112 THE HAWKESBURY SANDSTONE. 
may have been fresh-water, it is objected. But the fo 
fresh-water fossils. The ferns are land ferns. 7h 
land fern, so is Gleichenia, and so are all the ferns 
The few water ferns that are known in existence are s0 
that a very little experience would distinguish them. | 
none of these in the sandstone. We ought also to have 
shells or other fresh-water remains, but we find none 
species of fish, which are rarely found in what I readily 
may have been lagoons or creeks in this formation. Thenag 
the sandstones and shales and the joints traversite 
this Mr. Wilkinson overlooks the fact that I admittet 
and 519 fissures to have been caused i inti 
am sure he forgets how this oxidation is explained | 
_ His words, “oxidation of water containing iron in 
