TRANSACTIONS OF SECTION C, 763 
the brothers Geikie; but the grand principles of physical geology have been so 
largely illustrated by the magnificent and simple features displayed on the other 
side of the Atlantic that we may well refer to our American brethren as leaders in 
this branch of study. The fourth branch, stratigraphical geology, is essentially 
British as regards origin, and, as everyone is aware, its scientific principles were 
established by William Smith, who was not only the father of English geology, 
but of stratigraphical geology in general. 
Few will deny that stratigraphical geology is the highest branch of the science, 
for, as has been well said, it ‘gathers up the sum of all that is made known by the 
other departments of the science, and makes it subservient to the interpretation of 
the geological history of the earth.’ The object of the stratigraphical geologist is 
to obtain information concerning all physical, climatic, and biological events which 
have occurred during each period of the past, and to arrange them in chronological 
order, so as to write a connected history of the earth. If all of this information 
were at our disposal, we could write a complete earth-history, and the task of the 
geologist would be ended. As it is, we have barely crossed the threshold of 
discovery, and the ‘imperfection of the geological record,’ like the ‘glorious un- 
certainty ’ of our national game, gives geology one of its great charms. Before 
passing on to consider more particularly the present state of the subject of our 
study, a few remarks upon this imperfection of the geological record may not be 
out of place, seeing that the term has been used by so many modern writers, and 
its exact signification occasionally misunderstood. The imperfection of the 
paleontological record is usually understood by the term when used, and it will be 
considered here as an illustration of the incompleteness of our knowledge of earth- 
history ; but it must be remembered that the imperfection of the physical record is 
equally striking, as will be insisted on more fully in the sequel. 
Specially prominent amongst the points upon which we are ignorant stands the 
nature of the Precambrian faunas. The extraordinary complexity of the earliest 
known Cambrian fauna has long been a matter for surprise, and the recent dis- 
coveries in connection with the Olened/us fauna do not diminish the feeling.? 
After commenting upon the varied nature of the earliest known fauna, the late 
Professor Huxley, in his Address to the Geological Society in 1862, stated that 
‘any admissible hypothesis of progressive moditication must be compatible with 
peeeience without progression, through indefinite periods. . . . Should such an 
ypothesis eventually be proved to be trus,.. . the conclusion will inevitably 
present itself, that the Palaeozoic, Mesozoic, and Cainozoic faune and flor, taken 
together, bear somewhat the same proportion to the whole series of living beings 
which have occupied this globe, as the existing fauna and flora do to them.’ 
Whether or not this estimate is correct, all geologists will agree that a vast period 
of time must have elapsed before the Cambrian period, and yet our ignorance of 
faunas existing prior to the time when the Olened/us fauna occupied the Cambrian 
seas is almost complete. True, many pre-Cambrian fossils have been described at 
various times, but, in the opinion of many competent judges, the organic nature of 
each. one of these requires confirmation. I need not, however, enlarge upon this 
matter, for 1 am glad to say we have amongst us a geologist who will at a later 
stage read a paper before this Section upon the subject of pre-Cambrian fossils, and 
there is no one better able, owing to his intimate acquaintance with the actual 
relics, to present fairly and impartially the arguments which have been advanced 
in favour of the organic origin of the objects which have been appealed to as 
evidences of organisms of pre-Cambrian age than our revered co-worker from 
Canada, Sir J. William Dawson. We may look forward with confidence to the 
future discovery of many faunas older than those of which we now possess certain 
1 Dr. C. D. Walcott, in his monograph on ‘The Fauna of the Lower Cambrian or 
Olenellus Zone ’ (Washington, 1890), records the following great groups as represented, 
in the Olenellus beds of America:—Spongie, Hydrozoa, Actinozoa, Echinodérmata, 
Annelida, ? (trails, burrows, and tracks), Brachiopoda, Lamellibranchiata, Gasteropoda, 
- Pteropoda, Crustacea, and Trilobita. Others are known as occurring in.beds of the 
same age in the Old World. i ee 
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