illustration: TOAD
A valuable animal in the garden because of the insects which it eats.
Range: Eastern United States. Photograph by Herbert Lang.]
Every Girl Scout should know the song of the toad. William Hamilton
Gibson says it is "the sweetest sound in nature." (_Sharp Eyes_, p. 54.)
If you do not know it, take a lantern or electric flash-lamp after dark
some evening in the spring at egg-laying time, and go to the edge of
some pond and see the toad sing. Notice how the throat is puffed out
while the note is being produced.
[Illustration: BULLFROG
The largest of our frogs, remarkable for its sonorous bass notes. Range:
Eastern United States westward to Kansas. Photograph by Herbert Lang.]
The belief that warts are caused by handling toads has no foundation in
fact.
The toad is a valuable friend of the gardener, for it feeds upon a great
variety of destructive insects.
The life of our Salamanders is very similar to that of the frogs and
toads. The eggs hatch out into tadpoles, then legs are developed, but
the tail is not absorbed. Unlike the frogs and toads, the Salamander
keeps its tail throughout life, and in some kinds of Salamanders which
spend all of their time in the water, the gills are used throughout
life. Salamanders have various common names, some being called newts,
others water-dogs or mud-puppies. The mud-eel and the Congo "snake" of
the Southern States, and the "hell-bender" of the Ohio valley and south
are all Salamanders. The belief that any of the Salamanders is
poisonous is a myth and has no basis in fact.
[Illustration: SPRING PEEPER
The note of this piping hyla is a welcome sound about the ponds and
swamps in early spring. Range: Eastern United States. Photograph by
Herbert Lang.]
Reptiles
Reptiles include Alligators, Crocodiles, Turtles, Lizards and Snakes. It
is commonly said that reptiles are cold-blooded. This means that the
temperature of their blood varies and is the same as the surrounding
medium. The temperature of an Alligator that has been floating with its
nose out of the water is the same as the surrounding water. The
temperature of a turtle in the winter time is the same as the mud in
which it is buried, while in the summer time it is much higher. What is
true of the reptiles in respect to temperature is also true of
Amphibians and Fishes. However, this is not true of Birds and Mammals,
for these have a uniform temperature so high that they are called
warm-blooded.
[Illustration: GILA MONSTER
So called from the Gila River in Arizona. The only member of the lizard
family known to be venomous except the very similar crust-lizard found
in Mexico. Range: Desert regions of southern Arizona and New Mexico.]
In the United States there is but one species of Alligator and but one
species of Crocodile, both limited to the Southeastern States.
There are about fifty kinds of Turtle and Tortoises in North America,
some of which live on the land and feed largely upon plants, _e. g._,
the Common Box Turtle, found from the New England States to South
Carolina and westward to Kansas, and the Gopher Tortoise of the Southern
States. Others are aquatic, like the Painted Turtles, which are found in
one form or another practically all over the United States.
Many of these reptiles are highly prized as food, _e. g._,
Diamond-backed Terrapin, Soft-shelled Turtle, Snapping Turtle and Gopher
Tortoise.
[Illustration: COMMON BOX TURTLE
Range: Eastern United States]
There are about one hundred species of Lizards in North America, the
greatest number being found in the drier parts of the continent. Of this
whole number only two species are poisonous, and only one of these, the
Gila Monster, is found within the United States, being confined in its
range to desert regions of Southern Arizona and New Mexico.
The Blue-tailed Lizard or Skink, which occurs from Massachusetts to
Florida and westward to Central Texas, is commonly believed to be
poisonous in the Southern States, where it is called the Red-headed
"Scorpion," but this is one of the popular myths still too common among
intelligent people.
The Glass "Snake" of the Central and Southern States is a peculiar
lizard in that it has no legs. That it is able, after being broken to
pieces, to collect itself together again and continue to live is another
old myth.
[Illustration: DIAMOND-BACKED TERRAPIN
Range: Salt marshes of the Atlantic Coast and Gulf of Mexico from
Massachusetts to Texas.]
About a dozen kinds of Horned "Toads" are found in the western portions
of the United States. Although toad-like in the shape of their bodies
and in some of their habits, they are really lizards.
The American Chameleon or "Green" Lizard, which ranges in this country
in the coastal regions from North Carolina to the Rio Grande River, has
a remarkable power of changing the color of its skin through shades of
brown, gray, and green. In fact, it is said to rival or possibly excel
the true chameleons of the Old World.
