102 



Orthoceras annulatum, Whitfield 1882. Geol. Surv. Wisoons., vol. 



IV., pt. 3, p. 298, pi. 19, fig. 1. 



Whiteaves 1884. This volume, pt. 1, p. 38. 



Orthoceras a?i7iulatum,vaT. Americanum, Foord. .IS88. Cat. Foss. Cephal. Brit. 



Mus. , pp. 56 and 57. 



Hespeler and Elora : the two specimens referred to on page 38 of the 

 first part of this volume. 



Mr. Foord (op. cit., p. 57) thinks " that there exist sufficiently well- 

 marked characters in the American form of 0. annulatum to make it 

 desirable to sep irate it from the European one," and he accordingly proposes 

 a local designation for the former. " The characters," he says, " by which 

 the variety Americanum is distinguished from its European allies reside in 

 the surface ornaments. These consist of transverse elevations, partaking 

 more of the nature of undulations than of ribs, and becoming in some 

 places indistinct or even obliterated. The undulations are generally wider 

 than the spaces separating them, being at a distance of about one-sixth 

 the diameter. The fimbriae are coarse, as in the variety crassum, but 

 with their arches or festoons much wider apart. Three or four only 

 occupy the spaces between the undulations. The longitudinal elevations 

 are sometimes so strong as to cause a nodose appearance ; but this is not 

 always the case, as I have a specimen befoie me in which they are very 

 obscure. The rate of tapering in a somewhat flattened example from 

 Canada, measured along its broader diameter, is 1 in 17." 



GOMPHOCERAS SEPTORE, Hall. 



Gomphocera-i septoris, Hall 1867. Twentieth Rep. Reg. N. Y. St. 



Cab. Nat. Hist., p. 350, figs. 9 and 10. 

 Cyrtocerai septoris. Hall and Whitfield. .1875. Rep. Geol. Surv. Ohio, vol. II., 



pt. 2, p. 151. 

 " " Whiteaves 1884. This volume, pt. 1, p. .39. 



Elora, R. Bell, 1861 : the cast of the body chamber referred toon page 

 39 of the first part of this volume. The six lateral sinuses and azygos 

 dorsal sinus in the aperture of this specimen clearly show that it belongs 

 to that section of the genus Qomphocerds which Hyatt has separated under 

 the name Septamerocerasy- This latter genus is said to be founded upon 

 a species in the Museum of the Geological Survey of Canada, the Gom- 

 phoceras inflatum of Billings, but G. injlatum is a mere manuscript name, 

 which has never been published, attached by Billings to a rough cast of 

 the interior of the body chamber of a shell, with the aperture badly pre- 

 served, from the Silurian (Upper Silurian) rocks at L'Anse a la Barbe, 



*G-enera of Fossil Cephalopods. Proo. Boston Soc. Nat. Hist., April, 1883. vol. 

 XXII., p. 278. 



