62 BULLETIN 53, UNITED STATES NATIONAL MUSEUM. 



191. Arcopagella (?) macrodonta INIeek. Holotype. 



Dakota (Cret. ). Bij^ Sioux River, three miles above its 

 mouth, South Dakota. 



Meek, Kept. U. vS. Geol. Surv. Terr., IX, 1876, p. 202, pi. i, fig. 2. 



12411. Arcopagella mactroides Meek. Holotj-pe and paratype. 



Mentor (Cret.). Twelve niile.s southwest of Salina, 

 Kansas. 



Meek, Fourth Ann. Rept. U. vS. Geol. vSurv. Terr., 1871, p. 309, 

 text figs. A, B; Rept. U. vS. Geol. Surv. Terr., IX, 1876", p. 



2u2, pi. 2, figs. 4a, 4b. 



13328. Arcopagia unda Conrad. Holotype. 



Miocene. Shore of vSanta Barbara County, California. 



Conrad, Rept. Expl. and vSurv. R. R. Miss. Riv. to Pacific Ocean, 

 YII, 1857, p. 192, pi. 4, figs. 3, 4. 



[May be the same as Metis alta (Conrad). W. H. Dall.] 



24560. Arethusina americana Walcott. Cotj'pe. 



Upper Cambrian. North of Dunderberg mine. Eureka 

 Di.strict, Nevada. 



Walcott, Mon. VIII, U. vS. Geol. Surv., 1SS4, p. 62, pi. 9, fig. 27. 



42436. Arges wesenbergensis paulianus Clarke. Cotype. 



Trenton (Ord.). vSt. Paul, Minnesota. 



Clarke, Geol. and Nat. Hist. Surv. Minn., Final Rept., Ill, Pt. II, 

 1S94, ]). 745, fig. 64. 



109294. Argyrotheca schucherti Dall. Holotype. 



Miocene. Jackson Bltiff, Ocklockonee River, Florida. 



Dall, Trans. Wagner Free Inst. vSci. Phila., Ill, Pt. VI, 1903, 

 P- 1539. pl- 58, fig. 8. 



35230. Arionellus levis Walcott. Holotype. 



Middle Cambrian. Crowfoot section, Gallatin Range, 

 Yellowstone National Park. 



Walcott, Mon. XXXII, Pt. II, U. S. Geol. Surv., 1899, j). 462, 

 pi. 65, fig. I. 



1 180. Arionellus ( Crepicephalus) oweni Meek and Ha^'den. 



Holotj-pe. 

 Upper Cambrian. Near head of Powder River, Big Horn 

 Motintains, Wyoming. 



Meek and Hayden, Proc. Acad. Nat. Sci. Phila., for 1861, p. 436; 

 Anier. Journ. vSci. (2), XXXIII, 1862, p. 74, fig. 4. 



= Ptychoparia oweni. 

 See Agratdos oweni. 



46092. Aristerella nitidula Ulrich. Cotypes. 



46093. Black River (Ord.). Chatfield and St. Paul, Minnesota. 



Ulrich, Geol. and Nat. Hist. vSurv. JMinn., Final Rept., Ill, Pt. H, 

 1S94, p. 524. pl- 35. fig-'^- 3'->-39- 



