NO. 4 CAMBRIAN TRILOHITES, 2D CONTRIBUTION RESSER 29 



Genotype. — Ptychoparia- {Soleno pleura?) hreviceps Walcott. 



Range. — Upper Cambrian. 



Name. — oAiyos = little ; fi€Toirov= forehead. 



Oligometopus breviceps (Walcott) 



Ptychoparia {Solenopleura?) brcznceps Walcott, U. S. Geol. Surv. Mon. 8, 



p. 49, pi. 10, fig. 9, 1884. 

 Pagodia breviceps Walcott, Smithsonian Misc. Coll., vol. 57, no. 13, pi. 361, 



no. 13, 1914. 



Upper Cambrian, Secret Canyon (loc. 62) ; near Adams Hill. 

 Eureka district, Nevada. 

 Holotype. — U.S.N.M. no. 24577. 



