Chapter XL: Part III: Plant Life (10)

_Ah! on Thanksgiving day, when from East and from West,
From North and from South come the pilgrim and guest,
When the gray-haired New-Englander sees round his board
The old broken lines of affection restored,
When the care-wearied man seeks his mother once more,
And the worn matron smiles where the girl smiled before,
What moistens the lip and brightens the eye?
What calls back the past, like the rich Pumpkin pie?_

_Oh, fruit loved of boyhood! the old days recalling,
When wood-grapes were purpling and brown nuts were falling
When wild, ugly faces we carved in its skin,
Glaring out through the dark with a candle within!
When we laughed round the corn-heap, with hearts all in tune,
Our chair a broad pumpkin--our lantern the moon,
Telling tales of the fairy who travelled like steam,
In a pumpkin-shell coach, with two rats for her team!_
--J. G. WHITTIER.

FLOWERLESS-PLANT STUDY

FERNS

Many interesting things about ferns may be taught to the young child, but the more careful study of these plants is better adapted to the pupils in the higher grades, and is one of the wide-open doors that leads directly from nature-study to systematic science. While the pupils are studying the different forms in which ferns bear their fruit, they can make collections of all the ferns of the locality. Since ferns are easily pressed and are beautiful objects when mounted on white paper, the making of a fern herbarium is a delightful pastime; or leaf-prints may be made which give beautiful results (see page 734); but, better perhaps, than either collections or prints, are pencil or water-color drawings with details of the fruiting organs enlarged. Such a portfolio is not only a thing of beauty but the close observation needed for drawing brings much knowledge to the artist.

_References._--Our Ferns in Their Haunts, W. N. Clute, (of greatest value to teachers because it gives much of fern literature); How to Know the Ferns, Parsons; Ferns, Waters; New England Ferns, Eastman.

THE CHRISTMAS FERN

_Teacher’s Story_

“_No shivering frond that shuns the blast sways on its slender
chaffy stem;
Full veined and lusty green it stands, of all the wintry
woods the gem._”
--W. N. CLUTE.

The rootstock of the fern is an humble example of “rising on stepping stones of our dead selves,” this being almost literally true of the tree-ferns. The rootstock which is a stem and not a root--has, like other stems, a growing tip from which, each year, it sends up into the world several beautiful green fronds, and numerous rootlets down into the earth. These graceful fronds rejoice the world and our eyes for the summer, and make glad the one who, in winter, loves to wander often in the woods to inquire after the welfare of his many friends during their period of sleeping and waking. These fronds, after giving their message of winter cheer, and after the following summer has made the whole woodland green and the young fronds are growing thriftily from the tip of the rootstock, die down, and in midsummer we can find the old fronds lying sere and brown, with broken stipes, just back of the new fern clump; if we examine the rootstock we can detect behind them, remains of the stems of the fronds of year before last; and still farther behind we may trace all the stems of fronds which gladdened the world three years ago. Thus we learn that this rootstock may have been creeping on an inch or so each season for many years, always busy with the present and giving no heed to its dead past. One of the chief differences between our ferns and the tree-ferns of the tropics, which we often see in greenhouses, is that in the tree-fern the rootstock rises in the air instead of creeping on, or below, the surface of the ground. This upright rootstock of the tree-fern also bears fronds at its tip, and its old fronds gradually die down, leaving it rough below its crown of green plumes.

Photo by Verne Morton.]

The Christmas fern has its green stipe, or petiole, and its rachis, or midrib, more or less covered with ragged, brownish scales, which give it an unkempt appearance. Its pinnæ, or leaflets, are individually very pretty; in color they are dark, shining green, lance-shaped, with a pointed lobe or ear at the base projecting upward. The edges of the pinnæ are delicately toothed, each point armed with a little spine, and the veins are fine, straight and free to the margin; the lower pinnæ often have the earlike lobe completely severed.

_1. Fertile leaflet of Christmas fern showing indusia and
spore-cases._ _2. An indusium and spore-cases, enlarged._ _3.
A spore-case, enlarged._ _4. A spore-case discharging spores,
enlarged._
]

In studying a fertile fern from above, we notice that about a dozen pairs of the pinnæ near the tip are narrowed and roughened and are more distinctly toothed on the margins. Examining them underneath, we find on each a double row of circular raised dots which are the fruit-dots, or sori; there is a row between the midrib and margin on each side, and also a double row extending up into the point at the base. Early in the season these spots look like pale blisters, later they turn pale brown, each blister having a depression at its center; by the middle of June, masses of tiny globules, not larger than pin points, push out from beneath the margin of these dots. The blisterlike membrane is simply a cover for the growing spores, and is called the _indusium_; by July it shrivels into an irregular scroll, still clinging to the pinnule by its depressed center; and by this time the profusion of tiny globules covers the entire under side of the pinna like a brown fuzz. If we scrape off some of this fuzz and examine it with a lens, we can see that it consists of numberless little globules, each with a stem to attach it to the leaf; these are the spore-cases, or sporangia, each globule being packed full of spores which, even through the lens, look like yellowish powder. But each particle of this dust has its own structure and contains in its heart the living fern-substance.

Photo by Verne Morton.]

