Bane of the Taconlc or Lotrer C<i mhrlan. — W/itrfiell. 238 
of a non-conformity at its summit. That part wliieh first 
succeeds this plane is strongly paradoxidean, while the upper- 
most portion is broadly equivalent, paleontologically, to the 
Olenus horizon of Britain, or to the lower part of the St. 
Croix series of the upper ^Mississippi valle}-. In the whole 
series in New Brunswick no species of Olenelhis is reported 
by Matthew, who is ratlier inclined to believe its position is 
held by the species of Paradoxides and other trilobites found 
in his "Division 1." It is possible, however, and perhaps 
probable that the horizon for Olenelhis is to be sought for in 
the Etcheminian, and that the trace of non-conformity at the 
top of that group indicates, as in Europe, the cause of the 
change from Olenellus to Paradoxides, viz., volcanic disturb- 
ance. Whether Olenellus ever existed in New Brunswick or 
not, it is plain that a great sei'ies of clastic strata, nearly non- 
fossiliferous, there extends downward below the lowest trilo- 
bitic fossils, and that the whole has been included by Matthew 
in the Lower Cambrian. The thickness of this lowest part is 
1,200 feet. 
The Cambrian of Wales is the Taconic of America, even in 
the errors at first committed by the respective authors of 
these terms. The Taconic, however, has never been limited 
at the bottom except at the great plane of non-conformity 
which, as Sir Archibald Giekie shows, extends through the 
northern parts of Europe and North America, and which sud- 
denly separates the crystalline Archean from the nearly hori- 
zontal elastics which lie upon it with "violent" non-conformit3^ 
As the histories of these formations are developed in geolog- 
ical literature they are showMi to have a wonderful similarity. 
This is true not only as to the nature of the rocks of which 
they are composed, the fossils which they contain and the 
succession of events which make up the epochs of time repre- 
sented, but in the progress of the investigations which have 
been carried on on opposite sides of the Atlantic. But the 
Taconic, from the first, has extended down to the "sedimentary 
base" which coincides with this great plane of non-conform- 
ity. It embraces, therefore, all the eruptive rocks which have 
their dates within Taconic time, whether they be ash-bed frag- 
mentals or injected or eruptive traps. If it be in general the 
