lsas-1902. No. 28. 



THE CAMBRO-OKDOVICIAN BEDS. 



11 



In addition to the forms mentioned here we have some others, 

 brachiopodes, gastropodes, trilobites etc, where the material before us 

 has been too' incomplete for determination. 



The vertical extent of these forms as known from other regions of 

 North America is as follows: — 



Cha- 

 zyan 



Black 

 River 



Trenton 



Cincin- 

 natian 



Halyites catenulatus var. gracilis Hall . 

 Calapcecia canadensis Billings .... 

 Streptelasma corniculum Hall . . . 

 Mesutrypa cf. discoidea. var. orientalisExssi. 

 Callopora angularis Ulrich . . 

 Bafinesquia deltoidea Conr. ... 



Plectainbonites sericea Sow 



Orthis tricenaria Conr 



Triplesia sp. . ... 



KJiynchonotrewia inwqvivalvis Casteln. 

 Trochonema cf- umbilicahim Hall 



Gonioceras occidentale Hall 



Tlialeops ovata Conr . 



Nileus (Bumastus'?) sp 



Leperditia fabulites Conr 



+ 



+ 



+ 



cf 



+ 



cf 



We have here a typical TVewiow fauna with a series of the charac- 

 teristic forms of this division, besides some which are found in 

 considerable vertical extent. The fauna exhibits an extremely close 

 agreement with that described by Schuchert from Silleman's Fossil 

 Mount in Baffin Land, i which again with its 72 species lies very close 

 to the Galena fauna in Minnesota, Iowa, and Wisconsin. 



Norman Lockyer Island was visited by Sir George Nares's expe- 

 dition, and in the account given by Fell den and De Ranee (p. 558), 

 Favistella (Columnaria) reticulata Salter is mentioned from there. 



According to Schei the limestone from Norman Lockyer Island 

 recurs on the north side of the Princess Marie Bay : 



"The same limestone, with the same fossils, occurs again at the 

 foot of Cape Harrison, where however it is overlain by thick beds of 

 limestone, calcareous sandstone, quartz .sandstone, and on top of all a 



1 On the lower Silurian (Trenton) Fauna of Bafliii F.aiid. Proc. U. S. Miis. 

 XXII 1900. 



