339 



Opercula. 



Several detached multispiral and paucispiral opercula, of unknown 

 genera and species. 



Cephalopoda. 

 Orthoceeas ckebescens, Hall. 

 Orthockras Selwyni, Billings. 

 KlONOCEEAS cancellatum (Hall). 



KioNOCEBAS medullare (Hall). 



Orthoceras ■meduXlare, Hall 1860. Rep. Progr. Geol. Surv. Wisoons. for 



1859, p. 4; and (1867) Twentieth Rep. 

 Reg. N. York St. Cab. Nat. Hist., p. 353, 

 pi. 20 (11) figs. 1 and 2. 



I. M Whiteaves 1884. This volume, pt. I, p. 37; and (1895) 



pt. II, p. 99. 



Kionoceras medullare, Clarke & Ruedemann . 1903. N. York St. Mus., Mem. 5, p. 86, pi. 



10, fig. 23. 



KlONOCEEAS Daewini ('Billings). 



Orthoceras Darwini, 'BiWm^B 1862. Geol. Surv. Canada, Palieoz. 'Foss., 



vol. I, p. 161. 

 Oyrtoceras Myrice, Hall and Whitfield 1875. Geol. Surv. Ohio, Palseont., vol. 2, pt. 



2, p. 149, pi. 8, fig. 9. 

 Orthoceras Darwini, White&vea 1884. This volume, p. 38, pi. 6, figs. 2 and 



2 a. 



Cyrtoceras Myrwe, Whiteaves 1884. Idem, p. 39, pi. 6, figs. 3 and 3 a. 



Orthoceras Barwini, Foord 1888. Cat. Foss. Cephal. Brit. Mus., pt. I, 



p. 76, fig. 8. 



II II Whiteaves 1895. This volume, pt. II, p. 100. 



i'iomoccj'os i>a)'M)mj, Clarke and Ruedemann. .1903. N. York St. Mus., Mem. 5, p. 84, 



pi. 10, fig. 22 ; pi. 11, fig. 6 ; and pi. 12, 



figs. 1-8. 



Dawsonoceras annulatl'm, Sowerby, 

 var. Ameeicanum, Foord. 



Orthocetas annulatum, var. Americanum. 



Foord 1888. Cat. Foss. Cephal. Brit. Mus., pt. I, 



pp. 56 and 57. 

 Orthoceras annulatum, var. Americanum, 



Whiteaves 1895. This volume, pt. II, p. 101, which 



see for a list of synonyms of this shell, 

 with references. 

 Dawson oceras annulatum, var. americanum, 



Clarke and Ruedemann 1903. N. York St. Mus., Mem. .5, p. 81, 



pi. 10, figs. 19-21; and pi. 11, fig. 1. 



7 