For treatment of the Snakes see Woodcraft, Section XIII.
FISHES
_"It is not all of fishing to fish."_
[Illustration: PADDLE-FISH
So-called from the paddle-like or spoon-shaped snout. Eggs used for
caviar. Range: The Mississippi River and its tributaries.]
The fishes are the lowest of the true vertebrates or animals with
backbones, and all live in the water. They do not have lungs, but
breathe through gills on the sides of the head. They are cold-blooded
animals; i. e., the temperature of the blood is the same as that of the
water in which they are living. Fishes are found in both fresh and
salt water all over the world and have adapted themselves to many
conditions; for example, certain fishes have lived in caves so long that
they are blind; some live in the coldest water, while others can revel
in the heat of the hot springs.
[Illustration: COMMON CATFISH
The barbels which suggest the whiskers of a cat are responsible for the
name. This fish has no scales. Range: Eastern and Central United
States.]
Many fishes are valuable as food and the fisheries are extensive
industries, in which large sums of money are invested.
There are four great groups of fishes:
1. The sharks and rays, with cartilaginous skeletons.
2. The ganoids of which the sturgeon and garpike are examples, with
heavy plates or scales.
3. The bony fishes--salmon, pickerel, mackerel, cod, halibut, etc.
4. The lung fishes, that live partly in air.
[Illustration: SHOVEL-NOSED STURGEON
This fish is covered with bony plates instead of scales. The roe is made
into caviar. _Range_: Upper and middle Mississippi Valley.]
There are many species of sharks. Among the more common ones in Atlantic
waters are the Smooth Dogfish which have pavement-like teeth; the Sand
Shark with catlike teeth; the Hammerhead Shark with its eyes on stalks.
The near relatives of the sharks are the Skates. The most common
example of the ganoid fish is the sturgeon, which is heavily clad with a
bony armor. Most of the fishes that we find, however, belong to the
third group, i. e., bony fishes. Among the salt-water species, the cod,
the halibut, the mackerel, and the bluefish are especially valuable as
food. Of the salt-water fishes that go up the rivers into fresh water to
breed, the salmon and the shad are widely known. Of a strictly
fresh-water fish, the sunfish and catfish are very common. Among the
game-fish are the trout, bass, pickerel, and salmon.
For those who live in cities, a convenient place to begin the study of
fishes is in the fish-market. Here we may learn to know the common
food-fishes by name, and to know many interesting things about them. If
there is a Public Aquarium or a Natural History Museum in your city, you
can use it in connection with the fish-market. Especially valuable in
Museums are the habitat groups of fishes, that is, those in which the
fishes are shown in their natural surroundings. But, best of all, the
place to study fishes, as is true of all other animals, is out-of-doors
in their native haunts. With your dip-net or hook and line, catch the
fish, and then by the aid of one of the books listed below find out what
its name is. Then, by observation of the fish see what is interesting in
its life-history. Find out where the mother-fish lays her eggs. Does
either parents guard them? Has the fish any natural weapons of defense?
If so, what are they? Does either parent care for the young after they
are hatched? What does the fish feed upon? In what way is the fish
protectively colored? In the study of fishes, an interesting means is
the home aquarium. Any Girl Scout can easily learn how to install and
maintain a balanced aquarium, that is, one in which the water does not
have to be changed and in fact should not be changed. In such an
aquarium one may keep and study a great variety of fishes. Some of our
local fishes, such as young catfish and suckers, will prove fully as
interesting as the goldfish and many other animals besides fishes will
thrive in a small aquarium, such as tadpoles of frogs, toads, and
salamanders, adult water-newts, soft-shelled turtles, snails, and
water-beetles and nymphs of dragon-flies.
[Illustration: HAMMERHEAD SHARK
The eyes are on the ends of blunt stalks, or extensions of the sides of
the head, which suggest the name. Range: All warm seas, north to Cape
Cod.]
[Illustration: A GARDEN UNDER WATER
Starfishes, Crabs and Sea-anemones]
[Illustration: SQUID
Member of same family as Octopus, and is related to the Oyster. Has ink
bag for protection.]
