f9i4-] CONCEPTION AND TRINITY BAYS, NEWFOUNDLAND. 389 



ground mass. These spherules measure as small as 9 microns in 

 diameter but have an average diameter of between 30 and 40 mi- 

 crons (Fig. II and 12, Slide 292). 









•^ '■#3r - 



%■ 



.•"ras^C- 



Fig. 13. Middle portion of manganese zone in Manuels brook. The num- 

 bers are those of the section. 



