160 BULLETIN OF THE 
and are bordered by a fringe of sericite. The optical examination com- 
bined with chemical analysis led M. Renard to identify these plates 
finally as ilmenite. In another rock (Phyllite ottrelitifere de Mon- 
thermé) they occur with ottrelite. These metallic plates had been 
observed elsewhere by M. Renard and others, but their true nature not 
determined. : 
Minerals of the ottrelite family (‘ phyllite,” chloritoid, masonite, etc.) 
have been described from the rocks of New England by various miner- 
alogists, and by T. Sterry Hunt from the paleeozoic schists of Canada. 
The occurrence of this mineral in Maryland, in phyllite, has recently 
been mentioned by G. H. Williams.? 
In the complex of gneisses, schists, and massive crystalline rocks 
which cover the larger part of New England, there are certain areas of 
partially altered sediments, the paleozoic age of which has been estab- 
lished by fossils or stratigraphic considerations. One of the most im- 
portant of these is the strip forming the western edge of the Green 
Mountains, which has been proved by the labors of Dana, Wing, Wal- 
cott, and others to belong to the Cambrian and succeeding periods of 
the Palzeozoic. These ‘‘ Taconic rocks” consist of quartzites, crystal- 
line limestone, phyllites of various kinds, and fine-grained gneisses, with 
occasional conglomerates, especially near the base. That a large part 
of the more highly crystalline rocks to the eastward, in Massachu- 
setts at least, represent the same series still further metamorphosed, 
appears to definitely result from the work of the United States 
Geological Survey done under the direction of Professor Pumpelly, now 
going to press. 
Another important area of metamorphosed palzozoic sediments oc- 
curs in the eastern part of Rhode Island, on the shores of Narragan- 
sett Bay, extending northward into Southern Massachusetts; it is of 
Carboniferous age. The rocks are conglomerates, coal-beds, shales and 
schists of various kinds, which like the Cambrian rocks of the Green 
Mountains are intensely crumpled and metamorphosed. 
There are two well-known localities for ottrelite in or near this 
region: one that of the Masonite from Natic, R. 1, described by 
Jackson? in garnetiferous mica schist which occurred as glacial boulders, 
the other that of the ottrelite (Newportite) from the vicinity of New- 
port, R. I. Mr. T. N. Dale says of this occurrence, “ Boulders and 
pebbles of ottrelite schist abound about Newport, but I have failed to 
1 Johns Hopkins Univ. Circulars, September, 1889. 
2 Geology of Rhode Island, 1840, p. 47. 
Eo 
