-2^Q B. KOTO. 



down to a lower level, along the meridional line of dislocation. Con- 

 sequently tlie ofrnnnlated and compressed varieties — the schistose 

 g-ranites — are confined to the above-mentioned tectonic lines, one alno«' 

 the Pacific sea-board, and the other along the Abnknma valley, as 

 may be cleai'ly understood from the diagram, ])age 232. 



I have repeatedly spoken of the yonng and old gr-niites which 

 are by no means easily distinguishnlile from one another. They occur 

 in such a confused mnnner as to try the patience of even careful olv 

 servers; and many have entirely ignored the heterogeneous origin of 

 the two kinds of massive rocks. The best exposure, illustrative of 

 the mode of occurrence of the vouna:er biotite and rdder hornblende 

 granite may be found between IsliiknM^a-yama and Shimo-Kawabe, 

 where the two apjiear successively between the line of fiult after the 

 manner of ruin-marbles (Fig- 5, PI. XXIV), and moreover assume 

 at times a schistose structure. In this exprosure, it is clear that one 

 is the dyke-rock to the other, but the granites being developed in 

 almost e([u:d masses it is not easy to say which is the country-rock 

 and which the intruding one. Another very illustrative profile is 

 shown in Fig. I, PI. XX^^ in which such complicated modes of 

 occurrence of the granites are to be seen that their mutual relations can 

 not be easily determined. 



Judging from the wide distribution of the hornblende-granite, it 

 seems to form the general foundation of the Abukuma plateau, upon 

 which are built up all the later formations. If this be the case, then 

 the hornblende -granite in the first section inust be the country-rock 

 through which the biotite-granite made its irruptions at several points, 

 the older one being itself already in Û\e solid state. In the second 

 section tlie same cannot be said ; for the two granites intermingle with 

 one another in such îi manner as to lead one almost to suppose that the 

 hornblende-bearing varietv must have been in a more or less plastic 



