PLATE III. 



DESCRIPTION OF THE MICBOPHOT06RAPHS. 



Etch-figures are illustrated as follows : — 

 No. 7. The same as No. 6 on another crystal, showing the common distortion 



of the pits, HF. X 78. 

 No. 8. Caustic soda pits on Philipstad Hornblende (110), (crystal face). X 225. 

 No. 9. Caustic soda pits on Philipstad Hornblende (UO), (cleavage, inner 



zones). X 225. 

 No. 10. Etch-hills on (110), basaltic Hornblende from Mayenegg (HF gas). 



X71. 

 No. 11. Pits on (110), Arfvedsonite from Kangerdluarsuk, HF. X 78. 

 No. 12. Pits on (010), ZUlerthal Actinohte, HF. x 78. 



