118 



Report of the State Geologist. 



themselves are most. closely related, similar tendencies to departure from the 

 normal in provinces so remote, as are evinced by these varieties, are 

 worth v of note. 



ToRNOCERAS PERACUTUM, Hall (sp.). 



The original fragment of the species described and figured in Palaeon- 

 tology of New York, vol. v, part 2, p. 463, pi. lxxix, fig. 8, was taken from the 



Portage rocks at Ithaca, The species was one of 

 large size, closely umbilicated and has a suture dif- 

 fering from that of Tom. uniangulare in its promi- 

 nent loop-shaped lateral lobes and acute ventral sad- 

 dles. This is shown in the accompanying figure 

 and it will be seen that the outline is a natural 

 extreme of development from the suture of the 

 typical Torkoceras. The species may be directly compared in size and form 

 of suture to Ton/, mithracoides, Freeh, from the upper Devonian of Nassau.* 



Figure 86. Tornoceras peracutum 

 Tbe adult suture. 



Tornoceras bicostatum, Hall (sp.). 



Plate VIII, Figs. 4-13. 



1843 Goniatites bicostatus, Hall. Geology of New York; Rept. Fourth 



Dist., p. 246, fig. 107-8 (p. 245). 

 1860 Goniatites bicostatus, Hall. Thirteenth Ann. Rept, N. Y. State Cab. 



Nat. Hist,, p. 103, figs. 19-20. 

 187'» Goniatites bicostatus, Hall. Illustrations of Devonian Fossils, pi. Ixxii, 



figs. 8-10; pi. lxxvi, fig. 1. 

 1 8 7 ' » Goniatites bicostatus, Hall. Palaeontology of New York, vol. v, pt, 2, 



p. 450, pi. Ixxii, figs. 8-10; pi. lxxiv, fig. 1. 

 1885 Goniatites bicostatus, Clarke. Bull. TJ. S. Geol. Surv. p. 49, 



The original figures of this species given in the Report on the Fourth 

 Geological District of New York, show that the specific name was based 

 upon the strong revolving hyponomic ridges, but both these figures and those 

 subsequently given in volume v, part 2, Palaeontology of New York, indicate 

 that all illustration of these features has thus far been based upon compressed 

 specimens in w hich the broad, flat venter has been turned to one side and 

 hence the revolving ridges been made to appear as though the)' appertained 



•Fhech, Geologic der Umgegend von Haiger bel Dillenburg (Nassau), p. 30, figs, la, a, b, 3, 1887. 



