256 DR. THOMAS STERRY HUNT ON THE 
never rocks. These contorted strata, consisting of argillites, sandstones, conglomerates 
and limestones, were, during the next ten years, traced in Canada from Quebec north- 
eastward along the right bank of the lower St. Lawrence, and south-westward to the 
valley of Lake Champlain ; forming a belt from near Quebec southwards along the north- 
west base of the crystalline schists of the Green Mountain range. They were recognized 
by the Canadian survey as forming a part of the Graywacke-belt of Eaton, and in accord- 
ance with the view of Mather, and the earlier view of Emmons, were referred to the upper 
part of the Champlain division, and declared to embrace the so-called Hudson-River 
group, and the immediately succeeding strata ; including the representative of the Oneida, 
to which the sandstones of Sillery were supposed to belong. The organic remains as 
yet found in the belt, in Canada, were in limestone-pebbles in a conglomerate at Pointe 
Levis, which were erroneously supposed to be derived from the Trenton ; and certain forms 
ocourring in a limestone at Phillipsburgh, near Lake Champlain, also regarded as of Trenton 
sge. In 1855, were first described by James Hall, the graptolites of Pointe Levis, then 
spoken of by him as coming from “ near the summit of the Hudson-River group ;” to which 
horizon, considered as that of the Loraine shales, they were, on stratigraphical grounds, 
assigned by Logan. 
§ 104. As early as 1846, however, as we have seen, Emmons had, on stratigraphical 
grounds, assigned this Graywacke belt to the horizon of the Calciferous Sand-rock, and 
had declared it to contain certain peculiar forms of graptolites and of trilobites. This 
view, which was essentially a return to that of Eaton, was, however, combatted by all 
the other American geologists who had studied these rocks in Canada, and in Vermont ; 
C. B. Adams, W. B. Rogers and W. E. Logan uniting, on alleged structural grounds, to 
place these rocks at the summit of the Champlain division, or in the Second instead of 
the First Graywacke. 
§ 105. It was not until 1856 that the present writer discovered in association with the 
graptolitic beds of Pointe Levis, limestones containing a hitherto unobserved trilobitic 
fauna, the examination of which, by Billings, established the fact that the strata in question 
were older and not younger than the Trenton limestone; or in other words that they 
belonged to the First and not to the Second Graywacke. 
It was in 1861 that Logan, in a letter to Barrande, published this conclusion,then reached, 
and at the same time admitted the correctness of the later view of Emmons, for which this 
geologist had contended alone during fifteen years, namely,—that the belt of disturbed 
rocks which in Canada and in Vermont had been called the Hudson-River group, was 
in reality the stratigraphical equivalent of the lower members of the Champlain division, 
and older than the Trenton limestone. These strata were the Upper Taconic of Emmons, 
which he, in the same year, declared to be the equivalent of the rocks holding the first or 
primordial fauna of Barrande (§ 17). 
§ 106. The contact of these rocks near Quebec with the underlying gneiss is concealed 
by the horizontal Trenton limestone of the region. The green sandstone of Sillery here 
lies upon the other members of the Graywacke series, and since this had been regarded 
as the Oneida sandstone, overlying Loraine shales, the whole series was supposed to be in 
its natural order of succession. Hence it was, that while admitting the change of horizon 
ofthese rocks from above to below the Trenton limestone, the Sillery sandstone, as it was 
henceforth called, was placed at the summit, and the limestones and graptolitic slates of 
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