Fig. 367. — Schistose structure developed by pressure shown in the left half of the 

 figure, while it is wanting in the right half. The vertical line is a bedding plane. 

 The layer to the left was of sufficiently different composition or subject to sufficiently 

 different movement to develop schistosity, while that to the right was broken 

 (brecciated) instead. The rock at the left would be called quartz schist, while 

 that at the right is quartzite. Huronian formation near Ableman, Wis. (Atwood.) 



(Page 445.) 



