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NOTICE OF TEETIAKY EOSSILS

PROM LABRADOR, MAINE, &c.,

AXiD

REMARKS ON THE CLIMATE OP CANADA,

W TFi NEWER PLIOCBNB OR PLBISTOCBNB PERIOD.

I am indebted to Capt. Orlebar, R.N., for a small collection of
fossils from the vicinity of Tertiary Bay on the coast of Labrador,
X locality in which similar collections were made several years
Hince by Adm^ Bayfield. They occur iu clay a little above high
water mark ; but the species present indicate a considerable
depth at the time of the deposition of the bed in which they are
contained, so that it cannot properly be regarded as merely a
raised beach. The species contained in the collection are as
follows; those found in the newer Pliocene of Canada being
marked with asterisks.

Balanus joorcatus.^

Spirorhis vitrea, attached to shells.*

Sp. carinata.

Bxccinum undatum^^

Aporrhais occidcntalis.

Natica, (fragincnL probably oi N. Clausa.)*

Saxicavd rugosa, var. Arctica.^

Tellina proxima, {calcarca) •'^

Actarie dliptlca.

Rhynconclla psittacca.^

Echinus granulatus.

IlijypotJioa catetmlaria, (altachei-l to sbclls) *

Lepralla pcrtusa.*

L. (not determined.)

Cythcrc.

The f^reater number of the above species have already been
recognised in t'ue tertiary days of Canada ; * but the following
cxceptionp are deserving of notice.

Spirorhis vitrea, has not been named in my previous papers;
but I now find, on comparison with the specimens from Labrador
and recent examples from Gaspe, that it is this and not Spirorbis
sinistrorsa as prtviously stated, that occurs in the tertiary beds at
Montreal and Quebec. It is at present a deep water species in
the Gulf of St. Lawronce and on the banks of Newfoundland.
Spirorbis carinata has not previously been observed in the ter-
tiary beds ; but is common on the coast of Labrador and Gaspb.f

Aporrhais occidentalism the American representative of the
" Pelican's-foot Spout-shell" of Britain, and rema'-kablo in the
adult state for its siug^ularly expanded outer lip, is a deep water
shell somewhat widely though not very abundantly distributed
on the American coast. 1 have specimens from Labrador, Sable
Islund, and Portland, where a very fine liviug specimen was
dredged for me last summer by Mr. Fcrrier.

ilaxicava ruyosa, occurs in the Labrador collection under the
form described r.s S. Arctica by Forbes and Hanley. Tliis form
\i not prevalent though sometimes seen among the Saxicavoe of
the St. Lawrence valley deposits, and at present is I think found
only in deep water. The intermediate specimens prove it to be
merely a variety of the common species.

Astarte clliptica is the common Astartc of the Gulf of St.

* Soe papers hy the author in Canadian Naturalist, Vols. 2 and 4.
t See paper on Spirorbes of the Gulf of St. Lawrence iu last number

•f this Jgurnal.

oil

^^^^-^

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msf tf

Z4:^^m^t'.y9u/jm

Lawrence at present. Great nuinueis Lave been dredged by Mr
Bell on the coast of Gaspo in about CO fathoms. Along with
them are found a few specimens having the characters of the
typical Astartc sulcata of Great Britain, aii'i others having the
characters of A. compressa, a species much more nearly related
than the others to the fossil A. Laurcntlana, though quite
distinct. I can recognise in the collections made by Mr. Bell and
myself all the above species or variclies, and in addition the J..
Arctica, which I have found only in the pleistocene beds near Port-
land. A. Laurcntiana and A. Arctica are without doubt distinct
species from Sulcata, but different views have been entertained
as to the others. The distinction based by some . ithors on the
cronulated or smooth margin, and on which the species A. Scotica
and A. Damuoniensis have been founded, is evidently worthless,
depending as it does on age ; but the distinctions of external form
and marking are apparently constant at all ages, and do not shade
into each other. Although therefore Dr. Gould and Mr.
Stimpson retain the name sulcata for all our American forms, I
think it admits of a doubt whether the same distinctions made by
Forbes and Hanley in Britain do not hold here. Mr. P. P. Car-
penter when in Montreal very kindly went over my collections
with me, and expressed himself satisfied that we have the forms
recognised in Britain as elliptica, sulcata, and conipressa, what-
ever their specific value. My impression at present is that coni'
^■ressa is a good species, but that sulcata and elliptica as we have
them may be varieties of one. It is curious that while A. Lati-
rentiana prevails exclusively iti the St. Lawrence deposits, the
modern species is found at Labrador ; and very possibly, especially
when we regard the more inland position and greater elevation o
tlie former, this indicates a difference of age in the deposits.

