516 BULLETIN 53, UNITED STATES NATIONAL MUSEUM. 



13929. Platyceras conradi Walcott. Cotypes. 



Middle Devonian. Combs Peak, Eureka District, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 1884, p. 182, pi. 16, figs. 1, ia. 



45954. Platyceras ? depressum Ulrich and Scofield. Holotype. 



Black River (Ord.). Near Cannon Falls, Minnesota. 



Ulrich and Scofield, Geol. and Nat. Hist. Surv. Minn., Final 

 Rept., Ill, Pt. II, 1897, p. 1069, pi. 61, figs. 55, 56. 



23846. Platyceras hoyti Walcott. Holotype. 



Upper Cambrian. Four miles west of Saratoga Springs, 

 New York. 

 Walcott, Proc. U. S. Nat. Mus., XIII, 1890, p. 268, pi. 20, fig. 8. 



8504. Platyceras nebrascense Meek. Plesiotypes. 



8505. Upper Carboniferous. Near Santa Fe, New Mexico, and 



Nebraska City, Nebraska. 



White, Rept. U. S. Geogr. Surv. W. 100th Merid., IV, Pt. I, 1876, 

 p. 159, pi. 12, figs. 5a-5d. 



13926. Platyceras nodosum Conrad. Plesiotype. 



Middle Devonian. Lone Mountain, near Eureka, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 1884, p. 183, pi. 6, figs. 5-5D. 



14405. Platyceras occidens Walcott. Cotype. 



Dower Carboniferous. Eureka District, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 1884, p. 254, pi. 24, figs. 

 9. 9 a - 



35362. Platyceras parvum Swallow. Plesiotypes. 



Hermosa (Upper Carb.). Sandstone Mountain, Rico 

 quadrangle, and Bear Creek, Needle Mountain quad- 

 rangle, Colorado. 



Girty, Prof. Pap. No. 16, U. S. Geol. Surv., 1903, p. 461, pi. 10, 

 figs. 1, ia; 2, 2a. 



14406. Platyceras piso Walcott. Holotype. 



Lower Carboniferous. Eureka District, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 1884, p. 254, pi. 24, figs. 

 7-7b. 



1537 1. Platyceras primaevum Billings. Plesiotype. 



Lower Cambrian. Tro}\ New York. 



Walcott, Bull. No. 30, U. S. Geol. Surv., 1886, p. 130, pi. 12, figs. 

 5, 5a; Tenth Ann. Rept. U. S. Geol. Surv., 1890, p. 618, pi. 

 74, figs. 11, 11a. 



35217. Platyceras primordialis Hall? Plesiotype. 



Middle Cambrian . Soda Butte Creek, Yellowstone National 

 Park. 



Walcott, Mon. XXXII, Pt. II, U. S. Geol. Surv., 1899, p. 453, pi. 

 63, fig. I. 



