NOTES ON THE MINERALS OF JAPAN. 277 



Ogasawarajima. — Druses of white prismatic crystals of 

 apophyllite with oP, coPcc and P (?), (besides cop,, and iP, 

 accordiug" to Ko), are found with heulandite in a green earthy 

 mass of an altered eruptive rock (?). Basal sections of the 

 crystals sometimes measure about 1 cm. or more in diameter. 

 Some of the crystals show distinct " Andreasberg-rings," but no 

 division into sectors in crossed Niçois. Others show biaxial inter- 

 ference figures, no division into sectors is there observed, but an 

 intergrowth of irregular patches with a different orientation is 

 found in the principal crystal substance. 



Reddish- white apophyllite crystals of a more minute size are 

 comparatively rare at the same locality. They show a combi- 

 nation of oP. P. œPcc, and are nearly like the white crystals 

 in the different phenomena of optical anomaly they exhibit. 



The white crystals of Ogasawarajima have been analyzed. 



125. Analcime. 



Maze in Echigo, which is the most well-known locality of 

 Japanese analcime and apophyllite, gives crystals of the former 

 mineral always in 2O2 , with often striated faces and sometimes 

 modified by cc O co at their solid angles. The mineral is colour- 

 less to greenish-white and is sometimes 2.5 cm. in diameter. 

 Sections parallel to c» O '^, taken from the outer part of the 

 crystal, usually show four sectors, besides rarely a central 

 one. Similar sections from the middle of the crystal show eight 

 subdivisions. Those parallel to O and taken from near the 

 surface show three or six sectors ; and those parallel to 2O2 and 

 from the surface are often divided into three parts instead of 

 being quite homogeneous. Double refraction is originally strong, 

 and becomes stronger by heating. 



