TACONIC QUESTION IN GEOLOGY. 247 
§ 81. The parallel belts of Lower Taconic rocks found east of the Blue Ridge in the 
southern states, and the final disappearance of these rocks beneath the tertiary, to the east 
of Raleigh, show that they were once widely spread over the floor of the more ancient crys- 
talline rocks which now form the Atlantic belt. To the north of New York, where this 
belt, greatly contracted between the James and the Hudson Rivers, again broadens, we 
might look for farther areas of Lower Taconic rocks in New England, and in the provinces 
lying farther to the north and east. We find in fact to the east of the Green Mountains, in 
Vermont, a series of limestones with soft micaceous slates, which have been compared with 
the Lower Taconic, and may perhaps represent it. To this horizon may also not impro- 
bably belong the considerable areas of argillites, often roofing-slates, found in the province 
of Quebee, to the north of Lake Memphremagog, extending to Melbourne, and occupying 
what I have called the Windsor basin. These argillites overlie the Huronian schists, and 
are themselves unconformably overlaid by Silurian limestones, which repose alike upon 
the argillites and upon the Huronian series. 
§ 82. Farther east, in Maine, are areas of argillites, and others of quartzose conglome- 
rates, limestones and soft talcose schists, which were declared by Emmons to resemble the 
Lower Taconic rocks of western Massachusetts, and to rest unconformably upon the 
ancient mica-schists and gneisses of the region. This series, which includes the limestones 
of Thomaston and of Camden, has, according to Emmons, a thickness, in the latter 
locality, of 2000 feet, and is by him regarded as belonging to the Lower Taconic; to which 
moreover, he refers, with much probability, many of the silicious and argillaceous schists 
of this part of Maine. The limestones and associated rocks of Cumberland, Rhode Island, 
are also supposed by Emmons to belong to the same horizon.* These, the present writer 
has not personally examined. 
§ 83. In southern New Brunswick, as I have pointed out, there are found numerous 
exposures of rocks closely resembling those of Camden. They have been much eroded, 
but are seen at several points along the coast, as at Frye’s Island, the peninsula of L’Etang, 
Pisarinco, and the mouth of the river St. John. At this last locality, a section along the 
Green-Head road, on the right bank of the river, is described in detail by Matthew and 
Bailey in the report of the geological survey of Canada for 1870. The strata, with a 
general southeast dip of about fifty degrees, have a breadth, across the strike, of 4100 feet, 
of which 1500 are limestones, and the remainder chiefly quartzites, often schistose, with 
argillaceous and somewhat micaceous schists, and occasional hornblendic layers. Con- 
siderable masses of conglomerate, with silicious and calcareous pebbles, are also included 
in the series, the members of which are not improbably repeated by dislocations. The 
limestones, of which there appear to be several masses two or three hundred feet in 
breadth, are in part, distinctly crystalline and white, or banded with blue and gray colors ; 
and in part, finely granular, greyish, schistose, and sometimes ~concretionary. They are 
frequently magnesian, and occasionally contain small masses of yellow serpentine, and a 
silvery-white mica. Portions of the limestone are apparently colored by a carbonaceous 
matter, and a bed of impure schistose graphite, which is wanting in the crystalline aspect 
of the Laurentian graphites, is mined in these rocks at the mouth of the river St. John. 
These limestones have yielded to Dr. J. W. Dawson the remains of Eozoon Canadense. 

* Emmons, Agriculture of New York, I., 97-101, and Amer. Geology, IT., 20-22; also, Hunt, Azoic Rocks, 179. 