The clay attached to and in the interior of Capt. Orlebar's spe-
cimens is very rich in the minute Foraminifera. It contains
specimens of all the forms found in the clays of, Montreal and
described in my former papers, and in addition the following :
RotoUna ohlonga, Fig. 1.
Bulimina pupoidcs, Fig. 2.
B, auriculata ?

OrhuUna universal
Ttxtularia variabilis, Fig. 3.
Nbnionina Lahradorica^ N. sp. Fig. 4.
Truncatulina lohata Fig. 5.

- Jk rft^5**^CSlS^~

i\^ ^:^w^?'

All of these except one are well known hvmg species and a 11
except Textularia variabilis have been found in the Gulf o( St.
Lawrence. This last statement however could not have been
made but for specimens obtained from clay taken up by the
sounding leaa otf the coast of Anticosti, from depths varying
from 144 to 313 fathoms, and for which also I am indebted to
Capt Orlebar. In these soundings there also occur Globigenna
lulloides^ spreics world-wide in its distribution and iVoc?osa.t«
pynda, neither of which have as yet been found in Uie tertiary
beds of Canada. With these recent shells there is a C>/there like
C anqulata of the British seas, and numerous spicules of spou-
ses- there are also immense numbers of the round perforated
silicious shields of CuscinocZisd apparently the C. hncatns ax^d C.
radiatus of Ehrenberg. It is a remarkable and at present unac-
countable fact that while in the pleistocene beds there is a
great abundance of foramimfera, sponge spicules, and valves ot
cvthere imbedded in calcareous clays like those of the deep sound-
ings of the Gulf, the Coscinodisci and other diatoms arc abseut
or at least have not been recognised.

Fig. 1.

Fig. 2.
Fig. l.—Rotalina oblonga.
2. — Bulimina pupoides.
3. — Textularia variabiliis.

Fig. 3

Truncatulina lohata. The last species in the list is a little
parasitic foraminiferous shell adhering to shells, stones, and
zoophytes. It abounds in Mr. Bell's and Mr. Richardson's recent
collections from Gaspe, and since I observed it in Capt. Orlebar's
collection, 1 have found it also at Montreal. It is the Nautilus
stellaris of Fabricius.

The Nonionina which I name iV. Lahradonca, and which is
found both recent and fossil, is a very beautiful species. It is
pc.fecily equilateral, smooth and remarkably white and lustrous.
It is most readily characterised by the great expansion of the last
chamber, which spreads laterally and extends in two lobes on

wwms^i^wm^m t = f / » ir/joFa

either side of the earlier whorls. When seen f.^m one side it
resembles Rotalina turgida, for which indeed I mistook it at
first ' but when viewed in front it is seen to be equilateral and to
have the characteristic .eptal aperture of Nonionina It is about
equal in size to iV. umbiUcatula, and has the last chamber
nflated even in young shells.

i.-

Fi". 4.

Ficc.

viv, 4..— iVbniont/ia Labradorka, X. sp.
r>. '■Truncatulina Jo''ai-'.

The Forar/iniferafron- vhedoci^or parts of the Gulf arc usually
of small size, and this appli.-i, also to those from the pleistocene

of Labrador.

In the past summer another deposit of pleistocene shells was
discovered by Sir W. E. Logan at the Mingan Islands, Labrador.
The specimens obtained from it consist of Mya arenaria and
"""llina pvxima in hn'd sand, and have the aspect of a littoral
aeposlt corresponding to the " saxicava sand" of the vicimty of

Montreal.