Not all the fronds of the fern clump bear these fruit-dots. The ones we select for decoration are usually the sterile fronds, for the fertile ones are not so graceful, and many ignorant people think the brown spore-cases are a fungus. The Christmas fern being evergreen and very firm in texture, is much used in holiday decoration, hence its common name, which is more easily remembered than _Polystichum acrostichoides_, which is its real name. It loves to grow in well-shaded woodlands, liking better the trees which shed their leaves than the evergreens; it is indeed well-adapted to thrive in damp, cold shade; it is rarely found on slopes which face the south, and sunshine kills it.

LESSON CLXXIII

THE CHRISTMAS FERN

_Leading thought_--The fern has a creeping underground stem called the rootstock, which pushes forward and sends up fresh fronds each year. Some of the fronds of the Christmas fern bear spores on the lower surface of the terminal pinnæ.

_Method_--This lesson should be given during the latter part of May, when the fruit-dots are still green. Take up a fern and transplant it, in a dish of moss, in the schoolroom, and later plant it in some convenient shady place. The pupils should sketch the fertile frond from the upper side so as to fix in their minds the contracted pinnæ of the tip; one of the lower pinnæ should be drawn in detail, showing the serrate edge, the ear and the venation. The teacher should use the following terms constantly and insistently, so as to make the fern nomenclature a part of the school vocabulary, and thus fit the pupils for using fern manuals.

A _frond_ is all of the fern which grows on one stem from the rootstock; the _blade_ is that portion which bears leaflets; the _stipe_ is the stem or petiole; the _rachis_ is the midrib and is a continuation of the stipe; the _pinnule_ is a leaflet of the last division; the _pinna_ is a chief division of the midrib or rachis, when the fern is compound; the _sori_ are the fruit-dots; the _indusium_ is the membrane covering the fruiting organs; the _sporangia_ are the tiny brown globules, and are the spore-cases; the _spores_ make up the fine dust which comes from the spore-cases. It would be well to make a diagram on the blackboard of the fern with its parts named, so that the pupils may consult it while studying ferns.

_Observations_--1. Study a stump of the Christmas ferns. Are there any withered fronds? Where do they join the rootstock? Do the green fronds come from the same place on the rootstock as the withered ones? Do the green ferns come from near the tip of the rootstock? Can you find the growing tip of the rootstock? Can you trace back and find where the fronds of last year and year before last grew? Does that part of the rootstock seem alive now? Can you find the true root of the fern?

2. Take a frond of the Christmas fern. Is the stem, or stipe, and the midrib, or rachis, smooth or rough? What color are the scales of the stalk? Do you think that these scales once wrapped the fern bud?

3. Does each frond of a clump have the same number of pinnæ on each side? Can you find fronds where the pinnæ near the tip are narrower than those below? Take a lower pinna and draw it carefully, showing its shape, its edges and its veins. Is there a point, or ear, at the base of every pinna? Is it a separate lobe or a mere point of the pinna?

4. Take one of the narrow pinnæ near the tip of the frond, and examine it beneath. Can you see some circular, roundish blisterlike dots? Are they dented at the center? How many of these dots on a pinna? Make a little sketch showing how they are arranged on the pinna and on the little earlike point. Look at the fruiting pinnæ of a fern during July, and describe how they look then.

5. Do all the fronds of a fern clump have these narrowed spore-bearing pinnæ? Do you know what those fronds are called that bear the fruit-dots?

6. Where do you find the Christmas fern growing? Do you ever find it in a sunny place? Why is it called the Christmas fern?

* * * * *

_FERN SONG_

_Dance to the beat of the rain, little Fern
And spread out your palms again,
And say, “Tho’ the sun
Hath my vesture spun,
He had labored, alas, in vain,
But for the shade
That the Cloud hath made,
And the gift of the Dew and the Rain.”
Then laugh and upturn
All your fronds, little Fern,
And rejoice in the beat of the rain!_
--JOHN B. TABB.

THE BRACKEN

_Teacher’s Story_

Photo by Verne Morton.]

It is well for the children to study the animals and plants which have a world-wide distribution. There is something comforting in finding a familiar plant in strange countries; and when I have found the bracken on the coast ranges of California, on the rugged sides of the Alps, and in many other far places, I have always experienced a thrill of delightful memories of the fence corners of the homestead farm. Since the bracken is so widespread, it is natural that it should find a place in literature and popular legend. As it clothes the mountains of Scotland, it is much sung of in Scottish poetry. Many superstitions cluster around it--its seed, if caught at midnight on a white napkin, is supposed to render the possessor invisible. Professor Clute, in Our Ferns in Their Haunts, gives a delightful chapter about the relation of the bracken to people.

For nature-study purposes, the bracken is valuable as a lesson on the intricate patterns of the fern leaf; it is in fact a lesson in pinnateness. The two lower branches are large and spreading and are in themselves often three times pinnate; the branches higher up are twice pinnate; while the main branch near the tip is once pinnate, and at the tip is merely lobed. The lesson, as illustrated in the diagram of the fern, should be well learned for future study, because this nomenclature is used in all the fern manuals. The fact that a pinnule is merely the last division of a frond, whether it be twice or thrice pinnate, should also be understood.

