INDEX TO FOSSILS OF NIAGARA GROUP. 399 



M. hercyna [?] Billings 345 



com])are Pleurotomaria gonopleura, W. and M. 



M. laphami, Hall, Geol. Rep. Wisconsin, p. 36. 18G1 366 



•Holopea chicagoensis, TV. and M., Mem. Bost. Soc. Nat. Ilist., Vol. i, pa. 99, 

 pi. 2, f. 18. 



H. guelphensis, Billings 343 



H. harmonia ? 342 



•H. niagarensis, "W. and M., Mem. Bost. Soc. Nat. Ilist., Vol. i, pa. 99, 



pi. 2, f. 17. 



Tremanotus alpheus, Hall 347 



= Bellerophon (Bucania) perforatuSjW. and M. 

 *PlatyGeras campanulatum, W. and M., Mem. Bost. Soc. Nat. Hist., Vol.i, pa. 99, 



pi. 2, f. 16. 

 •p. niagarensis, Hall, = Acroculia niagarensis, Hall, Pal. N. Y., 



Vol. ii, pa. 288, pi. 60, f. 3 341 



Platyostoma niagarensis. Hall, Pal. N. Y., Vol. ii, pa. 287, pi. 60, f. 1 342 



Porcellia senex, W. and M., Mem. Bost. Soc. Nat. Hist., Vol. i, pa. Ill, pi. 3, f. 6. 

 = Platyceras. 



Bucaijia angustata, Hall 346 



;^B. chicagoensis, M'C, New Pal. Fossils, pa. 69, pi. 8, f. 4 & 5. 1860. 



*B. crassolare, M'C, New Pal. Fossils, pa. 91. 1861. 



*B. pervoluta, M'C, New Pal. Fossils, pa. 91. 1861. 



Bellerophon {Bucania) per for atus, "W. and M., Mem. Bost. Soc. Nat. Hist., Vol. i, 

 pa. 100, pi. 3, f. 7. 



= Tremanotus alpheus, Hall. 



CEPHALOPODA. 



Orthoceras abnorma. Hall 355 



O. alienum, Hall 354 



O" angulatum ? Wahl 353 



O. annulatum, Sowerby 351 



= 0. nodocostum, M'C, loc. cit. 



•O. cameolare, M'C., New Pal. Fossils, p. 93. 1861. 



O. columnare, Hall, Geol. Rep. "Wisconsin, p. 4, 1860 351 



O. crebescens, Hall 354 



•O. hoyi, M'Chesney, New Pal. Fossils, p. 92. 1861. 



O. irregulare, M'C, New Pal. Fossils, pa. 94, pi. 7, f. 7. 1861. 



= 0. woodworthi, Idem, expl. plates. 



•O. laphami, M'C, New Pal. Fossils, p. 91. 1861. 



*0. lineolatum, M'C, New Pal. Fossils, p. 93. 1861. 



O. niagarense, Hall 856 



;:0. medullare, Hall, Geol. Rep. Wisconsin, 1860, p. 4 353 & 381 



= 0. stricBlineatum, M'C 



O. nodocostum, M'C, New Pal. Fossils, pa. 94, pi. 9, f. 5. 1861. 



= 0. annulatum. 



O. scammoni, M'C, New Pal. Fossils, p. 92. 1861. 



= ? O. columnare, Hall, loc. cit. 



O. stricelineatum, M'C,New Pal. Fossils, p. 94. 1861. 



= O. medullare. 



'•O. woodworthi, M'C, New Pal. Fossils, pi, 7, f. 7. 



0. irregulare, M'C, loc. cit. 



Cyrtoceras amplicorne, Hall, = (C hercules, loc. cit.) 358 



C. brevicorne. Hall 356 



€. dardanum. Hall, Geol. Rep. Wis., p. 43. 1861 349 



C. fosteri, Hall. Geol. Rep. Wisconsin, p. 4. 1861 349 



C. giganteum, M'C, loc. cit., = Nautilus. 