2. Portland, Maink.

In last August I enjoyed some opportunities of examining
the tertiary deposits at and near Portland, and also at Pond Cove,
Cape Elizabeth, where a small patch of thi. deposit occurs nearly
at the level of the sea. At the south end of the city of Portland,
in a deep railway cutting, the tertiary beds arc well seen, and
consist, in ascending order, of boulder clay, fossiliferous stratified
clay and sand, and stratified sand and gravel. These beds appear
to be very irrogular, being entangled in ledges of metamorphic
rock, which sometimes ri«c through them. The distinction between
the deeper water and shallow water parts of the deposits is in

'^<5v

Vvl£, • ■ ^iSirli^^^'^^^^i I

consequence less strongly marked than at Montreal, but is indi-
cated by beds containing Mytihis eduUs alone, overlying those
■Nvhich contain shells chavactcristic of the open sea. At Capo
Elizabeth the pleistocene claya occupy depressions between ridges
of slate. At the only place wheru I observed fossils, the deposit
is a hard gray stony clay containing a mixture of deep sea and
littoral shells. The bivalves are mostly in detached valves and
often on edge, as if the bed had been subjected to the pressure of
ice after its deposition.

The fossils observed in the above mentioned beds are as fol-
lows, — those common to Portland and the S:. Lawrence valley
bcino: marked with asterisks :

Balanus crcmttus/''

Fusus deccmcostatus, (var. horealis,)

Bucclnum undalum^^

Fusus scalarifonnis,

Natica clausa,-'^

Mjjtllus cdidls;'''

Mactra ovalis,

Saxicava rugosa;'''

Astarte dUptlcn,

A. comprcssa,

A, arctica,

Tdllna j^rbxlma,^'^

Pectcn Islandiciis/^-

My It tnincata^''

Nucxda Jachsoni,

AphroditG Grocnlandlca,

Lepndla variolosa,

L. BcIUi^

Memhranlpora, (undetermined.)

The assemblage of shells in the above list cannot be said to
indicate any very great change of climate, though more like that
of the Gulf of St. Lawrence than of Portland at present. With
the exception of Astarte arctica not now found on the Ameri-
can coast, and Niicida Jacksoni which is possibly extinct, they are

* A new species, now living in the Gulf of St. Lawrence, and de-
eribed in the Report of the Geological Survey of Canada for 1858.

^■'mrsLi^^smmM B ' ■, /m ir/jks

.11 couunon Aniovican spcio. It is cunoa. iha. m t^e -llect on
of the Canadian Goologicai Survey, the group of shells obtamed
by Mr. Bell and Mr. Richardson in dredging on the north coast
o? ol^pe in about GO fathoms, is almost precisely that of those

Portland beds c, t .vrence tortiarieB, it will be seen

Oh comparison NYilh tne St. Lav. renctterii<un;.,

that 8 out of 19 specie, are distinct. It is further to be observed
t^^a f^l <lcc.Ltatu. replaces the closely allied ^. .oma«s.
that Sa.lca.a ru.osa i. much loss abundant that tn o c.
Astartes appear instead of .4. Laurentmnn, and tha %^.?«.^
tduUs isof rge size and of the ordinary form, ihese d. lerence.
are llvcver Trobably nothing n.oro thau the effects of the more
oceanic position of the Tortland beds, as co.nparcd with the
old inland soa of the St. Lawrence valley, and it will be observed
that in respect to the Astavtes the Portland bods correspond
.vith thoseof Labrador,. The loss elevation of the Portland bed.
however renders it probable that they arc somewhat newer than
those of the St. Lawrence valley rnd of Lake Champlain

In the cabinet of Dr. Jackson of Boston, I had an opportunity
of examining a collodion of about 14 species obtained by him
from the beds on the Pressumpset Kivor, doscribcd ma.y years
a<.o bv Professor Uitchcock and Dr. Jackson. In this collection
^vliile several of the shells found at Portland are absent, 1 found Leda
PoTtJandlcar^ Nnada proximo, Terehratula septcr^tnonahs,
Mya arenarkt, and the carapace of a crab.