The bracken does not love complete shade and establishes itself in waste places, living contentedly in not too shaded locations; it is especially fond of woodsides, and fence corners on high and cold land. As Professor Clute says, “It is found both in woodland and in the open field; its favorite haunt is neither, but is that half-way ground where man leaves oft and nature begins, the copse or the thicket.” With us it usually grows about three feet high, but varies much in this respect. The great triangular fronds often measure two or three feet across, and are supposed to bear a likeness to an eagle with spread wings. Its rootstock is usually too deeply embedded in earth for the study of any except the most energetic; it is about the size of a lead pencil and is black and smooth; in its way it is a great traveler, sending up fronds fifteen or twenty feet from its starting place. It also sends off branching rootstocks.

_1. Fruiting pinnules of the maiden-hair fern, enlarged._
_2. Fruiting pinnule of the bracken, enlarged. In both these
species the spores are borne under the recurved edges of the
pinnules._
]

The fruiting pinnules look as if they were hemmed and the edges of the hems embroidered with brown wool; but the embroidery is simply the spore-cases pushing out from under the folded margin which protected them while developing.

Much on which to base necromancy has been found in the figure shown in the cross-section of the stem or stipe. The letter C, supposed to stand for Christ, thus made is a potent protection from witches. But this figure has also been compared to the devil’s hoof, an oak tree, or the initial of one’s sweetheart, and all these imaginings have played their part in the lives of the people of past ages. It was believed in England that burning the bracken from the fields brought rain; the roots in time of scarcity have been ground and mixed with flour to make bread. The young ferns, or croziers, are sometimes cooked and eaten like asparagus. The fronds have been used extensively for tanning leather and for packing fish and fruit, and when burned their ashes are used instead of soap.

In Europe, bracken grows so rankly that it is used for roof-thatching and for the bedding of cattle. The name “brake,” which is loosely used for all ferns, comes from the word “bracken;” some people think that brakes are different from ferns, whereas this is simply a name which has strayed from the bracken to other species. Its scientific name, _Pteris aquilina_, signifies eagle’s wing.

LESSON CLXXIV

THE BRACKEN

_Leading thought_--The bracken is a fern which has taken possession of the world. It is much branched and divided, and it covers the ground in masses where it grows. The edges of its pinnules are folded under to protect the spores.

_Method_--Bring to the schoolroom large and small specimens of the bracken, and after a study is made tell about the superstitions connected with this fern and as far as possible interest the pupils in its literature.

_Observations_--1. Do you find the bracken growing in the woods or open places? Do you find it in the cultivated fields? How high does it stand? Could you find the rootstock?

2. Take a bracken frond. What is its general shape? Does it remind you of an eagle with spread wings? Look at its very tip. Is it pinnate or merely lobed? Can you find a place farther down where the leaflets, or pinnules, are not joined at their bases? This is once pinnate. Look farther down and find a pinna that is lobed at the tip; at the base it has distinct pinnules. This is twice pinnate. Look at the lowest divisions of all. Can you find any part of this which is three times pinnate? Four times pinnate? Pinna means feather, pinnate therefore means feathered. If a thing is once pinnate, it means that it has divisions along each side similar to a feather; twice pinnate means that each feather has little feathers along each side; thrice pinnate means that the little feathers have similar feathers along each side, and so on.

3. Can you see if the edges of the pinnules are folded under? Lift up one of these edges and see if you can find what is growing beneath it. How do these folded margins look during August and September?

4. Cut the stem, or stipe, of a bracken across and see the figure in it. Does it look like the initial C? Or a hoof, or an oak tree, or another initial?

5. Discover, if you can, the different uses which people of other countries find for this fern.

HOW A FERN BUD UNFOLDS

_Teacher’s Story_

Of all “plant babies,” that of the fern is most cozily cuddled; one feels when looking at it, that not only are its eyes shut but its fists are tightly closed. But the first glance at one of these little woolly spirals gives us but small conception of its marvelous enfolding, all so systematic and perfect that it seems another evidence of the divine origin of mathematics. Every part of the frond is present in that bud, even to the fruiting organs; all the pinnæ and the pinnules are packed in the smallest compass--each division, even to the smallest pinnule, coiled in a spiral towards its base. These coiled fern buds are called crosiers; they are woolly, with scales instead of hairs, and are thus well blanketed. Some botanists object to the comparison of the woolly or fuzzy clothing of young plants with the blankets of human infants. It is true that the young plant is not kept at a higher temperature by this covering; but because of it, transpiration which is a cooling process is prevented, and thus the plant is kept warmer. When the fern commences to grow, it stretches up and seems to lean over backward in its effort to be bigger. First the main stem, or rachis, loosens its coil; but before this is completed, the pinnæ, which are coiled at right angles to the main stem, begin to unfold; a little later the pinnules, which are folded at right angles to the pinnæ, loosen and seem to stretch and yawn before taking a look at the world which they have just entered; it may be several days before all signs of the complex coiling disappear. The crosiers of the bracken are queer looking creatures, soon developing three claws which some people say look like the talons of an eagle; and so intricate is the action of their multitudinous spirals, that to watch them unfolding impresses one as in the presence of a miracle.

