that the term is coined to cover, and leave the reader to formulate a
short concise statement of its meaning.
Within the last year a new botanical guide book for teachers has
been published, of considerable originality and merit, in which
the subject-matter is thrown into four groups, and one of these is
Ecology. Another text-book for secondary schools is now before us in
which ecology is the heading of one of the three parts into which the
treatise is divided. The large output of the educational press at the
present time along the line in hand suggests that the magazine press
should sound the depths of the new branch of science that is pushing
its way to the front, or being so pushed by its adherents, and echo the
merits of it along the line.
Botany in its stages of growth is interesting historically. It
fascinated for a time one of the greatest minds in the modern school,
and as a result we have the rich and fruitful history of the science
as seen through eyes as great as Julius Sachs's, the master of botany
during the last half century. From this work it can be gathered that
early in the centuries since the Christian era botany was little more
than herborizing--the collecting of specimens, and learning their gross
parts, as size of stem and leaf and blossom.
This branch of botany has been cultivated to the present day, and the
result is the systematist, with all the refinements of species making
and readjustment of genera and orders with the nicety of detail in
specific descriptions that only a systematist can fully appreciate.
Later on the study of function was begun, and along with it that of
structure; for anatomy and physiology, by whatever terms they may be
known, advance hand in hand, because inseparable. One worker may look
more to the activities than another who toils with the structural
relations and finds these problems enough for a lifetime.
This botany of the dissecting table in contrast with that of the
collector and his dried specimens grew apace, taking new leases of
life at the uprising of new hypotheses, and long advances with the
improvement of implements for work. It was natural that the cell and
all that is made from it should invite the inspector to a field of
intense interest, somewhat at the expense of the functions of the
parts. In short, the field was open, the race was on, and it was a
matter of self-restraint that a man did not enter and strive long and
well for some anatomical prize. This branch of botany is still alive,
and never more so than to-day, when cytology offers many attractive
problems for the cytologist. What with his microtome that cuts his
imbedded tissue into slices so thin that twenty-five hundred or more
are needed to measure an inch in thickness, with his fixing solutions
that kill instantly and hold each particle as if frozen in a cake of
ice, and his stains and double stains that pick out the specks as the
magnet draws iron filing from a bin of bran--with all these and a
hundred more aids to the refinement of the art there is no wonder that
the cell becomes a center of attraction, beyond the periphery of which
the student can scarcely live. In our closing days of the century it
may be known whether the blephroblasts arise antipodally, and whether
they are a variation of the centrosomes or should be classed by
themselves!
One of the general views of phytoecology is that the forms of plants
are modified to adapt them to the conditions under which they exist.
Thus the size of a plant is greatly modified by the environment.
Two grains of corn indistinguishable in themselves and borne by the
same cob may be so situated that one grows into a stately stalk with
the ear higher than a horse's head, while the other is a dwarf and
unproductive. Below ground the conditions are many, and all subject
to infinite variation. Thus, the soil may be deep or shallow, the
particles small or large, the moisture abundant or scant, and the food
elements close at hand or far to seek--all of which will have a marked
influence upon the root system, its size, and form.
Coming to the aërial portion, there are all the factors of weather and
climate to work singly or in union to affect the above-ground structure
of the plant. Temperature varies through wide ranges of heat and
cold, scorching and freezing; while humidity or aridity, sunshine or
cloudiness, prevailing winds or sudden tornadoes all have an influence
in shaping the structure, developing the part, and fashioning the
details of form of the aërial portions. Phytoecology deals with all
these, and includes the consideration of that struggle for life that
plants are constantly waging, for environment determines that the forms
best suited to a given set of conditions will survive. This struggle
has been going on since the vegetable life of the earth began, and as
a result certain prevailing conditions have brought about groups of
plants found as a rule only where these conditions prevail. As water
is a leading factor in plant growth, a classification is made upon
this basis into the plants of the arid regions called xerophytes. The
opposite to desert vegetation is that of the fresh ponds and lakes,
called hydrophytes. A third group, the halophytes, includes the
vegetation of sea or land where there is an excess of various saline
substances, the common salt being the leading one. The last group is
the mesophytes, which include plants growing in conditions without the
extremes accorded to the other three groups.
