Vol. 6, 1920 
PETROLOGY: G. P. MERRILL 
453 
characteristic of both oHvine and enstatite chondrules, while the barred 
forms, such as are shown in figures 6 and 7, are hmited mainly, if not 
wholly, to monosomatic forms composed of olivine. In figure 6, from the 
FIG. 5 
Beaver Creek stone, the white portions are olivine which extinguish 
practically as a single unit; the black portions are glass. It is to be 
noted that the outlines, though sharp are not smooth as in those described 
above, but have projecting particles extending out into the ground; also 
FIG. 6 
that this border portion often contains enclosures. In figure 7 from the 
Henderson ville stone, the bars are bent and curved and do not all ex- 
tinguish simultaneously, as the stage is revolved, the dark cloud sweeping 
