22 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 95 



Orygmaspis Uanoensis (Walcott) 



Ptychoparia Uanoensis Walcott, Proc. U. S. Nat. Mus., vol. 13, p. 272, pi. 



21, figs. 3-5, 1890; U. S. Geol. Surv. Mon. 32, pt. 2, p. 458, pi. 64, fig. 4, 



1899- 

 Conaspis Uanoensis Walcott, Smithsonian Misc. Coll., vol. 57, no. 13, p. 358, 



1914. 



Upper Cambrian, Wilberns; (loc. 68) Packsaddle Mountain, ii 

 miles southeast of Llano, Texas. 

 Cotypes.—\].SMM. no. 23857. 



Orygmaspis eryon (Hall) 



ConocephaUtes eryon Hall, i6th Ann. Rep. New York State Cab. Nat. Hist., 



p. 157, pl- 7, figs. 10-16, 1863. 

 Conaspis eryon Hall, idem, p. 152, 1863. 

 Conaspis eryon Walcott, Smithsonian Misc. Coll., vol. 57, no. 13. p. 358. 



1914. 



Upper Cambrian, Franconia ; Trempealeau, and other localities in 

 Wisconsin. 



Cotypes. — A.M.N.H. no. 327; casts, U.S.N.M. no. 89936; meta- 

 types, U.S.N.M. no. icon. 



PERIOMMA Resser, 1936 



Periomma leuka (Walcott) 



Olenopsis leuka Walcott, Smithsonian Misc. Coll., vol. 67, no. 3, p. 77, pl. 13, 

 fig. 4, 1 91 7. 



This species is not quite typical of the genus, but the extra width 

 of the brim may be attributable to the coarse matrix. 



Lower Cambrian, Mount Whyte; (loc. 58g) Mount Bosworth, 

 British Columbia. 



Holotype. — U.S.N.M. no. 64397. 



Periomma cilles (Walcott) 



Ptychoparia ? ciUcs Walcott, Smithsonian Misc. Coll., vol. 67, tio. 2, p. 32, 

 pl. 6, fig. 2, 1917. 



Lower Cambrian, Mount Whyte; (loc. 63d) Ptarmigan Peak, 

 northeast of Lake Louise, Alberta. 

 Holotype.— U.S.^M. no. 63737. 



PLAGIURELLA, n. gen. 



Small trilobites which have the same general aspect as Plagiura in 

 that the facial suture has such a strong converging direction forward, 

 seem to require separate generic recognition. 