3. OCCURRENCE CF ERESII WATER SHELLS IN THE PLEIS-
TOCENE BEDS.

I owe to the kindness of A. Di.kson, Esq, additional collections
of the fresh water shells and the sands containing them from Pake.i-
hamt together with a communication from a gentlemen of that
place citing a section of lue deposits as seen in a deep road
cutting! Tho arrangement is as follows in descending order :

Sand and surface soil, aboat, 10 feet

,„ 10 "

Clay,

» Dr Gould iuformB me that he is now satisfied of the correctness of
the identification of this shell by Mr. Wood with the species L truncata
of the British Pleistocene and of the artic seas, where it has ben

living.

t See my parer. Canadian Naturalist. Vol. n .

m -fjai

Fine gray sand (shells of Valvata^ «Src.) 2 incboi

r» . . . , 1 foot

Clay, jj

Gray sand, laminated {Tellina Grtenlandica),.. 3

Clay, ;•• ^

Lig'bt gray sand {Valvata, Cyclas, PaluJ'na,

Planorhls and Tellina), 10

Clay, l''"«^^2 "

Brown sand and layers of clay, {Planorhis and

C^chs), ^

The spacies were the same with those described in my previous
papers, and the only marine shell is TclUna Gmnlandlca, a
species now found farther up in oi . estuaries than mc-st others.

Mr. Dickson informs mc that a similar case occurs near Clar-
cnceviUe, about four miles tVoui the United States frontier, and
at an elevation of about ten feet above La^ie Charaplain. Speci-
mens from this place contain large shells of Unio rectus and U
ventricosus, the latter with the valves cohering, and a Lymnea.
Intimately mixed with these in sandy clay are valves of TelUna
Grocnlandica and Mya arenuria.

I record these facts, without pledging mys.lf to the conclusion
that thc.o deposits really mark the margins or river estuaries of
the old rieistoeenc sea of Canaaa ; though they wdl certainly bear
that interpretation. In farther connection with these facts, and
in relation also to the quest'ou why marine fossils have not been
found west of Kingston, Mr. Dickson informs me that fossil capelin
are found on the Chaudiorc Lake, 183 feet above Lake St. Peters,
on the Madawaska 20C. feet, and at Furt Coloiige Lake 30^ feet
above the same level, a very interesting indication of the gradual
recession of the capelin spawning grounds, from this last high
elevation to Jie level of the more celebrated locality of these fossils
at Green's Creek. Farther, th; ougiiout the Counties of Renfrew,
Lanark, Carlton and Leeds, the marine deposits rise to an ele-
vation of 425 feet, or nearly the same with that which they reach
on Montreal Mountain ; but while this elevation would with the
present levels of the country carry a deep sea to the head of Lake
Ontario, no marine fossils appear to have been found on the banks
of that lake. Was the depression of the later pleistocene period
limited to the country east of Lake Ontario, or have the marine
deposits of the upper St. Lawrence liitherto escaped observation

afej*

/9 tr/is*

or been romovcd by denuding agencies. The question awaits
further explorations for a satisfa 'tcry answer.

In the mean time it is certain that the boulder clay and
deposits corresponding in arrangement and mechanical character
to the Leda clay and Saxicava sand of the Lower St. Lawrence,
exist in these more western regions, though they have not boen
found to contain marine fossils.

4. CLIMATE OF CA.<ADA IK THE PLEISTOCENE ?ERIOL.

The climate of this period and the causes of its difference from
that which now obtains in tho northern liemispherc, have Leen
fertile subjects of discussions and controversion which I have no
wish here to re- open. I merely propose to stat^ in a manner
Jevel to the comprehension of the ordinary read. ho facts of
the case in so far as relates to Canada, and an importa.-t infc-
once to which they appear to me to lead, and which if sustained
^vill very much simplify our views of this questi u

