The true northerner. [volume] (Paw Paw, Mich.) 1855-1920, 1903-04-17

coal, anu ITO uOuDt cOntTlDuteu thcii
share of organic material Of leaves and
bark and spores and wood, to form vast
beds OF fuel that, as we know, make
possible the wealth and convenience Of
the present
But the devonian has something bet
ter than club MOSES and ferns 10 show
us. even IL these did assume the size
OF trees. Bigness is not always syno-
nym for excellence From rocks OF
different parts OF the northern hem
isphere rocks belonging to the middle
deyonian, we have fossil coniferous
wood, specimens representing the mod
ern cone bearers-larches, spruces, yews
and pines. All the trees referred TO,
the spore bearing trees, seem 10 have
been confined to marshes and the damp
shores Of lakes or lagoons. But the
struggle for existence, and especially,
as we suppose the disadvantage of ter
restrial fertilization, at length drove
some Of these arboreous forms to high
or ground and different habits. The
minated spores no longer fell TO earth
for mere fortuitous union, but in the
fruit itself upon the trees the mating
Of the cells took place, and we have
suddenly real forest of coniferous
trees. To be sure, these earlier conifers
were not the same as those now living,
but they were in a measure like them.
ANY one familiar with the structure or
modern trees can recognize them. once
started they have been prominent In
earth's vegetation ever since. Slgnlh-
cant. though. these oldest conifers also
had abundant pith, One-third the total
diameter of the stem or more. 1t is
curious, too, that the earliest OF the
type did not after all have cones. The
fruit was more like that of the ginko,
the maidenhair tree of Japan, planted
now commonly in parks. Not until aft
er the close of the carboniferous dc
true cones appear, perhaps not until
the iurassic following.
But perchance the reader by this
time asks how we can tell about these
things so long gone by, what kinds or
trees they were and how they grew
and where. The answer is twofold-
first, we know past ages only by the
petrified remnants that lie buried IN
the rocks. like other fossils-shells, for
instance-of which we hear SO much,
and, second, we understand such fos-
sis only by comparison with existing
fora. For example, existing conifers
show q microscopic structure in their
wood. a structure absolutely definite.
When specimens Of petrified wood
come before us, especially if silicifed,
the structure is perfectly preserved,
and if coniferoUs we know it as well
as if we saw it grow. Now, fossil
wood is comparatively abundant, from
the devonian, and especially the car
boniferous. on down through all over
living formations. Fossil fruits and
flowers there also are, all too rare, but
now and then few are found, occa-
sionally even the fruit still hanging to
the branch on which it grew, so that
the identity is sure.
But the finest witnesses we have of
ancient forests are those which mark
the advent Of deciduous trees. The
broad, fiat leaf lends itself perfectly to
fossllization. It's imprint, once it falls
in favorable position, is stereotyped,
craven upon the rocks forever. Now,
the whole series OF cretaceOus rocks is
filled with leaf impressions, beginning
only few i'm the lowest stratum. The
upper layers are sometimes packed as
if the wind strewn foliage had condi-
toned i'm some sort the whole rocky
deposition. The leaf of course has van
ished. but its impress still remains, its
margin. its every vein and veinlet the
very glands sometimes that lent their
odors TO the air in days so long gone
by. Needless to say. many of these
forest leaves are strange. unlike any
now driven by the autumn winds, and
yet some of them are remarkably IA
miliar i'm appearance. Here are hazel
leaves and walnut leaves and poplar
leaves. You would have said that they
had but fallen from their twigs last
year You recognize them. They are
no doubt walnuts. haZels. poplars. Yet
they are not quite the leaves of our
modern trees The bOtanist would
write them different species Some
times the fossils Indicate genera no
longer eXtant on the continent where
the fossils lie. Thus our North Ameri-
can rocks afford Us cinnamon leaves in
rich abundance but there are no Gin
namons growing now on all this side
of the world. Our nearest representa-
tives are the laurels and the sassafras.
we have already in these chapters re-
ferred TO the tulip tree Il glorious tree,
but the only lone species of the genus
now on earth But in cretaceOus times
tulip trees dourished all over the north
ern world many species in this country
and i'm Europe, ranging south as far as
Italy and north as far as Greenland.
In fact. everything seems TO Indicate
that for our northern world ut least the
forests of cretaceous times were richer,
more varied. more extended and in ev-
cry way finer than those we know to-
day. These trees were the immediate
ancestors of those we know, the same,
yet not quite the same. Conditions on
the earth have changed since forests
were at their prime, the glory of the
world. Vegetation entered first upon
LIES scene and eliminated first. cul-