CEPHALOPODA . 
221 
In 1858 Mr. Jules Marcou described Orthoceras Nova-Mexicanum, from the 
Lower Carboniferous {Geol. North America). 
Mr. Hall described Orthoceras epigrus, from the Lower Carboniferous {Trans. 
Alb. Inst., vol. 4). 
Prof. G. C. Swallow described 0. aculeatum, 0. moniliforme (not 0. moniliforme, 
Hall, 1847) and 0. occidentale, from the Coal Measures; and 0. Kickapooense, 
from the Upper Permian {Trans. St. Louis Acad. Sci.). 
In 1859 Mr. Billings described Orthoceras Antenor, 0. Maro and 0. Shumardi, 
from the Chazy group; 0. Becki, 0. deparcum, 0. Lamarcki (== Endoceras 
Lamarcki), 0. Montrealense {=Endoceras Montrealense) and 0. sordidum, from the 
Calciferous group {Canadian Nat. and Geol., vol. 4); also 0. Simpsoni, from the 
Silurian {Geolog. Surv. Canada: Rep. of Progr.). 
Mr. Hall described Orthoceras clavatum (—0. desideratum, H., 1877), 0. Helder- 
bergiw, 0. longicameratum, 0. pauciseptum, 0. perstriatum, 0. rigidum, 0. rude, 
0. subtextile and 0. temiannulatum, from the Lower Helderberg group; .and 
0. arenosum, from the Oriskany sandstone {Patdeontology of New York, vol. 3). 
In 1860 Prof. J. W. Dawson described Orthoceras elegantulum, and 0. exornatum, 
from the Upper Silurian {Canad. Nat. and Geol., vol. 4). 
Mr. Billings described 0. pertinax, 0. tenerwn and Endoceras rapax, from the 
Black-river group {Canad. Nat. and Geol., vol. 5). 
Mr. Hall described Orthoceras punctostriatum, from the Upper Silurian {Canad. 
Nat. and Geol., vol. 5); 0. medullare and 0. columnare {=Orus, H., 1877), from 
the Niagara group {Geolog. Surv. Wisconsin: Rep. of Progr .); and 0. Indianense, 
from the Goniatite limestone of Rockford, Indiana {Thirteenth Rep. on N. Y. 
State Cab. Nat. Hist.). 
Prof. Swallow described 0. Chemungense, from the Chemung, and 0. Chou- 
teauense, from the Chouteau group {Trans. St. Louis Acad. Sci.) 
Mr. F, B. Meek described 0. baculum, from the Lower Carboniferous {Proc. 
Acad. Nat. Sci. Phila.). 
Messrs. F. B. Meek and H. A. Worthen published 0. expansum, from the St. 
Louis group {Proc. St. Louis Acad. Sci.). 