Animals Without Backbones
In general the Invertebrates are animals without a backbone; that is,
they do not have an internal supporting skeleton of bone, as does the
dog or cat. Compared with mammals or birds, they are all small and some
are so very tiny that they can be seen only with a very powerful
microscope. Most of them live in the water or in the mud or sand under
the water. Hence the best place to get acquainted with them is along the
seashore or near some lake or stream.
There are several different groups of Invertebrates and between these
groups there are greater differences of structure than there is between
a horse and a hummingbird. The principal groups are:
1. The Protozoa, or one-celled animals (nearly all microscopic).
2. The Sponges.
3. The Jellyfishes, Sea-anemones, and Corals.
4. Worms of several groups.
5. Starfishes, Sea-urchins, and Sea-cucumbers.
6. Segmented Worms.
7. Crabs, Lobsters, etc.
8. Oysters, Snails, and Octopi.
9. Insects and Spiders.
[Illustration: SNAILS AND THEIR TRACKS ON THE BEACH
--_Photograph by Mary C. Dickerson._]
Seashore Life
Because of their connection with our industries or our food supply, some
of the Invertebrates are familiar to all; for instance, sponges,
corals, starfishes, crabs, shrimps, lobsters, clams, and oysters. Others
are seldom seen unless one takes pains to look for them.
[Illustration: JELLY FISH]
All life comes from pre-existing life. So every animal living to-day has
come from some other living animal and every plant living to-day has
come from some other previously living plant. It is believed that the
first forms of life came from the water. At any rate, the oldest and
lowest forms of life to-day, the Protozoa, are found in the water. As
these are nearly all very minute and can be studied only with a
microscope, they are omitted from the suggested field work.
[Illustration: ANIMALS OF THE WHARF-PILES
Habitat Group in the American Museum of Natural History]
All who have access to the seashore have a wonderful opportunity to
study the Invertebrates. The long stretches of sandy beach, the
sections of shore covered with water-rolled pebbles and stones, even the
steep, jagged cliffs, are all pebbled with these animals of the sea.
Twice every twenty-four hours the sea water creeps slowly up the beach
until high water is reached, and twice every twenty-four hours it
recedes again toward the ocean. It is therefore about twelve hours from
one low water to the next. On a gently sloping beach, the distances
between the high water mark and the low water mark may be many hundreds
of feet, while on a steep beach or a straight cliff this area may be
only a few feet in width. It is this area between the high and low water
marks that is the haunt of many Invertebrates. These are animals that
can live if they are not continually covered with water. Here are the
rock barnacles, the soft clams, crabs of many kinds, beach fleas,
numerous sea worms in their special houses, snails, and hermit crabs.
Others will be found in the pools between the rocks or in the crevices
of the cliffs, which as the tide falls becomes great natural aquaria.
Here will be found hydroids, sea-anemones, starfishes, sea-urchins,
barnacles, mussels. In the shallow water, crabs and shrimps are crawling
along the sandy bottom or are lying concealed in the mud, while schools
of little fishes scoot across the pool. If a fine silk net is drawn
through the water and then emptied into a glass dish a whole new world
of creatures will be revealed--jellyfishes, ctenophores, hydroids, eggs
of fish, tiny copepods, the larvae or young of sea-urchins, starfishes,
or oysters. If an old wharf is near by, examine the posts supporting it.
The pilings seem to be coated with a shaggy mass of seaweed. Scrape some
of this off and put in a dish of water. Sea-spiders, starfishes,
hydroids that look like moss, sea-anemones, many varieties of worms,
mussels and crabs are all living here.
[Illustration: UNDER THE SEA BED
Marine Worms, Whelk, Pecten or Scallop and Periwinkle]
Begin your study of these seashore animals with a stroll along the
beach. Examine the windrows of seawrack or seaweed. Whole troops of
sandhoppers rise ahead of you. Oftentimes animals from distant shores or
deep water will be found. The empty shells have many a story to tell.
The papery egg-cases of the periwinkle remind one of a beautiful
necklace. The air bubbles rising from the sand or mud as the wave
recedes mark the entrance to the burrows of worms. Stamp hard on the
sand. A little fountain of water announces the abode of the soft clam.
Watch the sand at the edges of the rippling water. The mole-crab may be
seen scuttling to cover. In the little hollows between rocks a rock-crab
or a green-crab may be found on guard.
[Illustration: WHELK (FULGUR CANALICULATA) AND EGG-CASES
Common Mollusk Found on Sandy Shores Along the Atlantic Coast of the
United States.]
