lectures on evolution-第4节

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circumstantial　evidence　alone；　for；　from　what　I　have　said；　you

will　understand　that　I　do　not　propose　to　discuss　the　question　of

what　testimonial　evidence　is　to　be　adduced　in　favour　of　it。

If　those　whose　business　it　is　to　judge　are　not　at　one　as　to　the

authenticity　of　the　only　evidence　of　that　kind　which　is　offered；

nor　as　to　the　facts　to　which　it　bears　witness；　the　discussion　of

such　evidence　is　superfluous。



But　I　may　be　permitted　to　regret　this　necessity　of　rejecting　the

testimonial　evidence　the　less；　because　the　examination　of　the

circumstantial　evidence　leads　to　the　conclusion；　not　only　that

it　is　incompetent　to　justify　the　hypothesis；　but　that；　so　far　as

it　goes；　it　is　contrary　to　the　hypothesis。



The　considerations　upon　which　I　base　this　conclusion　are　of　the

simplest　possible　character。　The　Miltonic　hypothesis　contains

assertions　of　a　very　definite　character　relating　to　the

succession　of　living　forms。　It　is　stated　that　plants；　for

example；　made　their　appearance　upon　the　third　day；　and　not

before。　And　you　will　understand　that　what　the　poet　means　by

plants　are　such　plants　as　now　live；　the　ancestors；　in　the

ordinary　way　of　propagation　of　like　by　like；　of　the　trees　and

shrubs　which　flourish　in　the　present　world。　It　must　needs　be　so；

for；　if　they　were　different；　either　the　existing　plants　have

been　the　result　of　a　separate　origination　since　that　described

by　Milton；　of　which　we　have　no　record；　nor　any　ground　for

supposition　that　such　an　occurrence　has　taken　place；　or　else

they　have　arisen　by　a　process　of　evolution　from　the

original　stocks。



In　the　second　place；　it　is　clear　that　there　was　no　animal　life

before　the　fifth　day；　and　that；　on　the　fifth　day；　aquatic

animals　and　birds　appeared。　And　it　is　further　clear　that

terrestrial　living　things；　other　than　birds；　made　their

appearance　upon　the　sixth　day　and　not　before。　Hence；　it　follows

that；　if；　in　the　large　mass　of　circumstantial　evidence　as　to

what　really　has　happened　in　the　past　history　of　the　globe　we

find　indications　of　the　existence　of　terrestrial　animals；　other

than　birds；　at　a　certain　period；　it　is　perfectly　certain　that

all　that　has　taken　place；　since　that　time；　must　be　referred　to

the　sixth　day。



In　the　great　Carboniferous　formation；　whence　America　derives　so

vast　a　proportion　of　her　actual　and　potential　wealth；　in　the

beds　of　coal　which　have　been　formed　from　the　vegetation　of　that

period；　we　find　abundant　evidence　of　the　existence　of

terrestrial　animals。　They　have　been　described；　not　only　by

European　but　by　your　own　naturalists。　There　are　to　be　found

numerous　insects　allied　to　our　cockroaches。　There　are　to　be

found　spiders　and　scorpions　of　large　size；　the　latter　so　similar

to　existing　scorpions　that　it　requires　the　practised　eye　of　the

naturalist　to　distinguish　them。　Inasmuch　as　these　animals　can　be

proved　to　have　been　alive　in　the　Carboniferous　epoch；　it　is

perfectly　clear　that；　if　the　Miltonic　account　is　to　be　accepted；

the　huge　mass　of　rocks　extending　from　the　middle　of　the

Palaeozoic　formations　to　the　uppermost　members　of　the　series；

must　belong　to　the　day　which　is　termed　by　Milton　the　sixth。

But；　further；　it　is　expressly　stated　that　aquatic　animals　took

their　origin　on　the　fifth　day；　and　not　before；　hence；　all

formations　in　which　remains　of　aquatic　animals　can　be　proved　to

exist；　and　which　therefore　testify　that　such　animals　lived　at

the　time　when　these　formations　were　in　course　of　deposition；

must　have　been　deposited　during　or　since　the　period　which　Milton

speaks　of　as　the　fifth　day。　But　there　is　absolutely　no

fossiliferous　formation　in　which　the　remains　of　aquatic　animals

are　absent。　The　oldest　fossils　in　the　Silurian　rocks　are　exuviae

of　marine　animals；　and　if　the　view　which　is　entertained　by

Principal　Dawson　and　Dr。　Carpenter　respecting　the　nature　of　the

Eozoon　be　well…founded；　aquatic　animals　existed　at　a

period　as　far　antecedent　to　the　deposition　of　the　coal　as　the

coal　is　from　us；　inasmuch　as　the　Eozoon　is　met　with　in

those　Laurentian　strata　which　lie　at　the　bottom　of　the　series　of

stratified　rocks。　Hence　it　follows；　plainly　enough；　that　the

whole　series　of　stratified　rocks；　if　they　are　to　be　brought　into

harmony　with　Milton；　must　be　referred　to　the　fifth　and　sixth

days；　and　that　we　cannot　hope　to　find　the　slightest　trace　of　the

products　of　the　earlier　days　in　the　geological　record。　When　we

consider　these　simple　facts；　we　see　how　absolutely　futile　are

