New-York tribune., 1868-12-24
SCIENTIFIC LECTURES.
PROF. DAWSON BEFORE THE AMERICAN IN
STITUTE on THE PRIIfEVAL FLORA.


lectures before tho American Institute was delivered ny
President Dawson Of the McGl College OF Montreal last
evening and was illustrated by series of charts repre-
sentng vegetation in the periods OF the earths his
tory before tho creation Of man, revealed BY their
fossil remains.
President Dawson said An eminent authority has de-
fined geOogsts to be class Of amiabe and harmless en-
thuslasts who are happy aud grateful you will only
consent to give them an unlimited quantity OF that Which,
TO them, has perhaps, tho most value OF an thlngs,
namely, past time. confess to this definition OF geoo
gsts far my subject this evening concerned Tor
shall have TO make large demaDd upon your ith as 10
the extent OF tho past time aud shall hayetO ask you 20
give all Of It which you reasonably and cOnscien-
tousy may. Geology, indeed works strange revelations
and the gray rocks and hills themselves are tngs
primitive and unchanging not things eOpaiatVey,
odcn rocks that IN dim and ghostke procession recede
from view into the past Of an anlqltY, compared
with which all human antiquities are things of yesterday
The murmuring pines, and tie hemloek: bearded WIN
moss and IN garments green lndlstnct n tBe t@,ign
prophetic but they belong not 10 the forest pmeyai OF
the earths younger days though they may point back
ward TO persisted predecessors OF truly OLD dae, truly
primitive and geological antiquity, It IL 10 them that
Try to carry you back IN Imagination ths evening
awaken those snnbering ages and make tnen green
again IN youreyes ana yocaln y9ureais oa
thoughts these Old forests aud imagining Their strange
fantastic forms and the singular creatures that lived
beneath Their shade, we saii nhu onlSeNes III , nsw
world different from mat which we lnlabit, ana diner
nye planets each clothed with the peculiar fora and
Inhabited by the pee uar fanna Of distinct Bel!oSlc
worlds with nOthr connect them with each othersaYe
only certain simartes OF plan ana conception But when
view these several worlds as successive ana destined
the one 20 prepare the way for the other can perceive
relations OF the most remarkable and unexpected char
acter and have presented 10 rs long pOacted scheme
OF creation too vast TO DO cont aeu Oh w "a Jul Jul
planet &C any one period. ana representing WIN our
present fora all the possibilities OF vegetable existence
and all the uses present and past when plants can serve;
have selected as the subject OF ths lecture one small
department OF the vast .ld " fossil plants, depart
uent OF nccunr interest relating 10 the Oldest known
plants and which, special ana iayOilte sthdy OF my
own must eudeayor to make attractive 70 you; BuJ
must not rest cOntented with this, but n Justice 10
the subject must Try also To present II n an orderly
and systematicd dmauner. Unjust endeavor 10 give yOi
something IKE cOhLtc ShcltH Oh th5t pnhcNHal ~
fora which the subject or this lecture ana IN order 10
do this, must first say few words Oh the relations OF
their pnmeyal 1oia TO eNsuug pahisi a. hiii say
something OF their relations 10 the geologic lllue; 5d
sDne Of the more remarkable plants that hourshed in
that pnmeyal age; and 4t snail conclude Win nOCnB
OF the uses Oi this plueNa nora 70 vs. e pacucA
give yOu ~ possible, some idea Of the light which geology
aud how far back hey can De Traced ~ se99sc uiIv,
First, then, shah speak for the benefit OIL thGse Who
lions OF existing plants and tie relation Of the fossil Cra
them. Takn the whole OF the plants known To us, we
into two great series first that series O plants in which
we observe distinct flowers, and irnt containing seeds
proper seeds with ,he embryo OF Iathte plants Ihese
are Tic highest plants, aud cOutitute the plBuOgauOus
plants Of the b0tlnsr. Then We have great class OF
plants OF lower and humber organization. when are
destitute OF true hOWers' ana @hch IEsea ol p'o @
seeds, produce little microscope spores, lhtae
iTT The WI Whole vegeiablo Kingdom divided mo
these two great classes now, tShiI- u, ~, NJ ~
have FIRST that group Of plants 10 which all our trees ana
shrubs and the greater part OF our cultivated pants au
need oxOgens which have distinct plth, ana
wood and bark. This Is the highest group Ihcn we AaVea
class in which there Is no distinction Oi wood ana DARK,
repre sented in the tropical regions by the palms. and in
