Some Points in Geology. 3 
having built them up by reef-like masses; and their graphite may 
have been coal, and their iron-ore and phosphates were probably 
formed, as now, in association with organic matter. This great 
‘Laurentian’ gneiss of Canada, Norway, and elsewhere, the oldest rock 
found by geologists stepping down from bed to bed, stage to stage, 
from one rock-system to another, from the present to the past, is 
sometimes almost a granite, sometimes almost a syenite, but still 
presents itself as a crumpled altered bedded rock, made of the old 
detritus of unknown shores, and associated with limestones of organic 
origin, just as sands, muds, shell-beds, and microzoal ooze are now 
formed in shallows and the deep. And if the Eozoan shell-crust, 
with its infilling of silicates, alone presents itself as witness of that 
unknown sea, are we to suppose that there were no other species 
then? Have we got back to the first of earth’s created beings? It 
is lowly and simple as an organism; the name of its natural order 
says as much—it is a Proto-zodn: ought it not to have been verily 
the first? That is not for us to say. ‘There are two things to be 
remembered—lst. It owes its preservation to the silicates of mag- 
nesia, alumina, &c. having filled its tubes and chambers in that old 
sea, just as a silicate of iron, alumina, &c. fills similar shells in the 
sea to-day; the water yielding different salts at different periods. 
2ndly. These similar shells (Foraminifera) of the present and the 
past live at great depths, covering the sea-bed there, and heaping 
lime and silicates that can be preserved alone when the ocean-floor 
has been upraised, with its gradually augmented coatings, and 
fashioned as dry land. Judging by analogy, then, the Eozoan rock of 
Canada was the foraminiferal formation in one part of an ocean 
which elsewhere may have borne manifold and higher species, and 
buried them in sands and muds, that have since lost all form and 
feature by the metamorphism of age and pressure, or which were 
altogether shorn away by wave and weather when the old ocean-bed 
was lifted up. 
Eozoén Canadense, with its free growth, cell by cell, over the 
large area of a square foot, and tier above tier for five or six inches, 
far exceeds even the wildest and most zoophytic or sponge-like 
of its existing representatives; and in this light we might think 
of it as amore repetitive and less specialized form; but it stands 
higher than the free-growing forms that we know, for it has a shell- 
structure of as delicate and high an organization as the highest 
Foraminifer—Nummulina. To that species it may be said to supply 
a free-growing form or condition, such as other species have; but, 
that this old Laurentian creature was essentially lower in the scale of 
being than its young Nummuline brother, is not the opinion of Dr. 
Carpenter, who has thought over it with the results of Dr. Dawson’s 
and his own examination of the fossil before him. 
A friend informs me that his microscope shows Eozoan structure 
in some of the green and white marble of Connemara. There then 
Laurentian rocks may be looked for. Sir Roderick Murchison 
demonstrated their existence in NW. Britain; Dr. Holl has boldly 
- argued that a Laurentian heart holds up the Malvern range; Mr. 
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