NO. 5 CAMBRIAN TRILOBITES RESSER 4I 



furrow and rim well developed. Brim about one-third as wide as 

 glabella is long ; heavy, thickened, up-turned rim separated by strong 

 anterior furrow ; preglabellar area almost obsolete in front of glabella. 

 Fixed cheeks narrow, consisting entirely of the strongly arched palpe- 

 bral lobes and apparently narrow straps. Eyes rather large. 



Genotype .—Ptychoparia ? metra Walcott. 



Range. — Middle Upper Cambrian. 



Name. — M£reopos = high ; ao-7rt«? = shield. 



Meteoraspis metra (Walcott) 

 Ptychoparia f metra Walcott, Proc. U. S. Nat. Mus., vol. 13, p. 273, pi. 21, 

 fig. 7, 1890. 



Upper Cambrian, Wilberns ; (loc. 67) Potatotop, 7 miles northwest 

 of Burnet and (loc. 68) Packsaddle Mountain, 11 miles southeast of 

 Llano, Texas. 



Holotype.— U.S. N.M. no. 23858. 



MODOCIA Walcott, 1924 



Modocia Walcott, Smithsonian Misc. Coll., vol. 75, no. 2, p. 59, 1924 ; idem, no. 3, 

 p. 106, 1925. 



Genotype. — Arionelliis (CrepicepJiolus) ozveni Meek and Hayden. 

 Range. — Upper Cambrian. 



DESCRIBED SPECIES REFERRED TO MODOCIA 



Modocia oweni (Meek and Hayden) 

 Arionelliis (Crepicephalns) ozveni Meek and Hayden, Proc. Acad. Nat. Sci. 



Philadelphia, 1861, p. 436. 

 Modocia oweni Walcott (part), Smithsonian Misc. Coll., vol. 75, no. 2, p. 59, 



pi. 12, figs. I, 2, 1924; idem, no. 3, p. 106, pi. 16, figs, i, 2, (not 



3 = M. centralis), 1925. (Not Ptychoparia ozveni Walcott::^ Ehmania 



oweni. ) 



This trilobite was referred by various authors to Agraulos, Ptycho- 

 paria, and Crepicephalus. Also several other species were included 

 under this name. Study of the types shows that the species occurs 

 only at the locality given below. 



Upper Cambrian, Deadwood ; head of Powder River, Big Horn 

 Mountains, Wyoming. 



Holotypc.— U.S. 'N.M. no. 1180. 



Modocia centralis (Whitfield) 



Crepicephalus (Loganellus) centralis Whitfield, Prelim. Rep. Pal. Black 

 Hills, U. S. Geol. Surv., p. 10, 1877 ; Rep. Geol. Res. Black Hills, U. S. 

 Geogr. and Geol. Surv., p. 341, pi. 2, figs. 21-24, 1880. 



Modocia oweni Walcott (part), Smithsonian Misc. Coll., vol. 75, no. 2, p. 59, 

 pi. 12, fig. 7, 1924 ; idem, no. 3, p. 106, pi. 16, fig. 3, 1925. 