Every one knows that, the means and extremes oi" annual tem-
perature differ mucii on the opposite sides of the Atlantic. Tho
isothermal line of 40° for example parses from the south side of
the gulf of St. Lawrence, sUiits Iceland and reaches Europe near
Drontheim in Norway. This fact, apparent as the result of obser-
vations on the temperature of the land, is equally evidenced by
the inhabitants and physical phenomena of the sea. A large pro-
portion of the shell fisli inhabiting the gnlf of St. Lawrence and the
coast thence to Cape Ccd, occur on both sides of tho Atlantic,
but not in the same latitudes. The marine i-iuna of Capo Cod
is parallel in its prevalence of boreal forms with that of the south
of Norway. In like manner die descent of icebergs from the
north, the freezing of oays and estuaries, the drifting and -ushing
of stones nnd boulders by ice, are witnessed on the Ameriean coast
in a manner uot parallelled in corresponding latitudes in Europe. U
follows from this that a collection of shells frc. ; any given latitude
on the coasts of Europe or America, would bear testimony to tho
existing difference of climate. Tiie geologist appeals to the same
kind of evidence with reference to tho climate of the later tertiary
period, and let us enquire what is its testimony.

The first and most general answer usually given, isthat^the
pleistocene climate was colder than the modern. The proof of
this in Western Europe is very strong. The marii.c fossils of this

-mo/L

period in Britain arc more like the existiiig fauna of Norway or
of Labrador than the present fauna of Britain. Great evidences
exist of driftao-e of bouU.lcrs by ice, and traces of glaciers on the
hiffher hills. ^In North America ll<o proofs of a rigorous climate
■md especially of the transport of boulders and other materials
by ice are equally good, and the marine fauna all over Canada
and New England is of boreal type. In evidence of these facts
I may appeal to the papers and other publications of Sir C. Lyel
and Professor Ramsay on the formations of the so called glacial
period in Europe and Amcrica,^^ and to my own previous papers
on the tertiaries of Canada.

Admittino- liowever that a rigorous climate prevailed in the
pleistocene period, it by no moans follows that the change has
been equally great in different localities. On the contrary while
a great and marked revolution has occurred in Europe, the evi-
dences of f:uch change are very much more slight in America.
In short, the causes of the coldness of the pleistocene seas to
some extent still remain in America, while they must have dis-
appeared or been modified in Europe.

If we enquire as to these causes as at present existing, wc find
them in the distribuMon of ocean currents, and especially n the
great warm current of the gulf stream, thrown across from Ame-
rica to Europe and in the Arctic currents bathing the coasts of
America. In connection with these we have the prevailing wes-
terly winds of the temperate zone, and the great extent of land and
shallow seas in Northern America. Some of these causes are
absolutely constant. Of this kind is the distribution of the winds
depending on the earth's temperature and rotation. The courses
of the currents arc also constant, except in so far as modified by
coasts and banks; and the direction of the drift-scratches and
transport of boulders in the pleistocene both of Europe and Ame-
rica, show that the arctic currents at least have remained un-
chan-rcd. But the distribution of land and w.atcr is a variable
element, since we know that in the period in question nearly all
northern Europe, Asia and America were at one time or another
under the waters of the sea, and it is consequently to this cause
ihat wc must mainly look for the changes which have occurred.

* LycU's travels in North America, Ramsay on the glaciers of Wales,
tmd on the glacial phenomena of Canada. See also Forbes on the fauna
and flora in the British Islands, in Memoirs of geological survey

Such changes of level must, as has been long since sliown by
Sir Charle? Lyell, modify and change climate. Every diminu-
tion of the lan(i in arctic America must tend to render its climate
less severe. Every diminution of land in die temperate regions
must tend to reduce the mean temperature. Every diminution
of land any where must tend to diminish the extremes of annual
temperature ; and the condition of the southern hemisphere at pre-
sent shows that the disappearance of the great continental masses
under the water would lower the mean temperature but render
the climate much less extreme. Glaciers might then exist in
latitudes where now the summer heat would suffice to melt them^
as Darwin has shown that in South America glaciers extend to
the sea level in latitude 40° 50' ; ard at the same time the ice
would melt more slowly and be drifted farther to the southward.
Any change that tended to divert the arctic currents from our
coasts would raise the temperature of their waters. Any change
that would allow the equatorial current to pursue its course through
to the Tacific or along the great inland valley of North America,
would reduce the British seas to a boreal condition.

