PICRITE FROM Mt. HORROR. 



W. H. TWELVETREES, Photo-micro, 



EXPLANATION OF FIGURE. 



AUGITE-PICRITE from Mt. Horror, x 45. Transmitted 

 light. At the bottom of figure is part of a large 

 augite crystal with lines of inclusions marking 

 zonal growth. The large rounded white crystals 

 are olivine. The narrow laths are the felspars. 

 The rest of the field comprises the smaller augites 

 and serpentinous substance. 



