1895.] The First Fauna of the Earth. 979 
THE FIRST FAUNA OF THE EARTH. 
By Josern F. JAMES. 
(Continued from page 887). 
In 1886, there came an announcement from Sweden that 
was received with incredulity upon this side of the Atlantic. 
The geologists there had determined that instead of the 
Olenellus fauna occupying the middle position, it was at the 
base, and the Paradoxides fauna was in the middle. Continu- 
ous sections showed the rocks of Lower, Middle and Upper 
Cambrian age in conformable succession, and the question at 
once arose, Could there he one sequence upon the eastern and 
a different one on the western side of the Atlantic? If not, 
then which was correct? The difficulty on this side was to 
find a continuous section, and it was not until 1888 that it was 
found. In that year, Mr. C. D. Walcott, now the Director of 
the U. S. Geological Survey, found in Newfoundland the de- 
sired section. Here the Olenellus fauna was at the base, and 
the Paradoxides fauna was above it. 
The base of the Cambrian being thus at last defined, it then 
remained to ascertain the extent and variety of organic life in 
these old rocks. To Mr. Walcott again the world owes the 
best exposition of this fauna. In a paper published in 1890, 
he showed there was a variety and profusion of life that had 
never before been imagined. In this fauna there were repre- 
sentatives of all the great classes of invertebrates. Strange to 
say, the most highly organized class had the greatest number 
of species, as shown below: 
Spongie . : : . 4 species. 
Hydrozoa . ‘ : ; 2 species. 
Actinozoa : : : è . 9 species. 
Echinodermata . ; : : 1 species. 
Annelida (?) . 3 ; ; i . 6 species. 
Brachiopoda : ; : ; ; 29 species. 
Lamellibranchiata . ; : . 8 species. 
