CHAZIAN AND MOHAWKIAN SERIES 691 



major, Phylloporina cf. sublaxa, Nichohonella, Batostoma varium, Erido- 

 trypa mutahilis, ^Orthis ignicuJa, ^Fleheiiella exfoliata ?, Clitamhonites 

 piger, *Lept(Fna incrassata (rare), ^Eafinesquina champlainensis, Stro- 

 phomena (group of S. sulcata), Rhynchotrema ( ?) orientalis, ^Cama- 

 rella varians, *(7. longirostra, Zygospira (small finely plicate form), 

 Machirites atlanticus (cf. M. higshyi, a Lowville guide fossil), "^Eccyli- 

 omphalus cf. fredericki, ^Rapliistoma striatum, ^E. stamineum ?, Tetra- 

 nota near bidorsata, Oncoceras cf. lyceuui, Poterioceras, Cameroceras, 

 ^Spyroceras cf. clintoni, ^Plectoceras jason, Leperditia two species, 

 "^Bumastus globosus, "^Tlialeops clavifrons, "^Isotelus harrisi, Illcenus hay- 

 fieldi, ^Pliomerops canadensis, ^Pterygometopus annulatus, BathyureUus 

 fraternus, Bathyurus angelini, and ^-Eoharpes cf. antiquatus. 



The following additional species described by Billings are thought to 

 be from this zone, and not from the "Calciferous,^* as he states : Cono- 

 cardium hlumenhachi, Pleurotomaria dbrupta, P. misera, Helicotoma 

 perstriata, CoeJocaulis linearis^ Solenospira prisca, Lophospira aspera, 

 Cyrtoceras maccoyi, Plectoceras tyrans, and P. natator. 



The higher beds of Mingan A3 have as 3^et yielded no fossils. 



Mingan formation. Zone A^. — On Large Island, to the south of the 

 concealed zone that is established by Eichardson at about 56 feet, are 

 seen 5 feet of the brittle limestone thought to be the top of the 45 feet of 

 limestone composing zone Mingan A3. This is followed by 45 feet of 

 light drab, dense, "birdseye"-like limestone that weathers into the fan- 

 tastic forms referred to by Eichardson^^ as the "flower pot rocks." No 

 determinable fossils were seen here, but on one of the smaller of the 

 southeastern islands in the Parroquet group a few fossils were obtained 

 in the lower half of this zone. These are Orthis ignicula, Camarella 

 varians, Bathyurus extans, and Bumastiis cf. globosus. 



It is probable that some of the highest strata of Harbor Island also 

 belong here and, as well, 35 feet of the lowest beds of Bald Island, as at 

 this place "flower pots" occur, but at neither of the two places have these 

 deposits yielded fossils. 



Mingan formation, Zone A^. — The previous zone of Large Island is 

 followed farther south on the same island b}^ from 35 to 40 feet of light 

 colored, dense, brittle limestone, also having more or less of a "birdseye" 

 character. It forms Tower Eock and the south end of Large Island. 

 Few fossils were collected, among them being Leperditia, Thaleops clavi- 

 frons, Bumastus globosus, and Bumastus erastusi. 



Billings records here the presence (probably from the topmost beds) 

 of Maclurites logani, Euconia amphitriie, Cyrtoceras subturbinatum, 



" Richardson : Report of Progress, Geological Survey of Canada, 1857, p. 242. 