For collecting in the pools and shallow water a fine-meshed net is
desirable. Many of the animals can be caught and placed in glass dishes
of sea water for close observation.
[Illustration: Group showing a starfish attacking an oyster; soft
shelled clams; hermit crabs; fiddler crabs, etc.]
_A few animals that may be found at the seashore:_
_Rocky Shores_--Hydroids on the rock-weed, rock-barnacles, snails,
amphipods, lobsters, and oysters.
_Sandy Shores_--Worms, in tube houses, mole-crab, sand-hopper,
egg-cases, whelks, shrimps.
_Muddy Shores_--Snails, clams, worms of many varieties, mud-crabs,
hermit-crabs, blue crabs, scallops.
_Wharves and Bridges_ (on the piling)--Sponges, hydroids, sea-anemones,
ascidians, starfishes, sea-urchins, worms.
On the shores of lakes, ponds, and streams will also be found many
invertebrates.
[Illustration: HUMMINGBIRD MOTH
Range: Eastern North America. The larvae or caterpillars of this moth
feed upon virburnum, snowberry and hawthorn.]
[Illustration: SEVENTEEN-YEAR CICADA OR SEVENTEEN-YEAR "LOCUST"
Range: Eastern United States. Pupae emerging from the ground. Detail
from Group in the American Museum of Natural History.]
Insects play an important part in Nature's activities. From the point of
view of man some are beneficial and some are destructive. In the former
group may be mentioned the Dragonflies which feed upon mosquitoes, the
Cochineal insects of Mexico, which furnish a dye-stuff, the Lady-bird
beetles, which in the larval stage feed upon plant lice; the scale
insects of India, which furnish shellac; the Bumblebees, which
cross-pollinate the clover, and the Wasps, which fertilize the figs. Dr.
Lutz says that the manna which fed the Children of Israel was honeydew
secreted by a scale insect, and that it is still eaten.
[Illustration: SEVENTEEN-YEAR CICADA OR SEVENTEEN-YEAR "LOCUST"
Range: Eastern United States. The pupa climbing tree trunk. Then it
bursts its horny outer skin and crawls out an adult.]
The Silkworm and the Honey-bee have been domesticated since prehistoric
times, the former supplying a valuable fiber for clothing and the latter
an important article of food.
Among the injurious insects a few may be mentioned: the House Fly or
Filth Fly, which may carry disease germs on its feet to the food that we
eat; the mosquitoes, which transmit yellow fever and malaria, the rat
flea, which carries bubonic plague; the weevils, which destroy rice,
beans, chestnuts, etc., and the plant lice, or aphids, which, by sucking
the juices from ornamental and food plants, are among the most
destructive of all insects.
There are so many insects in the world that we cannot hope to learn of
them all, even if we wanted to do so, but most of us wish to know the
names of those that attract our attention, and to know what they do that
is important or interesting. There are approximately 400,000 species or
kinds of insects known in the world; that is, about three times as many
as there are species or kinds of all the rest of the animals in the
world put together. This fact should not hinder us from making a start
and becoming familiar with the interesting habits of a few of the
insects about us.
The eggs of the Monarch Butterfly may be collected upon the milkweed and
brought in, so that the whole life history or metamorphosis of this
beautiful insect, from the egg through the larva or caterpillar stage
and the pupa or chrysalis stage to the adult butterfly, may be watched.
The larvae or caterpillar must be supplied daily with fresh milkweed
leaves. Other butterflies and moths and many other insects may be reared
in the same way by supplying the larvae with suitable food. If we should
find a caterpillar feeding upon the leaves of a maple tree we should
continue to feed it maple leaves if we wish to rear it. Silkworms will
eat the leaves of Osage-orange, but they seem to prefer mulberry leaves.
Cocoons of moths may be easily collected in winter after the leaves have
fallen, and brought in and kept in a cool place until spring when the
coming out of the adult moths will be an occurrence of absorbing
interest.
[Illustration: "A GATHERING OF MONARCHS"
Monarch Butterflies resting during migration. The Monarch ranges all
over North and South America and it migrates like the birds. Photograph
of group in American Museum of Natural History.]
The spiders, although not insects, are interesting little animals. See
how many types of webs you can find. Mention a few insects which you
know to be preyed upon by spiders. Mention one insect that catches
spiders and stores them away as food for its young.