our climate by some OF the grasses These ale tue eha0-
gems And lastly, We have a. class IN winch te PIN,
L.rk aud wood are all composed OF similar maeraltho
gymnosperms represented here by our pines ana Ia the
tropical regions by TIE saeo mus the i,enogain. are ire
aGl.la tuf. IeDgprgUtgl
Tie oak maple tree, tho palm tree, and the pine Tree
fold divis0n--the aerogens, or ferns ana club
NOSES; tho anophytes or the common mosscs
and tho thallophytcs or lichens, fung ana seaWeed
Next let what relation these prmeya nora bear
t. those OF modern times Two relations are possible
classification altogether; and second which Is the true
suppo,ition that the whole hora OF the earh. from the
earliest geologic times comes under one clas.lea'ioi
This shows that, from the beginning OF gcOio2ic le, one
plan has been followed ont IN the construction Of 1c veg
eable kingdom, and that the whole vegetable kgdom
consists not OF the plants now lnS upon the eah Dut
includes all the plants that nave ever lyed upon ~
gain, there is another posslbihy that ihe primitive
fora may include representatives. OF All our 1uaefh
classes Of plants or ony some OF mem Inc i"et u,
on them, and those of medium grade
fora concerned Ine fossil plahs are NOT emery
exogcus ondOgens, but gymnospoims on the Other
hand the acrogens the highest group OF the crypoga
nous plants in our day were then TIE most abundant
The prneyal Old therefore embraced tha hlSher crytO
ofbin Of vegetation but that manifested by the prmeya
fora We should not have known the possibilities oi the
vegetable Kingdom either il It's hifieSt iaIAs vi rs
lowest ranks, but only IN the middle OF the scale
Next let us glance at the relations Of the primev hora 10
geologic time. The oldest rocks we know, the coz0,c
have afforded no plants, 80 far as We Know az Az Ih9
next stratum, the palcoLOlc, lhcHle lne oaeSt la.u
different hora and In the calnozole. vi modern poou
We have other h0ras IL Sthe paeolOc nOa only OF
paeozoio period the seaweeds have existed. In the
earlier periods the classes OF aerogens ana gYmnoseFms
far the cNOgcns and eudO-ens While Inc reverse
is the fact at the present day Inc warm anu MOST
climate OF portions OF the southern hemisphere NJ tue
present day, now have nora more v hoarg o;bcr
portions Of the earth Inc uniformity OF tIe
nora OF that early period indicates temperature nearly
uniform throughout the earth. AT present we nave ~
our atmosphere but a small quantity OF earoon.e ac!u
gas II We had more u Woue ,oun a. rAo ' ht g
more uniform, by preventing the ladatlon O1 neat from
the earth The carbon locked up IN our coal mines ahu
tnen @ SAsS ,p ~ REASON @ for e UNIFORMITY Of cuae on
the earth the paeDzoc PERIOD the nora OF tnaI Jay u
dleatng aud moist climate NeN ioOhiiS 10 tio
dora OF the plants, VIII turn to the calDOhlIcfous
period when there was vast amount OF NtEclatO", AZ
tcrward made fossil and becoming coal Ia mat moist
warm, but unwhOIesone atmosphere, Me p nno
the sisaria or sea.-tree one ot tnose mos! mosI
Here we htvo n large tall stalk, without branches,
covered with large leaves or perhaps divided INTO leW
tr OF the stalk and the OF tile leaves There arc
no trees in our latitude resembling it IN structure We
OF a certain nut that Is found around them Trees OF
to and three feet in diameter were not uncomnoh Iho
root Of this tree Ia more relnaikGOe even tha Us ste
l ing attracted the attention Ot SeO1SstS DeIoe tlc
stem and obtained tho name Of stigmara Ihese roots
are bfucated aud spread ont III reDarkaoly regular
wNy ali the little rootets spreading regularly as
leaves. These roots occur very often III the coal
formadOu without the Stenis; ana at nrst u
was supposed that they were the whole OF the plant
Ihr rsi process in the formation OF bed vi coal was
usually tho growth Of forest of sgillarii The next
class OF plants the calames. some one called upon
a botnnist, said had been shown his callinltles
aud fpllctes" These caamites were tie calamities
iI.nugherl They seem to have grown on muddy lais
along tho margin OF the Sglaran woods. resembling
hrakcs or mares tails and they are stl preserved III
conl formations IN large numbers The ealamltes seem
10 have preserved the garian forests from the ELECTS
-, Inv
fore the waters passed into the forests. The
calamitcs thus contributed very much To the
uurity OF our coal beds Applause.l The next plant
Is the lepldOdcndron, or scaic-trce, or slze
equal 10 the sglaria, resembling our ground pines or
I.Ii. .,1.l. A.l..iif I'm rllYr