Origin of Species Variorum

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

Thus in the Galapagos Islands nearly every land-bird, but only two out of the eleven marine birds, are peculiar; and it is obvious that marine birds could arrive at these islands more easily than land-birds.

→ a single endemic land-bird; 1869 1872

one endemic land bird; 1859

one endemic land-bird; 1860 1861 1866

→ occasionally or even frequently visit 1869 1872

during their great annual migrations, visit either periodically or occasionally 1859 1860 1861

occasionally visit 1866

→ from the neighbouring continents with 1869 1872

by 1859 1860 1861 1866

→ struggled together, and 1869

struggled together in their former homes, and have 1859 1860 1861 1866

there struggled together, and have 1872

→ adapted; hence when settled in their new homes, each kind would be kept by the others to its proper place and habits, and would consequently be but little liable to modification. 1869

adapted to each other; and when settled in their new homes, each kind will have been kept by the others to their proper places and habits, and will consequently have been little liable to modification. 1859 1860 1861

adapted to each other; and when settled in their new homes, each kind will have been kept by the others to its proper place and habits, and will consequently have been little liable to modification. 1866

co-adapted. 1872

→ from 1860 1861 1866 1869

often arriving from 1872

→ across three or four hundred miles of open sea far more easily than land-shells. 1869 1872

far more easily than land-shells, across three or four hundred miles of open sea. 1859 1861 1866

far more easily than land- shells, across three or four hundred miles of open sea. 1860

→ nearly similar cases. 1869

analogous facts. 1859 1860 1861 1866

nearly parallel cases. 1872

→ animals of certain whole 1866 1869 1872

certain 1859 1860 1861

→ other classes: thus 1869

the other inhabitants; 1859 1860 1861

animals belonging to other classes; thus 1866

other classes; thus 1872

than land-birds. ↑ Bermuda, on the other hand, which lies at about the same distance from North America as the Galapagos Islands do from South America, and which has a very peculiar soil, does not possess →a single endemic land-bird; and we know from Mr. J. M.

Jones's

Joness

admirable account of Bermuda, that very many North American

birds,

birds

→occasionally or even frequently visit this island. Almost every year, as I am informed by Mr. E. V. Harcourt, many European and African birds are blown to Madeira; this island is inhabited by 99 kinds, of which one alone is peculiar, though very closely related to a European form; and three or four other species are confined to this island and to the Canaries. So that

these two

the two

the

Islands

islands

of Bermuda and Madeira have been stocked →from the neighbouring continents with birds, which for long ages have →struggled together, and become mutually →adapted; hence when settled in their new homes, each kind would be kept by the others to its proper place and habits, and would consequently be but little liable to modification. Any tendency to modification

will,

will

would

also,

also

have been

checked by intercrossing with the unmodified

immigrants,

immigrants

→from the mother-country.

Madeira,

Madeira

again,

again

is inhabited by a wonderful number of peculiar land-shells, whereas not one species of sea-shell is

confined

peculiar

to its

shores;

shores:

now, though we do not know how sea-shells are dispersed, yet we can see that their eggs or larvæ, perhaps attached to

sea-weed

seaweed

or floating timber, or to the feet of wading-birds, might be transported →across three or four hundred miles of open sea far more easily than land-shells. The different orders of insects

inhabiting

Madeira

apparently

....

present →nearly similar cases.

Oceanic islands are sometimes deficient in →animals of certain whole classes, and their places are

apparently

....

occupied by →other classes: thus