This somewhat general classification of the conditions of the
environment lends much of interest to that form of field botany now
under consideration. As the grouping is made chiefly upon the aqueous
conditions, it is fair to assume that plants are especially modified
to accommodate themselves to this compound. Plants, for example,
unless they are aquatics, need to use large quantities of water to
carry on the vital functions. Thus the salts from the soil need to
rise dissolved in the crude sap to the leaves, and in order that a
sufficient current be kept up there is transpiration going on from
all thin or soft exposed parts. The leaves are the chief organs where
aqueous vapor is being given off, sometimes to the extent of tons of
water upon an acre of area in a single day. This evaporation being
largely surface action, it is possible for the plant to check this by
reducing the surface, and the leaf is coiled or folded. Other plants
have through the ages become adapted to the destructive actions of
drought and a dry, hot atmosphere, and have only needle-shaped leaves
or even no true ones at all, as many of the cacti in the desert lands
of the Western plains.
Again, the surface of the plant may become covered with a felt of fine
hairs to prevent rapid evaporation, while other plants with ordinary
foliage have the acquired power of moving the leaves so that they will
expose their surfaces broadside to the sun, or contrariwise the edges
only, as heat and light intensity determine.
Phytoecology deals with all those adaptations of structure, and from
which permit the plants to take advantage of the habits and wants of
animals. If we are studying the vegetation of a bog, and note the
adaptation of the hydrophytic plants, the chances are that attention
will soon be called to colorations and structures that indicate a more
complete and far-reaching adjustment than simply to the conditions of
the wet, spongy bog. A plant may be met with having the leaves in the
form of flasks or pitchers, and more or less filled with water. These
strange leaves are conspicuously purplish, and this adds to their
attractiveness. The upper portion may be variegated, resembling a
flower and for the same purpose--namely, to attract insects that find
within the pitchers a food which is sought at the risk of life. Many
of the entrapped creatures never escape, and yield up their life for
the support of that of the captor. Again, the mossy bog may glisten
in the sun, and thousands of sundew plants with their pink leaves are
growing upon the surface. Each leaf is covered with adhesive stalked
glands, and insects lured to and caught by them are devoured by this
insectivorous vegetation.
In the pools in the same lowland there may be an abundance of the
bladderwort, a floating plant with flowers upon long stalks that raise
them into the air and sunshine. With the leaves reduced to a mere
framework that bears innumerable bladders, water animals of small
size are captured in vast numbers and provide a large part of the
nourishment required by the highly specialized hydrophyte.
These are but everyday instances of adaptation between plants and
animals for the purpose of nutrition, the adjustment of form being
more particularly upon the vegetative side. Zoölogists may be able to
show, however, that certain species of animals are adapted to and quite
dependent upon the carnivorous plants.
An ecological problem has been worked out along the above line to a
larger extent than generally supposed. If we should take the case of
ants only in their relation to structural adaptations for them in
plants, it would be seen that fully three thousand species of the
latter make use of ants for purposes of protection. The large fighting
ants of the tropics, when provided with nectar, food, and shelter,
will inhabit plants to the partial exclusion of destructive insects
and larger foraging animals. Interesting as all this is, it is not the
time and place to go into the details of how the ant-fostering plants
have their nectar glands upon stems or leaf, rich soft hairs in tufts
for food, and homes provided in hollows and chambers. There is still a
more intimate association of termites with some of the toadstool-like
plants, where the ants foster the fungi and seem to understand some of
the essentials of veritable gardening in miniature form.
The most familiar branch of phytoecology, as it concerns adaptations
for insect visitations, is that which relates to the production of
seed. Floral structures, so wonderfully varied in form and color and
withal attractive to every lover of the beautiful, are familiar to all,
and it only needs to be said in passing that these infinite forms are
for the same end--namely, the union of the seed germs, if they may be
so styled, of different and often widely separated blossoms.
Sweetness and beauty are not the invariable rule with insect-visited
blossoms, for in the long ages that have elapsed during which these
adaptations have come about some plants have established an unwritten
agreement between beetles and bugs with unsavory tastes. Thus there are
the "carrion flowers," so called because of their fetid odor, designed
for the sense organs of carrion insects. The "stink-horn" fungi have
their offensive spores distributed by a similar set of carrion carriers.
Water and wind claim a share of the species, but here adaptation to
the method of fertilization is as fully realized as when insects
participate, and the uselessness of showy petals and fantastic forms is
emphasized by their absence.
