TACONIC QUESTION IN GEOLOGY. 241 
§ 64. Prof. Kerr, while recognizing in these rocks the strata described by Emmons 
under the name of Taconic, gave them, as he tells us, in his report of 1875, provisionally, 
the name of Huronian ; both designations appearing in the legend of the accompanying 
map. In explanation of this, it is tobe remarked that he then included all of the more 
ancient crystalline rocks of North Carolina under the head of Laurentian, whlch he divided 
into Lower Laurentian (also called granite in his engraved sections) and Upper Laurentian. 
The latter name, at one time used by the geological survey of Canada to designate an 
entirely different group of rocks, the Norian, was by Prof. Kerr applied to the series 
of younger gneisses and micaceous and hornblendic schists, (with included beds of chrysolite - 
or olivine-rock,) which is the Montalban series of the author. 
These rocks I found, in 1877, to rest in Mitchell county, North Carolina, directly upon 
the ancient granitoid gneisses of the Laurenrian, the Huronian being absent. The true 
place of this, as appears from multiplied observations, is below, not above the Montalban, 
and it, moreover, differs entirely in its lithological characters from the Lower Taconic rocks, 
which are found above the Montalban horizon. It remains, however, to be determined 
whether true Huronian and Arvonian rocks may not occur in parts of North Carolina, and 
may not be represented by some of the greenstones and feldspar-porphyries, noticed by Prof. 
Kerr as found in parts of the Montalban (Upper Laurentian) area of the state. 
§ 65. The Taconic strata of North Carolina are described by Kerr as resting in some 
places upon the the granitic rocks, and in others upon the upper or Montalban series, 
and in part made up of its ruins. Pebbles of the older crystalline rocks, in which Ihave 
recognized both gneiss and mica-schist, are often met with in the conglomerates of the 
series. In the quartzites of the second belt at Troy, in Montgomery County, occur the sili- 
cious concretions regarded by Emmons as organic, and described by him under the name of 
Paleotrochis. Other beds of granular quartzite are flexible, constituting the variety 
known as itacolumite. With these, besides the usual argillites and unctuous schists, are 
found beds of pure massive pyrophyllite, which was by Emmons described as agalmatolite, 
and has been mistaken for steatite or compact talc, beds of which are also met within 
this series. The schists are sometimes graphitic, and even include beds of graphite, as in 
the King’s-Mountain belt. The quartzites of the series frequently contain kyanite and 
rutile, and also include, as in Pennsylvania, both magnetic and specular iron-ores, as will be 
noticed farther on in the account of these rocks in South Carolina. The characteristic lime- 
stones, often becoming marbles, and the limonites of epigenic origin here, as in other 
regions, mark the series. 
§ 66. I have elsewhere described these rocks as seen by me in the fourth belt in North 
Carolina, on the north branch of Catawba, near Marion, in McDowell county, where they 
were first seen by Maclure; and have noticed the granular quartz-rock, often becoming 
thinly bedded and flexible, the unctuous micaceous schists, the limonites, and the 
limestones, as having all the characters of these rocks as seen in Pennsylvania*. 
A section in this same belt farther southwest, at Warm Springs, in Buncombe 
county, described by Emmons in 1855, may be compared with similar sections of the same 
rocks in the Appalachian valley in Virginia, in Pennsylvania, in Berkshire county and 
Massachusetts; with which latter he especially compared it. The Taconic rocks, with 

Proc. Boston Soc. Nat. Hist., 1878, xix., p. 277, and Azoic Rocks, pp. 207, 208. 
Sec. IV., 1883. 31. 