The boulder formation and its overlying fr)ssilifcroiis beds
prove, as I have in a previous paj^er endeavoured to explain with
regard to Canada, and as has been shown by other geologists in
the case of other region?, that the land of the northern hem-
isphere un.'orwent in the later tertiary period a great and gra-
dual depression and then an equally gradual elevatior. Every
step of this process would bring its modifications of climate, and
when the depression had attained its maximum there probably
Avas as little land in the temperate regions of the northern hemis-
phere as in the southern now. This would give a low mean tem-
perature and an extension to the south of glaciers, more espe-
cially if at the same time a considcrabh arctic continent remained
above the waters, as seems to be indicated by the effects of ex-
treme marine glacial action on the rocks under the boulder clay.
These conditions, nctually indicat'jd by the phenomena tliem-
selves, appear quite sufficient to account for the coldness of the
seas of the period, and the wide diffusion of the gulf stream caus-
ed by the subsidence of Amciican land, or its entire diversion into
the Pacific basin*, would give that assimilation of the Amciican

• This is often excluded from consideration, owing to the fact that
the marine fauna of the gulf of Mexico differs almost entirely from that
of the Pacific coast; but the question still remains whether thisdittc-
rencc existed in the later tertiary period, or has been establisliea in the
modern epoch, us a consequence of changed physical conditions,

and European climates so characteristic of the time. The chmale
of western Europe in short, >.ould under such a stateof things be
greatly reduced in mean temperature, the climate of America
would suffer a less reduction of its mean temperature, but would
be much less extieme than at present ; the general effect being
the establishment of a more equable bit lower temperature
throughout the northern hemisphere. It is perhaps necessary to
add that the existence on the land, during this period of depres-
sion, of large elephantine mammals in northern latitudes, as for
instance the Mammoth and Mastodon, does not contradict this con-
clusion. We know that these creatures were clothed in a manner to
fit them for a cool climate, and an equable rather than a high tem-
perature was probably most conducive to their welfare, while the
more extreme climate consequent on the present elevation and dis-
tribution of the land may nave led to their extinction.

The establishment of the present distribution of land and water,
giving to America its extreme climate, leaving its seas cool and
throwing on the coasts of Europe the heated water of the tropics,
would thus afreet but slightly the marine life of the American
coast, but very materially that of Europe, producing the result so
often referred to in these papers, that our Canadian Pleistocene
fauna differs comparatively little from lliat now existing in the
gulf of St. Lawrence, though in so far as any difference subsists
it is in the direction of an arctic character. The changes that
have occurred are perhaps all the less that so soon as the Lau-
rentidc hills to the north of the St. Lawrence valley emerged from
the sea, the coasts to the south of these hills would be effectually
protected from the heavy northern ice drifts a'ld from the arctic
currents, and would have the benefit of the full action of the
summer heat, advantages which must have existed to a less extent
in western Europe.

It is farther to be observed that such subsidence and elevation
would necessarily aftord great facilities for the migration of arctic
marine animals, and that the difference between the modern and
newer pliocene faunas must be greatest in those localities to which
the animals of temperate regions could most readily migrate after
the change of temperature had occurred.

It has been fully shown by many previous writers on tliis sub-
ject, that the causes above referred to arc sufficient to account for
all the local and minor i)henomena of the stratified and unstra

;iTfa

tified drifts, and for the driftage of boulders and other matemls,
and the erosion that accon^panied its deposition. Into these
subjects 1 do not propose to enter; my object in these remarks
be4 merely to give the reasons for my belief stated m previous
papers on this subject, that the difference of climate between
pleistocene and modem Canada, and the less amount of that diffe-
rence relatively to that which has occurred in western Europe
may be explained by a consideration of the changes of level which
the structure and distribution of the boulder clay aud the over-
lying fossilifcrous beds prove to have occurred.