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Feb. 24, 1870 | 
NATURE 
437 
ON THE PROGRESS OF PALA ONTOLOGY 
ANNIVERSARY ADDRESS DELIVERED BEFORE THE 
GEOLOGICAL SOCIETY 
Ir is now eight years since, in the absence of the late Mr. 
Leonard Horner, who then presided over us, it fell to my lot, as 
one of the secretaries of this society, to draw up the customary 
Annual Address. I availed myself of the opportunity to endea- 
vour to ‘‘take stock” of that portion of the science of biology 
which is commonly called ‘‘ palzontology,” as it then existed ; 
and discussing one after another the doctrines held by palzon- 
tologists, I put before you the results of my attempts to sift the 
well-established from the hypothetical or the doubtful. Permit 
me briefly to recall to your minds what those results were. » 
1. The living population of all parts of the earth’s surface 
which have yet been examined, has undergone a succession of 
changes which, upon the whole, have been of a slow and gradual 
character. 
2. When the fossil remains which are the evidences of these 
successive changes, as they have occurred in any two more or less 
distant parts of the surface of the earth, are compared, they 
exhibit a certain broad and general parallelism. In other 
words, certain forms of life in one locality occur in the same 
general order of succession as, or are homotaxial with, similar 
forms in the other locality. 
3. Homotaxis is not to be held identical with synchronism 
without independent evidence. It is possible that similar, or 
even identical, faunze and floree in two different localities may be 
of extremely different ages, if the term ‘‘ age ”is used in its proper 
chronological sense. I stated that ‘‘ geographical provinces or 
zones may have been as distinctly marked in the Paleozic epoch 
as at present ; and those seemingly sudden appearances of new 
genera and species, which we ascribe to new creation, may be 
simple results of migration.” 
4. The opinion that the oldest known fossils are the earliest 
forms of life, has no solid foundation. 
5. If we confine ourselves to positively ascertained facts, the 
total amount of change in the forms of animal and vegetable life 
since the existence of such forms is recorded, is small. When 
compared with the lapse of time since the first appearance of 
these forms, the amount of change is wonderfully small. More- 
over, in each great group of the animal and vegetable kingdoms, 
there are certain forms which I termed PERSISTENT TYPEs, 
which have remained, with but very little apparent change, from 
their first appearance to the present time. 
7. In answer to the question ‘‘ What then does an impartial 
survey of the positively ascertained truths of paleontology testify, 
in relation to the common doctrines of progressive modification, 
which suppose that modification to have taken place by a neces- 
sary progress from more to less embryonic forms, from more to 
less generalised types, within the limits of the period repre- 
sented by the fossiliferous rocks ?’’ I reply, “It negatives these 
doctrines, for it either shows us no evidence of such modification, 
or demonstrates such modification as has occurred to have been 
very slight ; and, as to the nature of that modification, it yields no 
evidence whatsoever that the earlier members of any long con- 
tinued group were more generalised in structure than the later 
ones.” 
I think I cannot employ my last opportunity of addressing you, 
officially, more properly—I may say more dutifully—than in re- 
vising these old judgments with such help as further knowledge 
and reflection, and an extreme desire to get at the truth, may 
afford me. 
1. With respect to the first proposition, I may remark that 
whatever may be the case among physical] geologists, catastrophic 
paleontologists are practically extinct. It is now no part of re- 
cognised geological doctrine that the species of one formation all 
died out and were replaced by a bran-new set in the next forma- 
tion. On the contrary, it is generally, if not universally, 
agreed that the succession of life has been the result of a slow and 
gradual replacement of species by species; and that all appear- 
ances of abruptness of change are due to breaks in the series of 
deposits, or other changes in physical conditions. The continuity 
of living forms has been unbroken from the earliest times to 
the present day. 
2, 3. The use of the word ‘‘homotaxis” instead of ‘‘syn- 
chronism”’ has not, so far as I know, found much favour in the 
eyes of geologists. I hope, therefore, that it is a love for scien- 
tific caution, and not mere personal affection for a bantling of 
my own, which leads me still to think that the change of phrase 
? 
is of importance; and, that the sooner it is made, the sooner shall 
we get rid of a number of pitfalls which beset the reasoner upon 
the facts and theories of geology. 
