NOTES ON THE MINERALS OF JAPAN. 231 



forms, is equally well observable in specimens from both 

 places. 



The occurrence of Tridymite at Maekakeyama, a part of 

 AsAMA Volcano, is rather rare. 



35. Rutile. 



Of this mineral a single bad specimen of prismatic form, 

 and another small crystal, both from Takayama in Mino Pro- 

 vince, are found in Wada's collection. They are of a dark brown 

 colour. 



36. Cassiterite. 



Takayama, &c., in Mino. — The tin placers of this granitic 

 region, which are now nearly exhausted, gave wolframite, sap- 

 phire, fergusonite, magnetic iron sand, topaz crystals with rounded 

 edges, &c. Many of the larger specimens of cassiterite are about 

 1 cm. in diameter, but mostly smaller. They have sometimes 

 quite well preserved edges and show the usual cyclical twins on P go. 



Taniyama in Satsuma Province. — In the tin mines of this 

 locality cassiterite is found in massive form and associated with 

 wolframite. 



KiUEA in Bungo Province. — Here, cassiterite crystals are 

 found in a brown-coloured detritus filling up cavities in cry- 

 stalline limestone ; massive specimens of cassiterite are also 

 found along with arsenopyrite, &c,, ia veins through limestone, 

 hornfels, &c. 



Hitachi Province. — Wada possesses a beautiful druse of 

 crystals of cassiterite, each about 1 cm. in diameter ; it is said to 

 have been obtained at Takano in this province. 



