Origin of Species Variorum

→ epoch; and that certain land and fresh-water shells have remained nearly the same, from the time when, as far as is known, they first appeared. 1872

period, although no explanation can be given of this fact. 1866

epoch. 1869

→ OMIT 1869 1872

progressed in organisation, 1866

→ progressed in organisation since even 1869 1872

since that most ancient of all epochs 1866

→ epoch; 1869 1872

formation of Canada; 1866

→ could be better fitted 1869 1872

better 1866

↑ 1 blocks not present in 1859 1860 1861 1872; present in 1866 1869

It is no great difficulty that fresh-water shells, as Professor Phillips has remarked, have remained almost unaltered from the time when they first appeared to the present day; but in this case we can see that these shells will have been subjected to less severe competition than the molluses which inhabit the far more extensive area of the sea with its innumerable inhabitants.

→ likewise be fatal, if the above 1872

be fatal to my view if 1866

likewise be fatal to my view if 1869

→ the above Brachiopods 1872

Brachiopods 1866 1869

→ slight changes in their conditions. 1872

their changing conditions of life. 1866

the changing conditions of life. 1869

→ really know how old 1869 1872

have any sufficient knowledge of the antiquity of 1866

→ is, and at what period 1872

and of the periods when 1866

is, and at what periods 1869

→ whether organisation on the whole has advanced is 1866 1869 1872

is 1861

→ OMIT 1872

as I believe, 1861 1866 1869

→ ought to be ranked as 1872

are 1861 1866 1869

→ highest: 1861 1872

to be ranked as highest: 1866 1869

→ members of distinct types in the scale of highness 1872

in the scale of highness members of distinct types 1861 1866 1869

that certain Brachiopods have been but slightly modified from an extremely remote geological →epoch; and that certain land and fresh-water shells have remained nearly the same, from the time when, as far as is known, they first appeared. It is not an insuperable difficulty that Foraminifera have

not

not,

→OMIT as insisted on by Dr. Carpenter, →progressed in organisation since even the Laurentian →epoch; for some organisms would have to remain fitted for simple conditions of life, and what →could be better fitted for this end than these lowly organised Protozoa? ↑ Such objections as the above would be fatal to

any

view

view,

which

if it

included advance in organisation as a necessary contingent. They would →likewise be fatal, if the above Foraminifera, for instance, could be proved to have first come into existence during the Laurentian epoch, or →the above Brachiopods during the

lower Silurian

Cambrian

formations;

formation;

for

this

were proved,

case,

there would not have been time sufficient for the development of these organisms up to the standard which they

~~had~~

had

then reached. When

once

....

advanced up to any given point, there is no

necessity

necessity,

on the theory of natural

selection

selection,

for their further continued progress; though they will, during each successive age, have to be slightly modified, so as to hold their places in relation to →slight changes in their conditions.

All such

The foregoing

objections hinge on the question whether we →really know how old the world →is, and at what period the various forms of life first appeared; and this may

be boldly

well be

disputed.

The problem →whether organisation on the whole has advanced is in many ways excessively intricate. The geological record, at all times imperfect, does not extend far enough back, →OMIT to show with unmistakeable clearness that within the known history of the world organisation has largely advanced. Even at the present day, looking to members of the same class, naturalists are not unanimous which forms →ought to be ranked as →highest: thus, some look at the selaceans or

sharks

sharks,

from their approach in some important points of structure to

reptiles

reptiles,

as the highest fish; others look at the teleosteans as the highest. The ganoids stand

in- termediate

intermediate

between the selaceans and teleosteans; the latter at the present day are largely preponderant in number; but formerly selaceans and ganoids alone existed; and in this case, according to the standard of highness chosen, so will it be said that fishes have advanced or retrograded in organisation. To attempt to compare →members of distinct types in the scale of highness

seemed

seems

hopeless:

hopeless;

who will decide whether a

cuttlefish

cuttle-fish

be higher than a bee— that insect which the great Von Baer believed to be "in fact more highly organised than a fish, although upon another type"? In the complex struggle for life it is quite credible that crustaceans,

for instance,

....

not very high