220 The American Geologist. October, 1904. 
the rare places where the gneiss comes up from beneath its cover. The 
zone reaches the west coast in the stretch in which He the cities Sakata 
and Akita. To the Kitakami zone on the other hand we must refer 
everything which lies in the extension of its strike direction and to the 
eastward of the Abukuma zone. We are thus led at once over the Kit- 
akami river. There appears still a small gneiss dome. in the high Sen- 
nin-take (948 m.), which may form the boundary of the gneiss zone; 
but with this exception are found in the extension through all of Mutsu 
and beyond toward western Yezo only such formations as are referred 
to the Paleozoic group. 
Thus the Hidaka range (upon Yezo), Kitakami, and x^bukuma ap- 
pear as three parallel zones of the core folded in post-Carboniferous 
time and striking between N by W and NNW. Their mutual connection 
cannot yet be made out. There are not lacking evidences of a separ- 
ation through strike faults ; for the above drawn profile of Abukuma 
indicates that Kitakami is sunk away upon its east side, and likewise 
at the Hidaka range the. steep and short eastern descent in contrast to 
the gentle western slope is marked. But there enter also abnormal 
phenomena. For the strike of the Paleozoic sediments is in Mutsu 
(the northeastern part of Hondo) ENE, in western Yezo it is for the 
most part NE, but also in part E 10° N. 
The investigations up to the present appear to give no satisfactory 
answer to the question where the southern continuation of the three 
zones lies. Hidaka strikes out toward the sea and breaks off; for Ki- 
takami the same holds true according to Jimbo's already mentioned 
representation. For Abukuma it is assumed that a turning back occurs 
toward the Kwanto range, where the WNW direction controls every- 
thing, and that the broad alluvial bay of Tokyo conceals the intermed- 
iate members. For a conclusion the following facts may be introduced : 
(i) In the Abukuma mountain region it holds, so far as may be learn- 
ed from the accessible writings, that the strike direction SSE to S by E. 
is the dominant one even to the southernmost part ; (2) The Kwanto 
range does not consist of the Archaean gneisses of Abukuma but of 
Paleozoic sediments, and where on the northeast side a band of older 
phyllite occurs it is referred to the Algonkian Sambagawa beds; (3) 
In the extension of the Abukuma range to the S by E lie at the mouth 
of the Tonegawa the small hills of Tschocshi made firm land through 
its alluvial and coast deposits. Here occur Paleozoic sediments with 
SSE strike and one might see in them a last outlier of a member of the 
Abukuma zone; (4) On the other hand there arises to the west from 
southern Abukuma the N-S directed Yamiso-tsukuba hill country as- 
cending to a thousand meters which is built up essentially fro^m Paleo- 
zoic rocks. In the north it strikes NW, in the south SW, and here it 
is in contact with eruptive masses metamorphosed to gneisses. These 
changing strike directions NW and SW are given also in the Etschigo 
mountains and throughout in the entire area which lies southwest from 
the Abukuma gneiss zone extended in our sense to the northward. It 