the　attempts　that　have　been　made　to　draw　a　parallel　between　the

story　told　by　so　much　of　the　crust　of　the　earth　as　is　known　to

us　and　the　story　which　Milton　tells。　The　whole　series　of

fossiliferous　stratified　rocks　must　be　referred　to　the　last　two

days；　and　neither　the　Carboniferous；　nor　any　other；　formation

can　afford　evidence　of　the　work　of　the　third　day。



Not　only　is　there　this　objection　to　any　attempt　to　establish　a

harmony　between　the　Miltonic　account　and　the　facts　recorded　in

the　fossiliferous　rocks；　but　there　is　a　further　difficulty。

According　to　the　Miltonic　account；　the　order　in　which　animals

should　have　made　their　appearance　in　the　stratified　rocks　would

be　thus：　Fishes；　including　the　great　whales；　and　birds；

after　them；　all　varieties　of　terrestrial　animals　except　birds。

Nothing　could　be　further　from　the　facts　as　we　find　them；　we　know

of　not　the　slightest　evidence　of　the　existence　of　birds　before

the　Jurassic；　or　perhaps　the　Triassic；　formation；

while　terrestrial　animals；　as　we　have　just　seen；　occur　in　the

Carboniferous　rocks。



If　there　were　any　harmony　between　the　Miltonic　account　and　the

circumstantial　evidence；　we　ought　to　have　abundant　evidence　of

the　existence　of　birds　in　the　Carboniferous；　the　Devonian；　and

the　Silurian　rocks。　I　need　hardly　say　that　this　is　not　the　case；

and　that　not　a　trace　of　birds　makes　its　appearance　until　the　far

later　period　which　I　have　mentioned。



And　again；　if　it　be　true　that　all　varieties　of　fishes　and　the

great　whales；　and　the　like；　made　their　appearance　on　the　fifth

day；　we　ought　to　find　the　remains　of　these　animals　in　the　older

rocksin　those　which　were　deposited　before　the　Carboniferous

epoch。　Fishes　we　do　find；　in　considerable　number　and　variety；

but　the　great　whales　are　absent；　and　the　fishes　are　not　such　as

now　live。　Not　one　solitary　species　of　fish　now　in　existence　is

to　be　found　in　the　Devonian　or　Silurian　formations。　Hence　we　are

introduced　afresh　to　the　dilemma　which　I　have　already　placed

before　you：　either　the　animals　which　came　into　existence　on　the

fifth　day　were　not　such　as　those　which　are　found　at　present；　are

not　the　direct　and　immediate　ancestors　of　those　which　now　exist；

in　which　case；　either　fresh　creations　of　which　nothing　is　said；

or　a　process　of　evolution；　must　have　occurred；　or　else　the　whole

story　must　be　given　up；　as　not　only　devoid　of　any　circumstantial

evidence；　but　contrary　to　such　evidence　as　exists。



I　placed　before　you　in　a　few　words；　some　little　time　ago；　a

statement　of　the　sum　and　substance　of　Milton's　hypothesis。

Let　me　now　try　to　state　as　briefly；　the　effect　of　the

circumstantial　evidence　bearing　upon　the　past　history　of　the

earth　which　is　furnished；　without　the　possibility　of　mistake；

with　no　chance　of　error　as　to　its　chief　features；　by　the

stratified　rocks。　What　we　find　is；　that　the　great　series　of

formations　represents　a　period　of　time　of　which　our　human

chronologies　hardly　afford　us　a　unit　of　measure。　I　will　not

pretend　to　say　how　we　ought　to　estimate　this　time；　in　millions

or　in　billions　of　years。　For　my　purpose；　the　determination　of

its　absolute　duration　is　wholly　unessential。　But　that　the　time

was　enormous　there　can　be　no　question。



It　results　from　the　simplest　methods　of　interpretation；　that

leaving　out　of　view　certain　patches　of　metamorphosed　rocks；　and

certain　volcanic　products；　all　that　is　now　dry　land　has　once

been　at　the　bottom　of　the　waters。　It　is　perfectly　certain　that；

at　a　comparatively　recent　period　of　the　world's　historythe

Cretaceous　epochnone　of　the　great　physical　features　which　at

present　mark　the　surface　of　the　globe　existed。　It　is　certain

that　the　Rocky　Mountains　were　not。　It　is　certain　that　the

Himalaya　Mountains　were　not。　It　is　certain　that　the　Alps　and　the

Pyrenees　had　no　existence。　The　evidence　is　of　the　plainest

possible　character　and　is　simply　this：We　find　raised　up　on　the

flanks　of　these　mountains；　elevated　by　the　forces　of　upheaval

which　have　given　rise　to　them；　masses　of　Cretaceous　rock　which

formed　the　bottom　of　the　sea　before　those　mountains　existed。

It　is　therefore　clear　that　the　elevatory　forces　which　gave　rise

to　the　mountains　operated　subsequently　to　the　Cretaceous　epoch；

and　that　the　mountains　themselves　are　largely　made　up　of　the

materials　deposited　in　the　sea　which　once　occupied　their　place。

As　we　go　back　in　time；　we　meet　with　constant　alternations　of　sea

and　land；　of　estuary　and　open　ocean；　and；　in　correspondence　with

these　al