558 BULLETIN 53, UNITED STATES NATIONAL MUSEUM. 



15443. Ptychoparia housensis Walcott. Holotype. 



Middle Cambrian. House Range, Antelope Springs, Utah. 



Walcott, Bull. No. 30, U. S. Geol. Surv., 1886, p. 201, pi. 25, fig. 5. 



24614. Ptychoparia laeviceps Walcott. Cotype. 



Middle Cambrian. Secret Canyon, Eureka District, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 1884, p. 54, pi. 10, figs. 



17, 18. 



2461 1. Ptychoparia (?) linnarssoni Walcott. Cotype. 



Middle Cambrian. Secret Canyon, Eureka District, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 18S4, p. 47, pi. 9, figs. 



18, 18a. 



23857. Ptychoparia llanoensis Walcott. Cotypes. 



Upper Cambrian. Packsaddle Mountain, Llano County, 

 Texas. 



Walcott, Proc. U. S. Nat. Mus., XIII, 1890, p. 272, pi. 21, figs. 3, 

 4, 5; Mon. XXXII, U. S. Geol. Surv., Pt. II, 1899, p. 458, 

 pi. 64, fig. 4. 



24613. Ptychoparia (Pterocephalus) occidens Walcott. Holotype. 

 Upper Cambrian. East of Hamburg Ridge, Eureka Dis-' 

 trict, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 1884, p. 58, pi. 9, fig. 21. 



24612. Ptychoparia occidentalis Walcott. Cotype. 



Middle Cambrian. Secret Canyon, Eureka District, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 1884, p. 51, pi. io, fig. 5. 



24610. Ptychoparia oweni Meek and Hayden. Plesiotype. 



Middle Cambrian. Eureka District, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 1884, p. 55, pi. 10, figs. 

 3, 3a. 



See Agraulos oweni, Arionellus (Crepicephalus) oweni, 

 and Conocoryphe (Ptychoparia) gallatinensis. 



35231. Ptychoparia penfieldi Walcott. Cotypes. 



Flathead (Middle Cambrian). Crowfoot section, Gallatin 

 Range, Yellowstone National Park. 



Walcott, Mon. XXXII, Pt. II, U. S. Geol. Surv., 1899, p. 456, 

 pi. 65, figs. 4, 4a, 4b. 



24608. Ptychoparia (?) pernasutus Walcott. Cotypes. 



Upper Cambrian. East of Hamburg Ridge, Eureka Dis- 

 trict, Nevada. 



Walcott, Mon. VIII, U. S. Geol. Surv., 1884, p. 49, pi. 10, figs. 

 S-Sb. 



= Anomocare pernasutus. 



23859. Ptychoparia pero Walcott. Cotypes. 



Upper Cambrian. Morgans Creek, Burnet County, Texas. 

 Walcott, Proc. U. S. Nat. Mus., XIII, 1890, p. 274, pi. 21, fig. 6. 



