Origin of Species Variorum

→ groups are 1872

these orders have been 1861 1866

orders are 1869

→ of brachiopods, and the fact that our 1872

at the present day of the lowest molluscs, more especially as the 1861

at the present day of the lowest molluses, more especially as the 1866

of the lowest molluscs, and the fact that our 1869

→ at any two periods of 1872

of 1861 1866 1869

→ world: if, for instance, 1872

population of the world 1861 1866

world 1869

→ OMIT 1872

two periods: if, for instance, at the 1861 1866 1869

→ is 1869 1872

will apparently for ever be 1861 1866

→ OMIT 1869 1872

under one important point of view 1861 1866

→ OMIT 1869 1872

the case of 1861 1866

→ by the indigenes, we must believe, that 1872

we may believe, 1861

we must believe, 1866 1869

→ OMIT 1872

that in the course of time 1861

in the course of time 1866 1869

→ in the course of time become 1872

become 1861 1866 1869

→ the fact that 1872

what we see now occurring in New Zealand, and from 1861

the progress of this displacement in New Zealand, and from 1866

OMIT 1869

→ well doubt whether, 1869 1872

doubt, 1861

well doubt, 1866

→ stand much higher in the scale 1869 1872

may be said to be higher 1861 1866

in their own class, might beat

the

....

cephalopods

cephalopods,

the

highest

molluses;

molluscs;

and such crustaceans, though not highly developed, would stand very high in the scale of invertebrate

animals

animals,

if judged by the most decisive of all trials— the law of battle. Besides these inherent difficulties in deciding which forms are the most advanced in organisation, we ought not solely to compare the highest members of a class at any two

distant

....

periods— though undoubtedly this is one and perhaps the most important element in striking a balance— but we ought to compare all the members, high and low, at the two periods. At an ancient epoch the highest and lowest

molluscs,

molluses,

molluscoidal animals,

namely, cephalopods and brachiopods, swarmed in

numbers:

numbers;

at the present time both →groups are greatly reduced,

whereas

whilst

other

others,

orders,

....

intermediate in

grade of

....

organisation, have

been largely

largely

increased; consequently some naturalists

have

....

maintained

maintain

that

molluses

molluscs

were formerly more highly developed than at present; but a stronger case can be made out on the

other

opposite

side, by considering the vast reduction →of brachiopods, and the fact that our existing cephalopods, though

....

few in number, are more highly organised than their ancient representatives. We ought also to

consider

compare

the relative proportional numbers →at any two periods of the high and low classes

throughout

the →world: if, for instance, at

any

the

→OMIT present day

there be

....

fifty thousand kinds of vertebrate

animals,

animals

and

exist, and

if we knew that at some former period only ten thousand kinds

had

....

existed, we ought to look at this increase in number

the highest class, which implies a great displacement of lower forms, as a decided advance in the organisation of the

world,

whether

the

higher

the

lower

vertebrata

had

thus

largely

increased.

can

thus see how hopelessly difficult it →is to compare with perfect fairness, under such extremely complex relations, the standard of organisation of the imperfectly-known faunas of successive

periods

the

earth's

history.

We shall appreciate →OMIT this difficulty

the

....

more clearly, by looking to →OMIT certain existing faunas and floras. From the extraordinary manner in which European productions have recently spread over New Zealand, and have seized on places which must have been previously

occupied,

occupied

→by the indigenes, we must believe, that

that if

all the animals and plants of Great Britain were set free in New Zealand, →OMIT a multitude of British forms would →in the course of time become thoroughly

naturalized

naturalised

there, and would exterminate many of the natives. On the other hand, from →the fact that hardly a single inhabitant of the southern hemisphere

having

has

become wild in any part of Europe, we may →well doubt whether, if all the productions of New Zealand were set free in Great Britain,

whether

....

any considerable number would be enabled to seize on places now occupied by our native plants and animals. Under this point of view, the productions of Great Britain →stand much higher in the scale than those of New Zealand. Yet the