Photo by Verne Morton.]

LESSON CLXXV

HOW A FERN BUD UNFOLDS

_Leading thought_--All of the parts of the frond of a fern are tightly folded spirally within the bud, and every lobe of every leaflet is also folded in a spiral.

_Method_--The bracken crosier is a most illuminating object for this lesson, because it has so many divisions and is so large; it is also convenient, because it may be found in September. However, any fern bud will do. The lesson may be best given in May when the woodland ferns are starting. A fern root with its buds should be brought to the schoolroom, where the process of unfolding may be watched at leisure.

_Observations_--1. Take a very young bud. How does it look? Do you see any reason why ignorant people call these buds caterpillars? Can you see why they are popularly called “fiddle heads?” What is their true name? How many turns of the coil can you count? What is the covering of the crosier? Do you think this cover is a protection? How is the stem grooved to make the spiral compact?

2. Take a crosier a little further advanced. How are its pinnæ folded? How is each pinnule of each pinna folded? How is each lobe of a pinnule folded? Is each smaller part coiled toward each larger part?

3. Write in your note-book the story of the unfolding fern, and sketch its stages each day from the time it is cuddled down in a spiral until it is a fully expanded frond.

THE FRUITING OF THE FERN

_Teacher’s Story_

“_If we were required to know the position of the fruit-dots
or the character of the indusium, nothing could be easier than
to ascertain it; but if it is required that you be affected
by ferns, that they amount to anything, signify anything to
you, that they be another sacred scripture and revelation
to you, help to redeem your life, this end is not so easily
accomplished._”--THOREAU.

_The walking fern._]

The fern, like the butterfly, seems to have several this-world incarnations; and perhaps the most wonderful of these is the spore. Shake the dust out of the ripened fern and each particle, although too small for the naked eye to see, has within it the possibilities of developing a mass of graceful ferns. Each spore has an outside hard layer, and within this an atom of fern-substance; but it cannot be developed unless it falls into some warm, damp place favorable for its growth; it may have to wait many years before chance gives it this favorable condition, but it is strong and patient and retains its vital power for years. There are cases known where spores grew after twenty years of waiting. But what does this microscopic atom grow into? It develops into a tiny heart-shaped, leaflike structure which botanists call the prothallium; this has on its lower side little roots which reach down into the soil for nourishment; and on its upper surface are two kinds of pockets, one round and the other long. In the round pockets are developed bodies which may be compared to the pollen; and in the long pockets, bodies which may be compared to the ovules of flowering plants. In the case of ferns, water is necessary to float the pollen from the round pockets to the ovules in the long pockets. From a germ thus fertilized in one of the long pockets, a little green fern starts to grow, although it may be several years before it becomes a plant strong enough to send up fronds with spore-dots on them. To study the structure of the spore requires the highest powers of the microscope; and even the prothallium in most species is very small, varying from the size of a pin-head to that of a small pea, and it is therefore quite difficult to find. I found some once on a mossy log that bridged a stream, and I was never so triumphant over any other outdoor achievement. They may be found in damp places, in greenhouses, but the teacher will be very fortunate who is able to show her pupils this stage of the fern. The prothallium is a stage of the fern to be compared to the flower and seed combined in the higher plants; but this is difficult for young minds to comprehend. I like to tell the children that the fern, like a butterfly, has several stages: Beginning with the spore-bearing fern, we next have the spores, next the prothallium stage, and then the young fern. While in the other case we have first the egg, then the caterpillar, then the chrysalis, and then the butterfly. Looking at the ripe fruit-dots on the lower side of the fern leaf, we can easily see with a lens a mass of tiny globules; each one of these is a spore-case, or sporangium, (plural _sporangia_), and is fastened to the leaf by a stalk and has, almost encircling it, a jointed ring. (See figure on page 686).

_Prothallium, greatly enlarged, showing the two kinds of
pockets and the rootlets._
]

Photo by Verne Morton.]

1. _a_, pinna bearing fruit: _b_, a fruit-dot, enlarged,
showing spore-cases pushing out around the edges of the
indusium, _c_, spore-case, enlarged, showing how it discharges
the spores.

2. Prothallium, enlarged.

3. Young fern growing from the prothallium.
]

When the spores are ripe, this ring straightens out and ruptures the globule, and out fly the spores. By scraping a little of the brown fuzz from a fruiting pinna of the Christmas fern upon a glass slide and placing a cover glass upon it, we find it very easy to examine through the microscope, and we are able thus to find the spore-cases in all stages, and to see the spores distinctly. The spore-cases may also be seen with a hand lens, the spores seeming then to be mere dust.

The different ways the ferns blanket their spore-cases is a delightful study, and one which the pupils enjoy very much. All of our common ferns except the careless little polypody thus protect their spores. Whether this blanket be circular, or horseshoe-shaped, or oblong, or in the form of pocket or cup, depends upon the genus to which the fern belongs. The little protecting blanket-membrane is called the _indusium_, and while its shape distinguishes the genus, the position in which it grows determines the species. I shall never forget my surprise and delight when, as a young girl, I visited the Philadelphia Centennial Exposition, and there in the great conservatories saw for the first time the tree-ferns of the tropics. One of these was labelled _Dicksonia_, and mystified, I asked the privilege of examining the fronds for fruiting organs. When lo! the indusium proved to be a little cup, borne at the base of the tooth of the pinnule, exactly like that of our boulder fern, which is also a Dicksonia. I had a sudden feeling that I must have fern friends all over the world.

