PLATE IV. 



DESCRIPTION OF THE MICR0PH0T0GRAPH3. 



Etch-figures are illustrated as follows : — 



No. 13. Pits on (010), Ala Diopside, HF. X 78. 



No. 14. Pits on (010), basaltic Hornblende from Kafveltorp, HF. x 78. 



No. 16. Pits on (100), Diopside from Ala, HF. X 78. 



No. 16. Caustic soda pits on (110), Wolfsberg basaltic Hornblende. X 78. 



No. 17. Caustic soda pits on (110), basaltic Hornblende from Kafveltorp. 



X 225. 

 No. 18. Pits on (110), Diopside from Ala, HF. x 78, 



