30 
Bulletm of Natural History Society. 
been had, than that obtained by the circulation among the- 
American geologists, by Dr. Fraser, as reporter on the Archsean 
rocks, to the International Congress of Geologists, of the 
question, “7s Eozoon Canadense of organic origin’^? The 
replies to this question will be found in the September num- 
ber (1888) of the “ American Geologist,” p. 175, where we find, 
that among fourteen geologists consulted, if we leave out the 
two original investigators of Eozoon, Sir Wm. Dawson and. 
Dr. Hunt, only one, on his own authority, pronounced Eozoon 
to be organic. This geologist is Mr. C. D. Walcott, of the 
United States Geological Survey. But probably a number of 
the others have not had the opportunity of studying Eozoon 
in the field. 
The mode of occurrence of Eozoon in the rocks in which 
it is found is such that one accustomed to observe the 
older organisms, resembling the reef-corals, can hardly come 
to any other conclusion than that Eozoon is of organic origin, 
and this irrespective of the evidence supplied by the micro- 
scope. 
The outward appearance of Eozoon is so much like that of 
some stromatoporoid corals that if the object were found in 
Ordovician or Silurian rocks its organic nature would scarcely 
be questioned. 
Admitting that Eozoon is of organic origin, it certainly is 
a remarkable fact that it is the only organism of its kind 
known; and still more remarkable that it stands almost alone 
as a solitary animal structure in the great system of rocks to 
which it pertains. 
Remains of other animals have been sought for in these 
Eozoic rocks, but so far as I know without much success. 
Discoveries of pre-palaeozoic fossils have from time to time 
been reported but many of these have afterwards been found 
to pertain to the Cambrian or Ordovician faunas, or are so 
obscure and indefinite that they are of little value in carrying 
back the history of life behind the Cambrian forms. 
Often also the absence of a definite Cambrian horizon leaves 
the exact age of such reputed pre-Cambrian animals open ta 
doubt. Such for a long time was the position of the Olenellus- 