_1. Fruiting pinnule of the boulder fern, enlarged._ _2.
Fruiting pinnules of spleenwort, enlarged._
]

The children are always interested in the way the maidenhair folds over the tips of her scallops to protect her spore nursery; and while many of our ferns have their fertile fronds very similar in form to the sterile ones, yet there are many common ferns with fertile fronds that look so different from the others, that one would not think they were originally of the same pattern; but although their pinnules are changed into cups, or spore-pockets, of various shapes, if they be examined carefully they will be seen to have the same general structure and the same divisions however much contracted, as have the large sterile fronds. The Osmundas, which include the interrupted, the cinnamon and the flowering ferns, are especially good for this part of the lesson. The sensitive fern, so common in damp places in open fields, is also an excellent illustration of this method of fruiting. While studying the ferns, the teacher should lay stress upon the fact that they represent the earliest and simplest forms of plants, that they reached the zenith of their growth in the Carboniferous age, and that, to a large extent, our coal is composed of them. It is interesting to think that the exquisite and intricate leaf patterns of the ferns should belong to a primitive type. Often when I have watched the forming by the frost, of the exquisite fernlike pictures on the window-pane, I have wondered if, after all, the first expression of the Creator did not find form in the most exquisite grace and beauty; and if perchance the first fishes, so fierce and terrible, did not mark the introduction of Satan.

LESSON CLXXVI

THE FRUITING OF THE FERN

_Leading thought_--Ferns do not have flowers, but they produce spores. Spores are not seeds; but they grow into something which may be compared to a true seed, and this in turn develops into young ferns. Each genus of ferns has its own peculiar way of protecting its spores; and if we learn these different ways, we can recognize ferns without effort.

_Method_--July is the best time for this lesson, which is well adapted for summer schools or camping trips. However, if it is desired to use it as a school lesson, it should be begun in June, when the fruiting organs are green, and it may be finished in September after the spores are discharged. Begin with the Christmas fern, which ripens in June, and make the fruiting of this species a basis for comparison. Follow this with other wood ferns which bear fruit-dots on the back of the fronds. Then study the ferns which live in more open places, and which have fronds changed in form to bear the spores--like the sensitive, the ostrich, the royal and the flowering ferns. A study of the interrupted fern is a desirable preparation for the further study of those which have special fruiting fronds; the interrupted fern has, at about the middle of its frond, three pinnæ on each side, fitted for spore-bearing, the pinnules being changed into globular cups filled with spore-cases.

While not absolutely necessary, it is highly desirable that each member of the class should look at a fruit-dot of some fern through a three-quarters objective of a compound microscope, and then examine the spore-cases and the spores through a one-sixth objective. It must be remembered that this lesson is for advanced grades, and is a preparation for systematic scientific work. If a microscope is not available, the work may be done with a hand lens aided by pictures.

_Diagram of the interrupted fern, showing the three pairs of
fruiting pinnæ, and a part of one of these enlarged. This fern
often has fronds four or five feet high._
]

_Observations_--1. Take a fern that is in fruit; lay it on a sheet of white paper and leave it thus for a day or two, where it will not be disturbed and where there is no draught; then take it up carefully; the form of the fern will be outlined in dust. What is this dust?

2. What conditions must the spores have in order to grow? What do they grow into? (See First Studies of Plant Life by Atkinson, p. 207).

3. Look at a ripe fruit-dot on the back of a fern leaf and see where the spores come from. Can you see with a lens many little, brown globules? Can you see that some of them are torn open? These are the spore-cases, called _sporangia_, each globule being packed with spores. Can you see how the sporangia are fastened to the leaf by little stems?

4. Almost all our common wood ferns have the spore-cases protected by a thin membrane, the spore-blanket, when very young; this little membrane is called the _indusium_, and it is of different shape in those ferns which do not have the same sirname, or generic name. Study as many kinds of wood ferns as you can find. If the blanket, or indusium, is circular with a dent at the center where it is fastened to the leaf, and the spore-cases push out around the margin, it is a _Christmas fern_; if horseshoe-shaped, it is one of the _wood ferns_; if oblong, in rows on each side of the midrib, it is a _chain fern_; but if oblong and at an angle to the midrib, it is a _spleenwort_; if it is pocket-shaped and opening at one side, it is a _bladder fern_; if it is cup-shaped, it is a _boulder fern_; if it breaks open and lays back in star shape, it is a _woodsia_; if the edge of the fern leaf is folded over all along its margin to protect the spore-cases, it is a _bracken_; if the tips of the scallops of the leaf be delicately folded over to make a spore blanket, it is the _maidenhair_.

