I9I4.] CONCEPTION AND TRINITY BAYS, NEWFOUNDLAND. 391 



green shale overlies this fossiliferous layer and this in turn is fol- 

 lowed by nodular green shale containing manganiferous calciite 

 nodules, a description of which is given in connection with the 

 following bed. 



Fig. 15. Photograph, natural size of ground and polished horizontal sec- 

 tion of shale containing manganese carbonate nodules from 219 A4. 



219 A 4 is a conspicuous rhodochrosite and manganiferous cal- 

 cite nodular bed and may be considered the base of the manganese 

 zone at Manuels (Fig. 13). Structurally this is a nodular and oolitic 

 bed, the former structure conspicuously observable macroscopically, 

 and the latter, though not so well defined a structure, observable 

 microscopically. The entire bed measures 5.1 feet in thickness and 

 is divisible into two members, a and b. The lower member, 219 A 4a 

 is a predominantly nodular reddish green shale while the upper divi- 

 sion or b member is not so nodular. 



