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The Rise and Progress of Palaeontology
by Thomas Henry Huxley
That application of the sciences of biology and geology； which
is commonly known as palaeontology； took its origin in the mind
of the first person who； finding something like a shell； or a
bone； naturally imbedded in gravel or rock； indulged in
speculations upon the nature of this thing which he had dug out
this 〃fossil〃and upon the causes which had brought it into
such a position。 In this rudimentary form； a high antiquity may
safely be ascribed to palaeontology； inasmuch as we know that；
500 years before the Christian era； the philosophic doctrines of
Xenophanes were influenced by his observations upon the fossil
remains exposed in the quarries of Syracuse。 From this time
forth not only the philosophers； but the poets； the historians；
the geographers of antiquity occasionally refer to fossils；
and； after the revival of learning； lively controversies arose
respecting their real nature。 But hardly more than two centuries
have elapsed since this fundamental problem was first
exhaustively treated； it was only in the last century that the
archaeological value of fossilstheir importance； I mean； as
records of the history of the earthwas fully recognised；
the first adequate investigation of the fossil remains of any
large group of vertebrated animals is to be found in Cuvier's
〃Recherches sur les Ossemens Fossiles；〃 completed in 1822；
and； so modern is stratigraphical palaeontology； that its
founder； William Smith； lived to receive the just recognition of
his services by the award of the first Wollaston Medal in 1831。
But； although palaeontology is a comparatively youthful
scientific speciality； the mass of materials with which it has
to deal is already prodigious。 In the last fifty years the
number of known fossil remains of invertebrated animals has been
trebled or quadrupled。 The work of interpretation of vertebrate
fossils； the foundations of which were so solidly laid by
Cuvier； was carried on； with wonderful vigour and success； by
Agassiz in Switzerland； by Von Meyer in Germany； and last； but
not least； by Owen in this country； while； in later years； a
multitude of workers have laboured in the same field。 In many
groups of the animal kingdom the number of fossil forms already
known is as great as that of the existing species。 In some cases
it is much greater； and there are entire orders of animals of
the existence of which we should know nothing except for the
evidence afforded by fossil remains。 With all this it may be
safely assumed that； at the present moment； we are not
acquainted with a tittle of the fossils which will sooner or
later be discovered。 If we may judge by the profusion yielded
within the last few years by the Tertiary formations of North
America； there seems to be no limit to the multitude of
mammalian remains to be expected from that continent；
and analogy leads us to expect similar riches in Eastern Asia；
whenever the Tertiary formations of that region are as carefully
explored。 Again； we have； as yet； almost everything to learn
respecting the terrestrial population of the Mesozoic epoch；
and it seems as if the Western territories of the United States
were about to prove as instructive in regard to this point as
they have in respect of tertiary life。 My friend Professor Marsh
informs me that； within two years； remains of more than 160
distinct individuals of mammals； belonging to twenty species and
nine genera； have been found in a space not larger than the
floor of a good…sized room； while beds of the same age have
yielded 300 reptiles； varying in size from a length of 60 feet
or 80 feet to the dimensions of a rabbit。
The task which I have set myself to…night is to endeavour to lay
before you； as briefly as possible； a sketch of the successive
steps by which our present knowledge of the facts of
palaeontology and of those conclusions from them which are
indisputable； has been attained； and I beg leave to remind you；
at the outset； that in attempting to sketch the progress of a
branch of knowledge to which innumerable labours have
contributed； my business is rather with generalisations than
with details。 It is my object to mark the epochs of
palaeontology； not to recount all the events of its history。
That which I just now called the fundamental problem of
palaeontology； the question which has to be settled before any
other can be profitably discussed； is this； What is the nature
of fossils？ Are they； as the healthy common sense of the ancient
Greeks appears to have led them to assume without hesitation；
the remains of animals and plants？ Or are they； as was so
generally maintained in the fifteenth； sixteenth； and
seventeenth centuries； mere figured stones； portions of mineral
matter which have assumed the forms of leaves and shells and
bones； just as those portions of mineral matter which we call
crystals take on the form of regular geometrical solids？
Or； again； are they； as others thought； the products of the
germs of animals and of the seeds of plants which have lost
their way； as it were； in the bowels of the earth； and have
achieved only an imperfect and abortive development？ It is easy
to sneer at our ancestors for being disposed to reject the first
in favour of one or other of the last two hypotheses； but it is
much more profitable to try to discover why they； who were
really not one whit less sensible persons than our excellent
selves； should have been led to entertain views which strike us
as absurd； The belief in what is erroneously called spontaneous
generation； that is to say； in the development of living matter
out of mineral matter； apart from the agency of pre…existing
living matter； as an ordinary occurrence at the present day
which is still held by some of us； was universally accepted as
an obvious truth by them。 They could point to the arborescent
forms assumed by hoar…frost and by sundry metallic minerals as
evidence of the existence in nature of a 〃plastic force〃
competent to enable inorganic matter to assume the form of
organised bodies。 Then； as every one who is familiar with
fossils knows； they present innumerable gradations； from shells
and bones which exactly resemble the recent objects； to masses
of mere stone which； however accurately they repeat the outward
form of the organic body； have nothing else in common with it；
and； thence； to mere traces and faint impressions in the
continuous substance of the rock。 What we now know to be the
results of the chemical changes which take place in the course
of fossilisation； by which mineral is substituted for organic
substance； might； in the absence of such knowledge； be fairly
interpreted as the expression of a process of development in the
opposite directionfrom the mineral to the organic。 Moreover；
in an age when it would have seemed the most absurd of paradoxes
to suggest that the general level of the sea is constant； while
that of the solid land fluctuates up and down through thousands
of feet in a secular ground swell； it may well have appeared far
less hazardous to conceive that fossils are sports of nature
than to accept the necessary alternative； that all the inland
regions and highlands； in the rocks of which marine shells had
been found； had once been covered by the ocean。 It is not so
surprising； therefore； as it may at first seem； that although
such men as Leonardo da Vinci and Bernard Palissy took just
views of the nature of fossils； the opinion of the majority of
their contemporaries set strongly the other way； nor even that
error maintained itself long after the scientific grounds of the
true interpretation of fossils had been stated； in a manner that
left nothing to be desired； in the latter half of the
seventeenth century。 The person who rendered this good service
to palaeontology was Nicolas Steno； professor of anatomy in
Florence； though a Dane by birth。 Collectors of fossils at that
day were familiar with certain bodies termed 〃glossopetrae；〃 and
speculation was rife as to their nature。 In the first half of
the seventeenth century； Fabio Colonna had tried to convince his
colleagues of the famous Accademia dei Lincei that the
glossopetrae were merely fossil sharks' teeth； but his arguments
made no impression。 Fifty years later； Steno re…opened the
question； and； by dissecting the head of a shark and pointing
out the very exact correspondence of its teeth with the
glossopetrae； left no rational doubt as to the origin of the
latter。 Thus far； the work of Steno went little further than
that of Colonna； but it fortunately occurred to him to think out
the whole subject of the interpretation of fossils； and the
result of his meditations was the publication； in 1669； of a
little treatise with the very quaint title of 〃De Solido intra
Solidum naturaliter contento。〃 The general course of Steno's
argument may be stated in a