5. If you know of swampy land where there are many tall brakes, look for a kind that has some of its pinnæ withered and brown. Examine these withered pinnæ, and you will see that they are not withered at all but are changed into little cups to hold spore-cases. This is the _interrupted fern_. The _flowering fern_ has the pinnæ at its tip changed into cups for spore-cases. The _cinnamon fern_, which grows in swampy places, has whole fronds which are cinnamon-colored and look withered, but which bear the spores. The ostrich fern, which has fronds which look like magnificent ostrich feathers, has stiff, little stalks of fruiting fronds very unlike the magnificent sterile fronds. The _sensitive fern_, which grows in damp meadows and along roadsides, also has contracted fruiting fronds. If you find any of these, compare carefully the fruiting with the sterile fronds, and note in each case the resemblance in branching and in pinnules and also the shape of the openings through which the spores are sifted out.

6. Gather and press specimens of as many ferns in the fruiting stage as you can find, taking both sterile and fruiting fronds in those species which have this specialization.

7. Read in the geologies about the ferns which helped to make our coal beds.

_Supplementary reading._--The Story of a Fern; First Studies of Plant Life, Atkinson; The Petrified Fern, M. L. B. Branch.

Photo by Verne Morton.]

* * * * *

“_Nature made ferns for pure leaves to see what she could do
in that line._”--THOREAU

THE FIELD HORSETAIL

_Teacher’s Story_

_1, Fertile plant of the field horsetail_; _2, spore_; _3,
disk discharging spores_; _4, disk with spore-sacs_.
]

These queer, pale plants grow in sandy or gravelly soil, and since they appear so early in the spring they are objects of curiosity to children. The stalk is pale and uncanny looking; the pinkish stem, all the same size from bottom to top, is ornamented at intervals with upward-pointing, slender, black, sharp-pointed scales, which unite at the bottom and encircle the stalk in a slightly bulging ring, a ring which shows a ridge for every scale, extending down the stem. These black scales are really leaves springing from a joint in the stem, but they forgot long ago how to do a leaf’s work of getting food from the air. The “blossom” which is not a real blossom in the eye of the botanist, is made up of rows of tiny discs which are set like miniature toadstools around the central stalk. Before it is ripe, there extends back from the edge of each disc a row of little sacs stuffed so full of green spores that they look united like a row of tiny green ridges. The discs at the top of the fertile spike discharge their spores first, as can be seen by shaking the plant over white paper, the falling spores looking like pale green powder. The burst and empty sacs are whitish, and hang around the discs in torn scallops, after the spores are shed. The spores, when seen under the microscope, are wonderful objects, each a little green ball with four spiral bands wound about it. These spirals uncoil and throw the spore, giving it a movement as of something alive. The motor power in these living springs is the absorbing of moisture.

The beginning of the sterile shoot can be seen like a green bit of the blossom spike of the plantain; but later, after the fertile stalks have died down, these cover the ground with their strange fringes.

The person who first called these sterile plants “horsetails” had an overworked imagination, or none at all; for the only quality the two have in common is brushiness. A horse which had the hair of its tail set in whorls with the same precision as this plant has its branches would be one of the world’s wonders. The _Equicetum_ is one of the plants which give evidence of nature’s resourcefulness; its remote ancestors probably had a whorl of leaves at each joint or node of the main stem and branches; but the plant now having so many green branches, does not really need the leaves, and thus they have been reduced to mere points, and look like nothing but “trimming,” they are so purely ornamental. Each little cup or socket, of the joint or node, in branch or stem, has a row of points around its margin, and these points are terminals of the angles in the branch. If a branch is triangular in cross section, it will have three points at its socket, if quadrangular it will have four points, and the main stem may have six or a dozen, or even more points. The main stem and branches are made up entirely of these segments, each set at its lower end in the socket of the segment behind or below it. These green branches, rich in chlorophyl, manufacture for the plant all the food that it needs. Late in the season this food is stored in the rootstocks, so that early next spring the fertile plants, nourished by this stored material, are able to push forth before most other plants, and thus develop their spores early in the season. There is a prothallium stage as in the ferns.

Above where the whorl of stems comes from the main branch, may be seen a row of upward-standing points which are the remnants of leaves; each branch as it leaves the stem is set in a little dark cup with a toothed rim. There is a nice gradation from the stout lower part of the stem to the tip, which is as delicate as one of the side branches.

The rootstock dies out behind the plant and pushes on ahead like the rootstock of ferns. The true roots may be seen attached on the under side. The food made in the summer is stored in little tubers, which may be seen in the rootstocks.

LESSON CLXXVII

THE FIELD HORSETAIL

_The Fertile Plant_

_Leading thought_--The horsetail is a plant that develops spores instead of seeds, and has green stems instead of leaves.

_Method_--In April and May, when the children are looking for flowers, they will find some of these weird looking plants. These should be brought to the schoolroom and the observation lesson given there.

_Observations_--1. Where are these plants found? On what kind of soil?

2. In what respect does this plant differ from other plants in appearance? Can you find any green part to it?

3. What color is the stem? Is it the same size its whole length? Is it smooth or rough?

4. Do you see any leaves on the stems? Do you see the black-pointed scales? In which direction do these scales point? Are they united at the bottom? What sort of a ring do they make around the stem? Split a stem lengthwise and see if there are joints, or nodes, where the ring joins the stalk.