One of the latest pieces of foreign intelligence which has 
reached us is the information that the Austrian geologists have, 
at last, succumbed to the weighty evidence which M. Barrande has 
accumulated, and have admitted the doctrine of colonies. But 
the admission of the doctrine of colonies implies the further ad- 
mission that even identity of organic remains is no proof of the 
synchronism of the deposits which contain them. 
4. The discussions touching the Zozcox which commenced in 
1864, have abundantly justified the fourth proposition. In 1862, 
the oldest record of life was in the Cambrian Rocks; but if the 
£o0z00n be, as Principal Dawson and Dr. Carpenter have shown so 
much reason for believing, the remains of a living being, the dis- 
covery of its true nature carried life back to a period which, as 
Sir William Logan has observed, is as remote from that during 
which the Cambrian Rocks were deposited, as the Cambrian 
epoch itself is from the tertiaries. In other words, the ascer- 
tained duration of life upon the globe was nearly doubled, at a 
stroke. 
5. The significance of persistent types, and of the small amount 
of change which has taken place éven in those forms which can 
be shown to have been modified, becomes greater and greater in 
my eyes, the longer I occupy myself with the biology of the 
past. 
Consider how long a time has elapsed since the Miocene 
epoch. Yet, at that time, there is reason to believe that every 
important group in every order of the JZammalia was repre- 
sented. | Even the comparatively scanty Eocene fauna yields 
examples of the orders Cheiroptera, [nsectivora, Rodentia, and Pe- 
rissodactyla ; of Artiodactyla under both the Ruminant and 
the Porcine modifications; of Carnivora, Cetacea, and Marsu- 
pialia. 
Or, if we go back to the older half of the Mesozoic epoch, 
how truly surprising it is to find every order of the Refti/ia, 
except the Ofhzdia, represented ; while some groups, such as 
the Ornzthoscelida and the Pterosauria, more specialised than any 
which now exist, abounded. 
There is one division of the Amphibia which offers especially 
important evidence upon this point, inasmuch as it bridges over 
the gap between the Mesozoic and the Paleozoic formations, often 
supposed to be of such prodigious magnitude, extending, as it 
does, from the bottom of the Carboniferous series to the top of the 
Trias, if not into the Lias. I refer to the Labyrinthodonts. As 
the address of 1862 was passing through the press, I was able to 
mention, in a note, the discovery of a large Labyrinthodont, with 
well-ossified vertebree, from the Edinburgh coal-field. Since 
that time eight or ten distinct genera of Labyrinthodonts have 
been discovered in the carboniferous rocks of England, Scotland, 
and Ireland, not to mention the American forms described by 
Principal Dawson and Professor Cope. So that, at the present 
time, the Labyrinthodont Fauna of the Carboniferous rocks is 
more extensive and diversified than that of the Trias, while its 
chief types, so far as osteology enables us to judge, are quite as 
highly organised. Thus it is certain tha ta comparatively highly 
organised vertebrate type, such as that of the Labyrinthodonts, 
is capable of persisting, with no considerable change, through 
the period represented by the vast deposits which constitute the 
Carboniferous, the Permian, and the Triassic formations. 
The very remarkable results which have been brought to light 
by the sounding and dredging operations, which have been carried 
on with such remarkable success by the expeditions sent out by our 
own, the American, and the Swedish Governments, under the 
supervision of able naturalists, havea bearing in the same direction. 
These investigations have demonstrated the existence, at great 
depths in the ocean, of living animals in some cases identical 
with, in others very similar to, those which are found fossilised 
in the white chalk. The Globigerine, Coccoliths, Coccospheres, 
Discoliths, in the one are absolutely identical with those in the 
other ; there are identical, or closely analogous, species of Sponges, 
Echinoderms, and Brachiopods. Off the coast of Portugal, there 
now lives a species of Beryx, which, doubtless, leaves its bones 
and scales here and there in the Atlantic ooze, as its predecessor 
left its spoils in the mud of the sea of the Cretaceous epoch. 
Many years ago* I ventured to speak of the Atlantic mud as 
“modern chalk,” and I know of no fact inconsistent with the 
view which Professor Wyville Thomson has advocated, that the * 
modern chalk is not only the lineal descendant of the ancient 
© Saturday Review, 1858, ‘ Chalk, Ancient and Modern.” 
