remarks;
and to show how liable we are to error in supposing that whole groups of species have suddenly been produced. Even in so short an interval as that between the first and second editions of Pictet's
great work on Palæontology, published in 1844-46 and in
1853-57, the conclusions on the first appearance and disappearance of several groups of animals have been considerably modified; and a third edition would require still further changes. I may recall the well-known fact that in geological treatises, published not many years ago,
mammals were mammals were 1869 1872 |
the great class of mammals was 1859 1860 |
the whole class of mammals was 1861 1866 |
always spoken of as having abruptly come in at the commencement of the tertiary series. And now one of the richest known accumulations of fossil
mammals mammals 1859 1872 | mammals, 1860 1861 1866 1869 |
belongs belongs 1859 1872 |
for its thickness, belongs 1860 1861 1866 1869 |
to the middle of the secondary series; and
....... 1866 1869 1872 | one 1859 1860 1861 |
true
mammals mammals 1866 1869 1872 | mammal 1859 1860 1861 |
have have 1866 1869 1872 | has 1859 1860 1861 |
been discovered in the new red sandstone at nearly the commencement of this great series. Cuvier used to urge that no monkey occurred in any tertiary stratum; but now extinct species have been discovered in India, South America, and in
Europe, Europe, 1869 1872 | Europe 1859 1860 1861 |
....... 1869 1872 | even 1859 1860 1861 |
as far back as the
miocene miocene 1869 1872 | eocene 1859 1860 1861 |
stage. Had it not been for the rare accident of the preservation of footsteps in the new red sandstone of the United States, who would have ventured to suppose
that that 1872 | that, 1860 1861 1866 1869 |
....... 1872 | besides reptiles, 1860 1861 1866 1869 |
no less than at least thirty
different bird-like animals, different bird-like animals, 1872 |
kinds of birds, 1860 1861 1866 1869 |
some of gigantic size, existed during that period? ↑1 blocks not present in 1859 1860 1872; present in 1861 1866 1869 | Notwithstanding that the number of joints shown in the fossil impressions correspond
with the number in the several toes of living birds' feet, some authors doubt whether the animals which left the
impressions were really birds.
|
Not a fragment of bone has been discovered in these
beds. beds. 1861 1866 1869 1872 |
beds. Notwithstanding that the number of joints shown in the fossil impressions correspond with the number in the several toes of living birds feet, some authors doubt whether the animals which left the impressions were really birds. 1860 |
Not long ago, palæontologists maintained that the whole class of birds came suddenly into existence during the eocene period; but now we know, on the authority of Professor Owen, that a bird certainly lived during the deposition of the upper greensand; and still more recently, that strange bird, the Archeopteryx, with a long lizard-like tail, bearing a pair of feathers on each joint, and with its wings furnished with two free claws, has been discovered in the oolitic slates of Solenhofen. Hardly any recent discovery shows more forcibly than this, how little we as yet know of the former inhabitants of the world. ↑1 blocks not present in 1859 1872; present in 1860 1861 1866 1869 | Until quite recently these authors might have maintained, and some have maintained, that the whole class of birds came suddenly into existence during an early tertiary
period; but now we know, on the authority of Professor Owen
(as may be seen in Lyells Manual),
that a bird certainly lived during the deposition of the upper greensand. |
|
I may give another instance,
which, which, 1861 1866 1869 1872 | which 1859 1860 |
from having passed under my own
eyes, eyes, 1861 1866 1869 1872 | eyes 1859 1860 |
has much struck me. In a memoir on Fossil Sessile Cirripedes, I
....... 1872 | have 1859 1860 1861 1866 1869 |
stated that, from the
|