5. How does the “blossom” look? What color are the little discs that make up the blossom? How are the discs set?

6. Take one of the plants which has the discs surrounded by green ridges. Shake it over a white paper. What comes from it? Where does it come from? Which discs on the stalk shed the green spores first?

_The Sterile Plants_

_Leading thought_--The horsetail or _Equicetum_ is nourished by very different looking stems than those which bore the spores. It lacks leaves, but its branches are green and do the work of making food for the plant.

_Method_--The sterile plants of the horsetail do not appear for several weeks after the fertile ones; they are much more numerous, and do not resemble the fertile plants in form or color. These sterile plants may be used for a lesson in September or October. Some of these plants with their roots may be brought into the schoolroom for study.

_Observations_--1. Has this plant any leaves? How does it make and digest its food without leaves? What part of it is green? Wherever there is green in a plant, there is the chlorophyl-factory for making food. In the horsetail, then, what part of the plant does the work of leaves?

2. Take off one little branch and study with the lens. How does it look? Pull it apart. Where does it break easily? How many joints, or nodes, are there in the branch?

3. Study the socket from which one of the segments was pulled off. What do you see around its edge? How many of these points? Look at the branch in cross section. How many angles has it? What relation do the points bear to the angles? Do you think these points are all there are left of true leaves?

4. How do the little green branches come off the main stem? How many in a place? How many whorls of branches on the main stem?

5. Study the bases of the branches. What do you see? Look directly above where the whorl of branches comes off the main stem. What do you see? Cut the main stem in cross-section just below this place, and see if there are as many little points as there are angles, or ridges, in the stem. Do you suppose these little points are the remnants of leaves on the main stem?

6. What kind of root has the horsetail? Do you think this long running root is the true root or an underground stem? Where are the true roots? Do you think the rootstock dies off at the oldest end each year, like the fern? Can you find the little tubers in the rootstock, which contain nourishment for next year’s spore-bearing stalks?

THE HAIR-CAP MOSS, OR PIGEON WHEAT

_Teacher’s Story_

Photo by Verne Morton.

_The hair-cap moss._]

The mosses are a special delight to children because they are green and beautiful before other plants have gained their greenness in the spring and after they have lost it in the fall; to the discerning eye, a mossy bank or a mossy log is a thing of beauty always. When we were children we regarded moss as a forest for fairy folk, each moss stem being a tree, and we naturally concluded that fairy forests were evergreen. We also had other diversions with pigeon wheat, for we took the fruiting stem, pulled the cap off the spore-capsule, tucked the other end of the red stem into the middle of the capsule, making a beautiful coral ring with an emerald “set.” To be sure these rings were rather too delicate to last long, but there were plenty more to be had for nothing; so we made these rings into long chains which we wore as necklaces for brief and happy moments, their evanescence being one of their charms.

Pigeon wheat is a rather large moss which grows on dry knolls, usually near the margins of damp woodlands in just those places where wintergreens love to grow. In fall or winter it forms a greenish brown mass of bristling stems; in the early summer the stems are tipped with the vivid green of the new growth. The bristling appearance comes from the long sharp leaves set thickly upon the ruddy brown stems; each leaf is pretty to look at with a lens, which reveals it as thick though narrow, grooved along the middle, the edges usually armed with sharp teeth and the base clasping the stem. These leaves, although so small, are wonderfully made; during the hot, dry weather they shut up lengthwise and twist into the merest threads, in order to keep their soft, green surfaces from losing their moisture by exposure to the air; more than this, they lift themselves and huddle close to the stem, and are thus as snug and safe as may be from the effect of drought; but as soon as the rains come, they straighten back at right angles to the stem, and curve their tips downward in a joyful expanding. Bring in some of this moss and let it dry, and then drop it into a glass of water and watch this miracle of leaf movement! And yet it is no miracle but a mechanism quite automatic--and therefore--like other miracles, when once they are understood.

1. fruit-bearing moss stem before fertilization; 1_a_, the
same stem after fruit is developed; _a_, where the ovule was
before fertilization; _b_, fruit stem; _c_, spore-capsule with
cap or veil upon it. 2, stem showing the starlike cups; _d_,
the cup in which was developed the pollen which fertilized
the ovule at _a_, this year; _e_, last year’s cup; _f_, the
cup of year before last; only the leaves from _e_ to _d_ are
alive. 3, spore capsule with the cap removed, showing the lid.
5, the cap or veil removed. 4, spore capsule with lid off and
shaking out the spores. 6, starlike cup in which the pollen is
developed. 7, leaf of moss; 8, the top of the spore capsule
showing the teeth around the edge between which the spores
sift out. 9, a part of a necklace chain made of the spore
capsules and their stems.
]

In early June the mossy knoll shows us the origin of the name pigeon grass or pigeon wheat, for it is then covered with a forest of shining, ruddy, stiff, little stems, each stem bearing on its tip a woolly object about the size of a grain of wheat. But it is safe to say that the pigeons and other birds enjoy our own kind of wheat better than this, which is attributed to them.

