The American Geologist, Vol. XXXIII. 
Plate XXVIII. 
Fig. 11. Thin Seceion ot Dioryte-Porphyry as seen under a 
microscope between crossed nicols ■ 35 (Kossland 13). 
1 2. Thin Section of Dioryte-Porphyry as seen under a 
microscope in ordinary light (Rossland 13). 
