266 The American Geologist. May, 1902. 
and in the hills north of Chilcoot pass on the road from Sil- 
ver Peak to South Klondyke, there are dark thin bedded cherts 
with Jayers of gray graptolite slates, and smaller amounts 
of reddish slates, and an occasional limestone layer. The most 
abundant and characteristic fossils of this formation, are the 
graptolites found :n the gray slates. 
The collection of graptolites was examined by Mr. Chas. 
Schuchert who states that there are two horizons represented, 
one, the Normanskill or Lower Trentonian, and the other the - 
Quebec horizon. Nearly all of the graptolites, howeyer, belong 
to the Normanskill zone. In the Quebec horizon, Mr. Schu- 
chert found two characteristic genera, Didymograptus and Tet- 
ragraptus. 
In the Palmetto mountains and at some other points there 
are very numerous streaks of light colored felsitic rocks, in- 
terbedded with the dark cherts of the Normanskill zone. In 
certain cases similar looking streaks are metamorphosed into 
garnet rocks. “fhe microscope shows that these felsitic layers 
represent altered ihyolitic or dacitic tuffs and lavas, but the 
nature of the lavers which have given rise to garnet rocks, 
is not yet clear, for it is evident that acid rocks, having the 
composition of rhyolytes and dacytes, could not be altered into 
garnet rocks without an addition of a large amount of lime. 
These interbedded lavas afford certain evidence that in Ordo- 
vician time there were volcanic eruptions in the region. 
Carboniferous. South-east of Candelaria by the Columbus 
trail are sandstones and slate with cherty layers. No study was 
made of the formation. Tossils were collected at a point about 
3 niles north-west cf Columbus, at an elevation of about 4,- 
oco feet. The fossils were first found by William Grozenger 
of Columbus. ‘lhey are in part spirifers, and are referred by 
Mr. Chas. Schuchert to the Carboniferous period. 
Mr. Schuchert writes—‘Both forms are specifically unde- 
termined at present. The spirifer (apparently a new species) 
belongs to the S. cameratus section, fossils recognized as char- 
acteristic of the Upper Carbonic. The Productus is appar- 
ently identical with one from the region north of Mt. Shasta 
in California, also associated with Upper Carbonic species. 
These forms remind one more of the fauna found in the Shasta 
region than the fauna of a similar age farther cast.” 
