, 1873-06-22


ed b., Dumecil, and the suspicious of cuyier
that all 6iredons arc merely 1aryal salanlandeIs.
SCIENTIFIC VALUE OK THESE DISCOVERIES,
This wild Western country, SO long regarded
as q desert devoid of human interest, is now, BY
toric ground onoo peopled with the most gro
tesquo and diverse forms Of animal life; . Won
derland OF dragons, monsters, and chlmeras
dire. All tho great additions to the Museum OF
Yale College, SO far as vertebrate fosslls are
saven years. Great as is the value of
such accumu1Ations Of new and rare palm-
ontologica1 specimens, the most important
result is in the materials they afford for eluci-
dating the worlds early history. It is the labor
identify, class and describe theEo FOSSILS. Every
bone IS the subject Of study, and tho deduc-
tions are Set forth in printed documents, in
which every word is weighed as II it belonged
to new goepel. To Prot. Marsh, who is tirm
and full believer in the Development hypothe-
s1s, every ewly-found fossil is another link IN
the long chain leading from tho lowest to the
highest representatives Of ranimal life. These
Western discoveries haGo largely consisted OF
those intermediate forms which were most
Of the highest value in the science Of compare
tive snatomy. In the number and variety OF
these extinct animals We have material far more
important than anything Europe has to offer,
for the solution OF the questions that pertain to
4 brief glance at the geology Of the Rocky
Mountain region elbows that it IVES once covered
by the sea, at the period designated by geolog1sts
as the cretaceous, when the great formation OF
chalk took place 1T the bottom Of this ocean. In
long subsequent ages, when this region had
emerged from the sea, It continued several I'M
mense lakes Of fresh water. Tho positions these
occupied are designated as "basins." When
lake basins are spoken OF in this letter, no exist
ing bodies Of water are referred to, but merely
the geological formation left by the deposition
IN these lakns OF the soil washed down into them
through long ages from the surrounding hills.
These basins are now, with the great elevation
Of that part Of the continent, lifted to position
several thousand feet above sea-leyel. In
carried away by denudating atmospheric in
duences, the surface worn down and washed
away by the storms OF another series OF ages,
and the material carried away by the rivers that
rise in the Rocky Mountains, to lay new floors in
modern OCEANS But some of the deposits in
tho cretaceous ocean, and some Of those in the
fresh-wateT lakes, where they are capped with
harder material than the average, yet remain
The "buttes are Immense masses OF this kind,
left standing in the plains, with rough, pEeclp-
itous sides, hundreds OF feet high. Their tops
mark the level Of the deposit. Many Of them
are benches resting against the adjacent Inoun-
tainB. Out Of their sides, frequently IN almost
inaccessible positions, fossils partially denuded
are occasionally Eoen sticking out. The
Yale party counted in ono instance. from
single point OF view, eleven fossil tur-
Ties thus exposed. In tho district known as
Bad Lands, near Fort Bridger, these rocky
masses, penetrated by deep rasiues, and eroded
to various nights and shapes, make region OF
peculiar W1dnoss eud desolatlon.
EocESE FOSSILS.
The Yale College party Of 1870 discovered and
traced for 800 miles the basin Of q vast ancient
lake. It is between the Rocky Mountains on
the east and the Waeatoh ranges on the west;
Its dimensions arc at least 3U0 miles north and
south, and 900 east and west.
Fort Bridger, in Wyoming, from which the
party started, is situated at the northern base OF
the Uintah Mountains, about 1000 feet above
the sea. The surrounding plain is part OF
colored clays and soft sandstones Of tertiary age,
the deposits in ono OF the great tresh-
water lakes. that replaced the cretaceous sen
from which tho uass of the Rocky Mountains
emerged. Remnants OF the strata removed may
be seen at various points around; some IN the
shape Of flat, isolated buttes, and others forming
benches, resting horizontally against the side OF
the mountains. These fragments serve to show
the great original thickness Of this lake deposit,
which cannot, apparently, have been less than
$500 feet, and may have been much greater:
few miles to the southeast these soft strata have
still further escaped denudation, and are wealth.
cred out into fantastic conich forms, Iesem-
bling those Of the !" Mauvaises Torres" forma-
non OF NebfasKa and Dakota. 1Aese ollt1s az
known in this region rs the Grizzly Buttes," :"
and through them lay the route to the Green
River.
A careful examination Of this " Bad Land u
district soon indicated that fossil, vertebrate
fauna Of peculiar interest was hero entombed.
Here reptilian life had evidently been abundant,
and was represented by all its principal forms.
| Crocodilians, tortoises, lizards, serpenta, and
fishes had s1armed in the waters Of this tropca!
like; while Tapiroid mammals. with many
| smaller quadrupeds, had lived near it's borders.
the "Grizzly Buttes,'' which offered so inviting
field, that . fortnight WAS devoted to their e1-
ploration, resulting in the discovery Of 4 large
number Of extinct vertebrates new to science.
This basin is OF eocene formation, and is the
oldest OF the Rocky Mountain ancient lake
basins. It rests directly on tho cretacoous for
nation. In this eoceue basin the genus Dinoce-
rus 2lons occurs.