CANADIC PERIOD 527 



feet thick. Fort Cassin horizon. Has Rhinopora prima, Dalmanella 

 evadne ?, Protorthis cassinensis, P. minima, Hemipronites apicalis, Bil- 

 lingsella (?) primordialis, Syntrophia lateralis, Tryblidium (4 species), 

 Cliospira lirata, Euomphalus circumliratus, Raphistoma, Plethospira cas- 

 sina, Lophospira cassina, Ecculiopterus volutatus, Calaurops lituiformis, 

 Fusispira obesa, Maclurea affinis, Orthoceras in many species, Cyrtoceras, 

 Gomphoceras, Piloceras explanator, Eurystomites kelloggi, E. imperator, 

 Tarphyceras champlainensis , T. farnsworthi, T. seeleyi, Schroederoceras 

 eatoni, Trocholites internastriatus, Asaphus canalis, Bathyurus (?) see- 

 leyi, Harpes cassinensis, Nileus striatus, Ribeiria compressa, R. ven- 

 tricosa. 



D3. Sandy thin-bedded limestone, 120 feet thick. 



D2. Magnesian limestone with some sandstone, 75 feet thick. Has at 

 Phillipsburg, Canada, Syntrophia armanda, Orthoceras (7 species), Cyr- 

 toceras aristides, and Dikelocephalus missisquoi. 



Dl. Thin-bedded blue limestone, 80 feet thick. At base has Ophileta 

 complanata, Near Beekmantown, Whitfield (1889) collected in this 

 zone Dalmanella macleodi, Tnplecia ( ?) radiata, Maclurea ( ?) sordida, 

 Hormotoma gracilens, Lophospira calcifera, Liospira prcevium, Trocho- 

 nema exile, Euconia beelcmanensis, E cculiomphalus ( ?) priscus, Metop- 

 toma (?) alta, Tryblidium pileolum, T. (?) acutum, Holopea turgida, 

 Bathyurus conicus, B. seeleyi, and Cyrtoceras (2 species). 



C. Dolomite, magnesian limestone, and sandstone, together 350 feet 

 thick. Toward the bottom has Scolithus minutus. 



This same fauna is also known at Phillipsbnrg, Quebec; again in part 

 on the Mingan islands; and finally in great development, but with local- 

 ized species, in northern Newfoundland, in zones F, G, H, I, K, L, M. 

 The facies of these various Canadic faunas are unknown in Europe. 



In Pennsylvania, around Chambersburg and Mercersburg, Ulrich re- 

 ports that this system has at least 2,500 feet of pure magnesian limestone ; 

 farther west at Bellefonte, in the central part of the state, over 4,000 feet. 

 In the southern Appalachian area, the period is present in the Knox of 

 Alabama and in the Wells Creek uplift of western Tennessee. The latter 

 area is most closely related faunally to the Yellville of northern Arkansas. 

 In the upper Mississippi valley there are no Canadic deposits, yet in the 

 Mohawk valley of New York the upper portion of the Little Falls dolo- 

 mite belongs to this period. In the southern Cordilleran region these 

 strata are likewise present, but north of Colorado the evidence is rather 

 against their existence. 



A fauna entirely different in character, preserved in black shales and 

 sandstones, occurs in the Levis trough of the Saint Lawrence sea. Here 



