Mineral Point tribune. (Mineral Point, Wis.) 1869-1938, 1878-05-15
Origin Of the Prairies.

Ao6O WAAAOu NAOC4S WAkAlOOt IlCOI lHtlIlks
Origin Of the Prairies.
The origin of the prairies is question
over which geologists have sEeculated
long and fruitlessly. They have accu-
mulated an immense mass of literature
upon the subject, but the disputed point
remains to-day as far from settlement
As ever. II is the opinion of Prof. Leo
Lesquereux, one of the most eminent
scientists, and undoubtedly our best
authority upon fossil and some branches
of recent Botany, that the absence of
trees upon the plains of the West, as in
the plains of South America, Europe,
and Asia, is owing to the presence in
the soil of an excessive amount of ul-
mic acid, and also to its impalpable
lineness. He believes that these tree
less plains were, in the early period Of
their formation, covered with confined
water. which gradually became invaded
by aquatic plants, sedges, rushes, grasses,
etc. The slow decomposition Of these
plants, mostly going on under water,
created deposit of soft, black mold.
largely impregnated with ulmic acid,
and, though neither true peat nor true
mold, partaking of the nature Of both.
The fineness of the particles composing
this mold caused it to DE packed in a
tight-pressed, compact mass, which,
when finally drained and dried, was left
almost impervious to the atmosphere.
In this last circumstance Prof. Lesquer-
eux finds one reason why trees have not
covered the prairies as they have other
lands. A free access of oxygen is es-
sential to the termination of seeds of
arborescent plants. This cannot pene-
trate and circulate through the close
mold of the prairies in sufficient guam
titles; hence their treeless condition. It
has been urged, by the opponents of
Lesquereux's theory, that trees will grow
successfully when planted upon the
prairies; but Lesquereux replies that
artificial planting changes the natural
conditions of the prairie-soil. BY exca-
waiting and agitating the mold. it is bro
ken up. and rendered light, and abund-
antly accessible to the oxygen of the
atmosphere.
In the presence Of large proportion of
ulmic acid in prairie-soil, Prof. Lesquer-
eux finds second reason for the absence
of arborescent vegetation. The lamar
&C, he says, is the only one of our native
species Of trees that can grow in peaty
soil. Prof. Alexander Winchell is one
who disputes this last assertion,-declar-
ing that the Willow, the Tupelo, the
Water-Oak, the American Arbor-Vite,
and other trees flourish in swamps and
under water,-and, in fact, in just such
conditions as were presented by the
prairies, according to Prof. Lesquereux,
in the process of their formation. 1t is
impossible, with the space at our COM
mand, to present even an abstract of the
arguments used by this scientist in the
advance of his hypothesis, and in its de-
Tense against antagonists; but his latest
paper on the subject is presented in the
first volume of Prof. Worthen's report
OH the Geological Survey of Illinois, and
contains his opinions in full.
Prof. Lesquereux considers that the
prairies have been altered, from the lev
ell outline they originally presented, by
the action of water; and offers plausible
1CNcOAS w pIONC WHO pOSltAOu. MA-
Hay declares that, to produce the ex-
treme inequality now existing liz the
surface of prairies, there must have
been q greater amount of denudatiOn
than can possibly be accounted for by
the conditions supposed by the
professor. He also adduces the presence
of coarse material, such as gravel and
coarse rock, in the prairie-mold, and the
absence of fossils in the soil and sub-soil
ofhigh prairie-lands, as evidences weigh
ing strongly against the theory of their
having been formed under water. In
conclusion, Mr.. Hay states: "That
some portions of the prairies, especially
those bordering our Great Lakes and
some of our rivers, have originally been
swamps, cannot be doubted; but that
they are destitute of trees, must be at
tributed to other causes. the absence of
which in other localities permits the
growth of trees alike on the finest or
coarsest, sweetest or the sourest SOIL"
The Extinction Of Species.
The extinction of many animals that
are known tn have. formerly existed on