Tectonic Gcoi:;raf^liy of liastcni Asia. — Hobbs. 219 
mately ^o niimites of latitude farther to the nortli, hut a complete 
degree of longitude further east the Kitakami mountain region begins, 
somewhat longer, somewhat higher, and somewhat broader than the 
above mentioned, but of similar rhomlwidal to elliptical form. It con- 
sists of Paleozoic sediments, whose age, as everywhere in Japan, is 
with the exception of the Carboniferous part indeterminable. The 
strike directions of the internal structure are in gener.ii NNVV to N by 
\V, but in the southcm part irregularities occur. Here a southwardly 
directed .syncline of Trias and Jura appears; at the ooint of the penin- 
sula formed by it occur also Paleozoic beds with S by W strike. Gran- 
ite and other ancient eruptive rocks take part ii^i the makt-up of the Kit- 
akami. 
If the relations in age are here widely different from those of the 
Abukiuna it is also true that differences are found in reference to the 
form of the coast line. In contrast to the broad Tertiary band and the 
even coast line of the Abukunia is found in the Kitakami an unusually 
well developed Rias-like projection of the coast and the absence of the 
Tertiary on the coast side. There the evidence of negative transla- 
tion of the coast line, here the significant marks of advancmg bay-like 
invasion of the sea into the valley outlets. 
The question of the contrasting relations of these two mountain 
masses is decisive for the conception of North Japan. When the as- 
signed differences in structure and constitution were still unknown, 
Naumann was able tc arrive at the view that both masses wer.o sep- 
arated members of a continuous zone, and that the step-like pushing-out 
of the ridges of the northern members came about in such a manner 
that along a transverse line extending from Sado to Sendai a pushing 
out in an easterly direction of the entire northern part of North Japan 
in contrast to the southern had taken place. This conception deter- 
mined the drawing of his median line to the west oi both mountain 
masses, and this has, moreover, led up to the generally accepted a iew. 
Since .A.bukuma has been investigated Kitakami can no longer be 
considered as its continuation. Both masses are much more clearly 
fragments of two parallel but different zones in the basement cf the 
-?nge. and particularly worthy of note because ancient intrusive rc-cks 
are rare in them and younger ones are almost entirely lacking. If we 
wish to search out the actual further course of both zones toward the 
north, following individually the strike direction of th? fold .struc- 
tures of each of the two masses, we must disregard all later coverings 
by volcanic masses and Tertiary sediments. The places where the base- 
ment is exposed are indeed rare, but by the study of the geological m?p 
thev are found to group them.selves in two zones which run diagonally 
through North Japan in the direction N by N W to NNW. The di- 
rection of the Abukuma zone is brought out by the contimiation of the 
parallel lines which limit the rhomboid of the Abukum.i massif on the 
southwest and on the northeast, and which are followed also by the 
small ranges and the dikes of eruptive rocks in it. \Vc come over the 
bro-ul valley of the Abukuma river and find between the extended lines 