Coming now to the fruits of plants, it is again seen that plants have
adapted their offspring, the seed, to the surrounding conditions,
not forgetting the wind, the waves, and the tastes and the exterior
of passing animals. The breezes carry up and hurl along the light
wing-possessed seeds, and the river and ocean bear these and many
others onward to a distant land, while by grappling hooks many kinds
cling to the hair of animals, or, provided with a pleasing pulp, are
carried willingly by birds and other creatures. In short, the devices
for seed dispersion are multitudinous, and they provide a large chapter
in that branch of botany now styled phytoecology.
How different is the old field botany from the new! Then there was the
collector of plants and classifier of his finds, and an arranger of all
he could get by exchange or otherwise. His success was measured by the
size of his herbarium and his stock in trade as so many duplicates
all taken in bloom, but the time of year, locality, and the various
conditions of growth were all unknown.
His implements for work were, first, a can or basket, a plant press,
and a manual; and, secondly, a lot of paper, a paste pot, and some way
of holding the mounts in packets or pigeonholes.
The eyes grew keen as the hunter scoured the forest and field for some
kind of plant he had not already possessed. There was a keen relish in
discoveries, and it heightened into ecstasy when the specimen needed
to be sent away for a name and was returned with his own Latinized and
appended to that of the genus.
This was all well and good so far as it went, but looked at from the
present vantage ground there was not so much in it. However, his was an
essential step to other things, as much so as that of the census taker.
We need to know the species of plants our fair land possesses, and have
them described and named. But when the nine hundred and ninety-nine
are known, it is a waste of time to be continually hunting for the
thousandth. Look for it, but let it be secondary to that of an actual
study of the great majority already known. The older botany was a study
of the dried plants in all those details that are laid down in the
manuals. It lacked something of the true vitality that is inherent in a
biological science, for often the life had gone out before the subject
came up for study. To the phytoecologist it was somewhat as the shell
without the meat, or the bird's nest of a previous year.
Since those days of our forefathers there has come the minute anatomy
of plants, followed closely by physiology; and now with the working
knowledge of these two modern branches of botany the student has
again taken to the field. He is making the wood-lot his laboratory,
and the garden, so to say, his lecture room. He has a fair knowledge
of systematic botany, but finds himself rearranging the families
and genera to fit the facts determined by his ecological study. If
two species of the same genus are widely separated in habitat, he
is determining the factors that led to the separation. Why did one
smart weed become a climber, another an upright herb, and a third a
prostrate creeper, are questions that may not have entered the mind of
the plant collector; but now the phytoecologist finds much interest in
considering questions of this type. What are the differences between
a species inhabiting the water and another of the same genus upon dry
land, or what has led one group of the morning-glory family to become
parasites and exist as the dodders upon other living plants?
The older botanist held his subject under the best mental illumination
of his time, but his physical light, that of a pine knot or a tallow
dip, also contrasts strongly with that of the present gas jet and
electric arc.
The wonder should be that he saw so well, and all who follow him can
not but feel grateful for the path he blazed through the dense forests
of ignorance and the bridges he made over the streams of doubt in
specific distinctions. It was a noble work, but it is nearly past in
the older parts of our country; and while some of that school should
linger to readjust their genera, make new combinations of species,
and attempt to satisfy the claims of priority, the rank and file will
largely leave systematic botany and the herborizing it embraces, and
betake themselves to the open fields of phytoecology. It may be along
the line of structural adaptations when we will have morphological
phytoecology, or the adjustment of function to the environment when
there will be physiological phytoecology. These two branches when
combined to elucidate problems of relationship between the plant and
its surroundings as involved in accommodation in its comprehensive
sense there will be phytoecology with climate, geology, geography, or
fossils as the leading feature, as the case may be.
In the older botany the plant alone in itself was the subject of study.
The newer botany takes the plant in its surroundings and all that its
relationships to other plants may suggest as the subject for analysis.
In the one case the plant was all and its place of growth accidental,
a dried specimen from any unknown habitat was enough; but now the
environment and the numerous lines of relationship that reach out from
the living plant _in situ_ are the major subjects for study. The former
was field botany because the field contained the plant, the latter is
field botany in that the plant embraces in its study all else in the
field in which it lives. The one had as its leading question, What is
your name and where do you belong in my herbarium? while the other
raises an endless list of queries, of which How came you here and when?
Why these curious glands and this strange movement or mimicry? are but
average samples. Every spot of color, bend of leaf, and shape of fruit
raises a question.
