574 BULLETIN 92, UNITED STATES NATIONAL MUSEUM. 



Gyroceras duplicostatum Whitfield. 



Gyroceras duplicostatum Whitfield, Ann. Rep. Geol. Surv. Wisconsin for 1877, 



1878, p. 78; Geol. Wisconsin, 4, 1882, p. 235, pi. 7, fig. 1. Chamberlin, Geol. 



Wisconsin, 1, 1883, p. 159, fig. Clarke, Geol. Minnesota, 3, pt. 2, 1897, p. 811. 

 Black River (Platteville): Beloit, Janesville, etc., Wisconsin. 



Gyroceras elrodi White. 



Gyroceras elrodi White, llth Ann. Rep. Indiana Dep. Geol. Nat. Hist., 1882, p. 



356, pi. 37, fig. 1; pi. 38, figs. 2-4. Lesley, Geol. Surv. Pennsylvania, Rep. 



P 4. 1889, p. 268, figs. 



Barrandeoceras elrodi Miller, N. A. Geol. Pal., 2d App., 1897, p. 771 (gen. ref.). 

 Niagaran (Laurel) : Hartsville, Indiana. 



Gyroceras farcimen Clarke and Ruedemann. 



Gyroceras farcimen Clarke and Ruedemann, Mem. New York State Mus., 5, 1903, 



p. 92, pi. 18, figs. 1-4. 

 Niagaran (Guelph): Shelby, New York. 



GYROCERAS HERCULES Chamberlin. See Protophragmoceras hercules. 

 GYROCERAS (LITUITES) MAGNIFICUM Billings. See Apsidoceras magnificum. 

 GYROCERAS PARADOXICUM Hall. See Orthoceras paradoxicum. 



Gyroceras rhombolineare Owen. Not recognized. 



Gyroceras rhombolinearis Owen, Geol. Surv. Indiana, 1862, p. 362, fig. 4. 

 Silurian: Locality not given. 



GYROCERAS (LITUITES) VAGRANS Billings. See Barrandeoceras vagrans. 



GYRONEMA Ulrich. Genotype: G. pulchelluin Ulrich and Scofield. 



Gyronema (subgenus of Trochonema) Ulrich, Geol. Minnesota, 3, pt. 2, 1897, p. 

 1054. Koken, Neuea Jahrb. f. Min., Geol. Pal., 1, 1898, p. 24. 



Gyronema brevispira Whiteaves. 



Gyronema brevispira Whiteaves, Geol. Surv. Canada, Ann. Rep., n. s., 14, 1904, 



App. F, p. 51; Geol. Surv. Canada, Pal. Foss., 3, pt. 4, 1906, p. 259, pi. 29, 



fig. 4. 

 Niagaran: Ekwan River, Canada. 



Gyronema dowlingi Whiteaves. 



Gyronema Dowlingii Whiteaves, Geol. Surv. Canada, Ann. Rep., n. s., 14, App. 



F, 1904, p. 50; Geol. Surv. Canada, Pal. Foss., 3, pt. 4, 1906, p. 259, pi. 



29, fig. 3. 

 Niagaran: Ekwan River, Canada. 



Gyronema duplicatum Ulrich and Scofield. 



Gyronema duplicatum Ulrich and Scofield, Geol. Minnesota, 3, pt. 2, 1897, p. 



1055, pi. 78, figs. 22-25. 

 Trochonema (Gyronema) duplicatum Grabau and Shimer, N. A. Index Fossils, 1, 



1909, p. 671, fig. 928g, h. 



Black River (Platteville): Beloit, etc., Wisconsin; Dixon, Illinois. 

 Cotype.Czt. No. 45823, U.S.N.M. 



Gyronema historicum (Hudson). 



Eunema historicum Hudson, Bull. New York State Mu?., 80, 1905, p. 288, pi. 4, 



fig. 5. 

 Gyronema historicum Raymond, Ann. Carnegie Mus., 4, 1908, p. 208, pi. 54, 



figs. 5, 6. 



Cyclonema? normaliana Raymond, Amer. Jour. Sci., 4th Ser., 20, 1905, p. 377. 

 Chazyan (Valcour): Valcour Island and Plattsburg, New York. 



