CEPHALOPODA. 223 



Prof. Swallow described 0. Cheslerense, from the St. Genevieve group = Car- 

 boniferous (Trans. St. Louis Acad. Sci.). 



Prof. Winchell described 0. heterocinctum and 0. Whitei, from the Kinder- 

 hook group = Waverly group (Proc. Acad. Nat. Sci. Phila.). 



In 1865 Mr. Billings described O. Atticus, 0. Catalina, 0. Cato, 0. Catullus, 

 O. exploralor, 0. Flavins, O. hczsitans, 0. Missisquoi, 0. Perseus, 0. piscator, 0. 

 Priamus, 0. repms, 0. Sayi, 0. servile, O. Tityrus and 0. Xerxes, from the Quebec 

 group ; 0. dijfidens, 0. Drummondi and 0. velox, from the Chazy group ; 0. edax, 

 O. furtivum, 0. Glaucus, 0. indagator, 0. ordinatum and 0. veterator, from the Cal- 

 ciferous group (Palaozoic Fossils). 



 Meek and Worthen described 0. crebristriatum and 0. Jolietense, from the 

 Niagara group (Proc. Acad. Nat. Sci. Phila.). 



In 1866 Mr. Billings described 0. bellatulum, 0. infelix and 0. Medon, from 

 the Clinton group ; 0. Brontes, 0. Cadmus, 0. Oberon, 0. Pylades, 0. Remus and 

 0. Varro, from the Niagara group ; 0. Crocus and 0. fulger, from the Hudson- 

 river group ; 0. ferum and 0. Sieboldi, from the Hudson-river and Anticosti 

 groups ; and O. pileolum and O. raptor, from the Medina group (Catalogue Silur. 

 Foss. Anticosti). 



Prof. H. B. Geinitz described 0. cribrosum, from the coal measures (Carb. und 

 Dyas in Nebraska). 



Mr. H. A. Worthen published 0. subaculum (not defined), from the Niagara 

 group (Geolog. Surv. Illinois, vol. 1). 



Messrs. Meek and Worthen described 0. Winchelli, from the Devonian (Proc. 

 Acad. Nat. Sci. Phila.). 



Mr. Winchell described O. pustulosum, from the Hamilton group (Rep. Lower 

 Penin. Mich). 



M. J. Barrande described Orthpceras (Endoceras) Rottermundi, from the Trenton 

 limestone; and Huronia distincta (=Huronia sp. ? Stokes, 1840), from the Nia- 

 gara limestone (Sysl. Silur. du centre de la Boheme). 



Mr. Hall described 0. abnorme, 0. alienum, 0. crebescens, 0. Niagarense, and 

 recognized O. angulatum, of Wahl., from the Niagara group; also 0. Loxias, 

 from Lower Silurian (Twentieth Rep. N. Y. State Cab. Nat. Hist.). 



