J. C. ir. na)vfre]j. 
Jr'His. 
O 
, J, r,>J. 200. 
Fig. 8. Slip-liiie.s x ICO. 
FiiT. 9. Fart of a siiiii'le ery.stal after sti'aiiiiiii’' 
O “ t' O 
ill tension ami re-etching x 4.'). 
Fig. 12. Twins in strained crystal x 45. 
Fig. 10. Strained erystal, re-etched x li. 
Fig. 11. Other face of same crystal x 0. 
