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, 1860 1861 1866 1869 | that 1872 |
besides reptiles, besides reptiles, 1860 1861 1866 1869 | besides reptiles, 1872 |
no less than at least thirty
kinds of birds, kinds of birds, 1860 1861 1866 1869 |
different bird-like animals, 1872 |
some of gigantic size, existed during that period? 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.
↑2 blocks not present in 1859 1860 1861 1866 1869; present in 1872 | 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.
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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.
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. ↑2 blocks not present in 1860 1861 1866 1869 1872; present in 1859 | The most striking case, however, is that of the Whale family; as these animals have huge bones, are marine, and range over the world, the fact of not a single bone of a whale having been discovered in any secondary formation, seemed fully to justify the belief that this great and distinct order had been suddenly produced in the interval between the latest secondary and earliest tertiary formation.
But now we may read in the Supplement to Lyell's 'Manual,' published in 1858, clear evidence of the existence of whales in the upper greensand, some time before the close of the secondary period.
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I may give another instance, which
from having passed under my own eyes
has much struck me. In a memoir on Fossil Sessile Cirripedes, I
have have 1859 1860 1861 1866 1869 | have 1872 |
stated that, from the
number number 1859 1860 1861 1866 | large number 1869 1872 |
of existing and extinct tertiary species; from the extraordinary abundance of the individuals of many species all over the world, from the Arctic regions to the equator, inhabiting various zones of depths from the upper tidal limits to 50 fathoms; from the perfect manner in which specimens are
pre- served pre- served 1866 | preserved 1859 1860 1861 1869 1872 |
in the oldest tertiary beds; from the ease with which even a fragment of a valve can be recognised; from all these circumstances, I inferred that
had sessile cirripedes existed during the secondary periods, they would certainly have been preserved and discovered; and as not one species had been
discovered in beds of this age, I concluded that this great group had been suddenly developed at the commencement of the tertiary series. This was a sore trouble to me, adding as I
thought thought 1859 1860 1861 1866 1869 | then thought 1872 |
one more instance of the abrupt appearance of a great group of species. But my work had hardly been published, when a skilful palæontologist, M. Bosquet, sent me a drawing of a perfect specimen of an unmistakeable sessile cirripede, which he had himself extracted from the chalk of Belgium. And, as if to make the case as striking as possible, this
sessile sessile 1859 1860 1861 1866 1869 | sessile 1872 |
cirripede was a Chthamalus, a very common, large, and ubiquitous genus, of which not one
specimen specimen 1859 1860 1861 1866 1869 | species 1872 |
has as yet been found even in any tertiary stratum. |