The collector of fifty years ago pulled up or cut off a portion of
his plant for a specimen, and rarely measured, weighed, and counted
anything about it. The phytoecologist to-day watches his subject as
it grows, and if removed it is for the purpose of testing its vital
functions under varying circumstances of moisture, heat, or sunlight,
and exact recording instruments are a part of the equipment for the
investigation.
The underlying thought in the seashore school and the tropical
laboratory in botany is this of getting nearer to the haunts of the
living plant. Forestry schools that have for their class room the
wooded mountains and the botanical gardens with their living herbaria
are welcome steps toward the same end of phytoecology.
In view of the above facts, and many more that might be mentioned did
space permit, the writer has felt that the present incomplete and
faulty presentation of the subject of the newer botany should be placed
before the great reading public through the medium of a journal that
has as its watchword Progress in Education.
DO ANIMALS REASON?
BY THE REV. EGERTON R. YOUNG.
This interesting subject has been ably handled from the negative side
by Edward Thorndike, Ph. D., in the August number of the Popular
Science Monthly. Dr. Thorndike, with all his skill in treating this
very interesting subject, seems to have forgotten one very important
point. His expectation has not only been higher than any fair claim of
an animal's reasoning power, but he has overlooked the fact that there
are different ways of reasoning. Men of different races and those of
little intelligence can be placed in new environments and be asked to
perform things which, while utterly impossible to them, are simple and
crude to those of higher intelligence and who have all their days been
accustomed to high mental exercise. If such difference exists between
the highest and most intelligent of the human race and the degraded
and uncultured, vastly greater is the gulf that separates the lowest
stratum of humanity from the most intelligent of the brute creation.
The fair way to test the intelligence of the so-called lower orders
of men is to go to their native lands and study them in their own
environments and in possession of the equipments of life to which they
have been accustomed. The same is true of the brute creation. Only
the highest results can be expected from congenial environments. To
pass final judgment upon the animal kingdom, having for data only the
results of the doctor's experiments, seems to us manifestly unfair.
He takes a few cats and dogs and submits them to environments which
are altogether foreign to them, and then expects feats of mind from
them which would be far greater than the mastering of the reason why
two and two make four is to the stupidest child of man. As the doctor
has been permitted to tell the results of his experiments, may I claim
a similar privilege? While I did not use dogs merely to test their
intelligence--my business demanding of myself and them the fullest use
of all our energies and all the intelligence, be it more or less, that
was possessed by man or beast--I had the privilege of seeing in my dogs
actions that were, at least to me, convincing that they possessed the
rudiments of reasoning powers, and, in the more intelligent, that which
will be utterly inexplicable if it is not the product of reasoning
faculties.
For a number of years I was a resident missionary in the Hudson Bay
Territories, where, in the prosecution of my work, I kept a large
number of dogs of various breeds. With these dogs I traveled several
thousands of miles every winter over an area larger than the State of
New York. In summer I used them to plow my garden and fields. They
dragged home our fish from the distant fisheries, and the wood from the
forests for our numerous fires. They cuddled around me on the edges of
my heavy fur robes in wintry camps, where we often slept out in a hole
dug in the snow, the temperature ranging from 30° to 60° below zero.
When blizzard storms raged so terribly that even the most experienced
Indian guides were bewildered, and knew not north from south or east
from west, our sole reliance was on our dogs, and with an intelligence
and an endurance that ever won our admiration they succeeded in
bringing us to our desired destination.
It is conceded at the outset that these dogs of whom I write were the
result of careful selection. There are dogs and dogs, as there are
men and men. They were not picked up in the street at random. I would
no more keep in my personal service a mere average mongrel dog than I
would the second time hire for one of my long trips a sulky Indian. As
there are some people, good in many ways, who can not master a foreign
tongue, so there are many dogs that never rise above the one gift of
animal instinct. With such I too have struggled, and long and patiently
labored, and if of them only I were writing I would unhesitatingly say
that of them I never saw any act which ever seemed to show reasoning
powers. But there are other dogs than these, and of them I here would
write and give my reason why I firmly believe that in a marked degree
some of them possessed the powers of reasoning.
Two of my favorite dogs I called Jack and Cuffy. Jack was a great black
St. Bernard, weighing nearly two hundred pounds. Cuffy was a pure
Newfoundland, with very black curly hair. These two dogs were the gift
of the late Senator Sanford. With other fine dogs of the same breeds,
they soon supplanted the Eskimo and mongrels that had been previously
used for years about the place.
[Illustration: JACK AND HIS MASTER.]