1912] 



The Ottawa Naturalist. 



99 



Bumastus miller i (Billings), Lowville and Black River, rather 

 common, A. 

 indcienninatus (Walcott), Black River, rather rare, E. 

 billingsi Raymond and Narraway, Trenton, rather 

 rare, C. 



Thaleops ovata Conrad, Black River, common, C. 



Calymene senaria Conrad, Trenton, abundant, A. 

 Cybele ella Narraway and Raymond, Black River, very rare, C. 

 Ceraurus pleurexanthemus Green, Black River to Utica, common, 

 B. 

 dentatus Barton and Raymond, Trenton, rare, D. 

 bispinosus Barton and Raymond, Black River, very 

 rare, E. 

 Dalmanites achates Billings, Trenton, rather common, C. 



bebryx Billings, Trenton, rather rare, C. 

 Pterygometopns callicephalus (Hall), Black River and Trenton, 



common, C. 

 Amphilichas trentonensis (Conrad), Trenton, very rare, F. , 



cucullus (Meek and Worthen) , Trenton, very rare, E. 

 Arges wesenbergensis paulianus Clarke, Trenton, rather rare, E. 

 Encrinurus vigilans Hall, Trenton, very rare, C. 

 Bronteus lunatus Billings, Trenton, rather rare, B. 

 Odontopleura trentonensis (Hall), Trenton, rather rare, C. 

 Proetus parviusculus Hall, Trenton, rather rare, D. 



A. Entire specimens common. 



B. 



C. 



D. No 



E. " 



F. " 



sometimes, but usually fragmentary, 

 very rarely, but usually fragmentary, 

 always fragmentary, 

 generally cephala or cranidia. 

 pygidia. 



Summary. 



In all 43 specimens of 22 genera distributed as follows: 

 In Chazy formation . . 

 " Pamelia formation 



Lowville formation 



Black River formation 



Trenton formation 



Utica formation . . . 



Lorraine formation 



Entire shields have been found of 26 species; 17 species are 

 still known only from fragments. 



The compiler has endeavoured to eliminate all doubtfully 

 or incorrectly identified species, and to bring the nomenclature 

 up to date, thus establishing a list which may be relied on as a 