[Illustration: TRACKS OF THE GLACIER
North America at the time of the maximum stage of the Great Ice Age,
showing area covered by ice. (After Chamberlin and Salisbury).
Photograph used by courtesy of Henry Holt & Co.]
[Illustration: THE KING OF THE NORTHLANDS]
GEOLOGY
_Finds tongues in trees, books in the running brooks,
Sermons in stones, and good in everything._
--_Shakespeare, As You Like It._
The Structure and History of the Earth
There is nothing eternal about the earth except eternal change, some one
has said. It requires only a little looking about us to see that this is
true. The earth is not as it was in the past. Every shower of rain
changes or modifies its surface. And many other and some very great
changes have occurred during the past few millions of years. During one
age, the coal was formed of plants that grew luxuriantly on the earth's
surface. At one period in the development of the earth there were many
kinds of invertebrate animals, but no animals with backbones. Later, the
vertebrates appeared. At one time the whole Mississippi Valley was under
the water of the sea. ("The Story of Our Continent," by N. S. Shaler.
Ginn & Co.). These statements suggest just a few of the things that have
been going on in the history of the earth. By the study of Geology we
can learn much more about it, and we should supplement our study of
books with the more important actual observation of conditions
out-of-doors. To those living in that part of North America, which is
shaded in the map on page 451, the easiest and most natural approach to
the subject of the structure and history of the earth is by studying the
effects of the continental glacier which formerly moved down over this
region.
Tracks of the Glacier
When we see the foot-prints of an animal in the mud or in the snow, we
are sure that an animal has passed that way at some previous time. Those
who live in Canada or northern United States (See map page 451) can be
just as sure that a great glacier or ice-sheet formerly moved down over
northern North America, by the tracks it has left. Although it is
estimated by geologists that between 10,000 and 40,000 years have
elapsed since the Great Ice Age, these tracks or evidences can still be
seen by any one who lives in this region or who can visit it. The
principal ones are: (1) Boulders or Lost Rocks which were brought down
by this glacier; (2) The Glacial Drift or Boulder Clay which covers
nearly all of the glaciated region; (3) Scratches on the bed-rock which
show the direction the glacier moved.
Notice in the field the size and shape of the glacial boulders, where
they are found, evidence of the place where the glacier melted off
(terminal moraine). Do these boulders increase or decrease in size as we
go south over the glaciated area? Can you discover any place where they
can be traced back in their native ledge? Present-day glaciers, like the
Muir Glacier in Alaska, can be seen transporting boulders and drift just
as this great prehistoric ice-sheet must have done.
The drift which consists of clay mixed with pebbles, cobblestones, and
boulders, varies greatly in depth. In some places there is none, while
at St. Paris, Ohio, it is 550 feet deep. It probably averages 100 feet
thick or less.
In your locality note the depth of the drifts in cuts made naturally by
creeks and rivers or those made artificially for railroads. Oil-wells
furnish evidence on this point. Collect a few good examples of scratched
or glaciated pebbles or cobblestones which are abundant in the drift.
These were scratched while frozen in the bottom of the glacier and
pushed along on the bed-rock under the weight of the ice above.
Collect ten different kinds of rock from the glacial boulders and
drift,--there are more than one hundred kinds to be found,--and with the
aid of some such book as "Rocks and Rock Minerals," by Louis V. Pirsson
(John Wiley & Sons) or "Common Minerals and Rocks," by Wm. O. Crosby (D.
C. Heath & Co.) try to identify them.
All soil is composed of disintegrated or decayed rock. And it has been
observed that the soil of northern North America is foreign to the
bed-rock. Therefore it must have been transported from some other place.
The glacier did this huge piece of work. The soil of southern United
States contains no boulders or cobblestones and has been formed by the
disintegration and decay of rocks in place.
Observe glacial scratches and grooves on the bed-rock, those on Kelley's
Island in Lake Erie are famous.
Agassiz was the first to realize that it was a glacier that did this
stupendous piece of work, and this conception or discovery greatly added
to his fame. It is now easy for us to find the evidences and to enjoy
their interpretation.
In fact, the Greenland ice-sheet is a remnant of this prehistoric
continental glacier.
FOOTNOTES:
[6] Muskrat fur is now also sold under its true name.
[7] Unfortunately in the Southern States there is an entirely different
animal commonly called a "Salamander" which is in reality a
pocket-gopher of the group of mammals.