20 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 93 



Upper Cambrian, Weeks ; (loc. 30o) Weeks Canyon, House Range, 

 Utah. 



Lcctotype and Pamtypcs. — U.S.N.M. nos. 62778-80. 



CLAVASPIDELLA Poulsen, 1927 



Clavaspidclla Poulsen, Meddels. Gr0nland, vol. 70, p. 277, 1927. 



Athabascia Raymond, Amer. Journ. Sci., 5th ser., vol. 15, no 88, p. 311, 1928. 



This genus differs from the others of the group formerly referred 

 to Bathyitriscus in having a more rapidly expanding glabella anterior 

 to the eyes, and in its large tail in which the pleural furrows extend 

 to the margin, increasing in width toward their extremities. 



Genotype. — C. sinupyga Poulsen. 



Range. — ^Middle Cambrian. 



Poulsen was uncertain as to the age of the Cape Frederick VII 

 formation, but it seems clearly to represent a portion of the Stephen 

 formation and is therefore Middle Cambrian. 



DESCRIBED SPECIES REFERRED TO CLAVASPIDELLA 



Poulsen described three species : 



Clin'aspidclla sinupyga Clavaspidclla platyrrhina 



Clavaspidclla quinqucsnlcata 



Raymond also referred to Athabascia : 



Athabascia osthciincri Raymond Athabascia bclus (Walcott) 



Athabascia glacialis Raymond 



Clavaspidella howelli (Walcott) 



Bathyuriscus hozvelli Walcott, U. S. Geol. Surv. Bull. 30, p. 216, pi. 30, figs. 2, 

 2a, 1886. Walcott, Smithsonian Misc. Coll., vol. 64, no. 5, p. 343, pi. 

 47, figs, i-iii, 1916. 



Middle Cambrian, Chisholm: (loc. 31) 3 miles northwest of Pioche, 

 Nevada. 

 Lectotype and paratypes.- — U.S.N.M. no. 15457. 



Clavaspidella bithus (Walcott) 



Bathyitriscus ? bithus Walcott, Smithsonian Misc. Coll., vol. 64, no. 5, p. 340, 

 pi. 47, figs. 4, 4a, 1916. 



Unfortunately, only pygidia of this species have yet been located. 

 When a study of the large quantity of material from this locality is 

 undertaken, heads will likely be found. 



Middle Cambrian, Spence ; (loc. 55c) Liberty Canyon, West of 

 Montpelier, Idaho. 



Lcctotype. — U.S.N.M. no. 62635 ; paratype, no. 62636. 



