PLATE L 



Fig. 1. — A fine coni2'>act basait, with comparatively large 

 plienocryst of olivine wliicli is more or less iddingsitized. The 

 ground-mass consists of small ci-ystals and grains of angites, 

 granular olivine and the laths of plagioclase, with the structure 

 typically granulitic. Bo-ryo-san, Haku-sha Island. P. oo. 



Fig. 2. — The same rock-type as the preceding, but rather 

 coarse. On the right side in the figure is a augititic patch, 

 composed of exclusively the crystals of augite in the base. Hoko 

 Island, r. :]:}. 



Fig. ^^ — Olivine-less basalt from Ilatto, ^^outhern Group, 

 and it probaldy l)elongs to the same type as Figs, o and 4 in 

 Plate TL A doubtful olivine is present in the form of chloritic 

 patches, but no visible hypersthene. Cleneral mass consists of a 

 plexus of fine grains of augite and fine laths of plagioclase in 

 the base. This is quite an anomalous rock. P. 3*). 



Fig. 4. — Iddingsite-l)earing basalt with a large idiomorphic 

 olivine, externally changing into iddingsite. Magnified ()-") diame- 

 ters. Hoko Island. V. ^.l. 



Fig. "). — Rock belonging to the same type as the preceding. 

 It is also from Hoko Island. Olivine on the left side of the 

 figure shows various stages of iddingsitization. 



Fig. (). — Also iddingsite-bearing basalt, with olivines chang- 

 ing from the interior, as may be seen on the lower side of the 

 figure. ]\Iagnified 38 diameters and not <;">, as is stated in the 

 Plate. Niçois crossed. Kippai Island, 