A study of one of these wheat grains reveals it as covered with a yellowish, mohair cap, ending in a golden brown peak at its tip, as if it were the original pattern of the toboggan cap; it closes loosely and downily around the stem below. This grain is the spore-capsule of the moss; the hairy cap pulls off easily when seized by its tip. This cap is present at the very beginning, even before the stem lengthens, to protect the delicate tissues of the growing spore-case; it is only through a lens that we can see it in all its silky softness. The capsule revealed by the removal of the cap is a beautiful green object, usually four-sided, set upon an elegant little pedestal where it joins the coral stem, and with a lid on its top like a sugar-bowl cover, with a point instead of a knob at its center. When the spores are ripe, this lid falls off, and then if we have a lens we may see another instance of moss mechanism. Looking at the uncovered end of the capsule, we see a row of tiny teeth around the margin, which seem to hold down an inner cover with a little raised rim. The botanists have counted these teeth and find there are 64. The teeth themselves are not important, but the openings between them are, since only through these openings can the spores escape. In fact, the capsule is a pepper-box with a grating around its upper edge instead of holes in its cover; and when it is fully ripe, instead of standing right side up, it tips over so as to shake out its spores more easily. These teeth are like the moss leaves; they swell with moisture, and thus in rainy weather they, with the inner cover, swell so that not a single spore can be shaken out. If spores should come out during the rain, they would fall among the parent plants where there is no room for growth. But when they emerge in dry weather, the wind scatters them far and wide where there is room for development.

When seen with the naked eye, the spores seem to be simply fine dust, but each dust grain is able to produce moss plants. However, the spore does not grow up into a plant like a seed, it grows into fine, green, branching threads which push along the surface of damp soil; on these threads little buds appear, each of which grows up into a moss stem.

The spore-capsule is hardly the fruit of the moss plant. If we examine the moss, we find that some stems end in yellowish cups which look almost like blossoms; on closer examination, we find that there are several of these cups, one below the other, with the stem extending up through the middle. The upper cup matured this year, the one below it last year, and so on. These cups are star-pointed, and inside, at the bottom, is a starlike cluster of leaves. Among the leaves of this star-rosette are borne the moss anthers called _antheridii_, too small for us to see without a high power microscope. The pollen from these anthers is blown over to other plants, some of which produce ovules at their very tips, although the ovule has no leaf-rosette to show where it is. This ovule, after receiving the pollen, grows into the spore-capsule supported on its coral stem. These--stem, capsule and all--grow up out of the mother plant, the red stem is enlarged at its base, and fits into the moss stem like a flagstaff in the socket. After the star-shaped cup has shed its pollen, the stem grows up from its center for an inch or so in height and bears new leaves, and next year will bear another starry cup.

The brown leaves on the lower part of the moss stem are dead, and only the green leaves on the upper part are living.

And this is the story of the moss cycle:

1. A plant with an ovule at its tip; another plant with a star-cup holding the moss pollen which is sifted by wind over to the waiting egg.

2. The egg or ovule as soon as fertilized develops into a spore-capsule, and is lifted up into the world on a beautiful shining stem and is protected by a silky cap.

3. The cap comes off; the lid of the spore-case falls off, the spores are shaken out and scattered by the wind.

4. Those spores that find fitting places grow into a net of green threads.

5. These green threads send up moss stems which repeat the story.

LESSON CLXXVIII

THE HAIR-CAP MOSS

_Leading thought_--The mosses, like the butterfly and the fern, have several stages in their development. The butterfly stages are the egg, the caterpillar, the chrysalis, the butterfly. The moss stages are the egg (or ovule), the spores, the branching green threads, the moss plants with their green foliage. In June we can easily find all these stages, except perhaps the branching thread stage.

_Method_--The children should bring to the schoolroom a basin of moss in its fruiting stage; or still better, go with them to a knoll covered with moss. Incidentally tell them that this moss, when dried, is used by the Laplanders for stuffing their pillows, and that the bears use it for their beds. Once, a long time ago, people believed that a plant, by the shape of its leaf or flower, indicated its nature as a medicine, and as this moss looked like hair, the water in which it was steeped was used as a hair tonic.

_Observation_--1. Take a moss stem with a grain of pigeon wheat at the end. Examine the lower part of the stalk. How are the leaves arranged on it? Examine one of the little leaves through a lens and describe its shape, its edges, and the way it joins the stem. Are the lower leaves the same color as the upper ones? Why?

2. Describe the pretty shining stem of the fruit, which is called the pedicel. Is it the same color for its entire length? Can you pull it easily from the main plant? Describe how its base is embedded in the tip of the plant.

3. Note the silken cap on a grain of the pigeon wheat. This is called the veil. Is it all the same color? Is it grown fast to the plant at its lower margin? Take it by the tip, and pull it off. Is this done easily? Describe what it covers. This elegant little green vase is called a spore-capsule. How many sides has it? Describe its base which stands upon the stem. Describe the little lid. Pull off the lid; is there another lid below it? Can you see the tiny teeth around the edge which hold this lid in place? Ask your teacher, or read in the books, the purpose of this.

4. Do all the spore vases stand straight up, or do some bend over?

5. Do you think the silken cap falls off of itself after a while? Can you find any capsules where the cap or veil and the lid have fallen off? See if you can shake any dust out of such a spore vase. What do you think this dust is? Ask your teacher, or read in the books, about moss spores and what happens if they find a damp place in which to grow.