NO. 12 SPENCE SHAI-E AND ITS FAUNA RESSER I3 



GLOSSOPLEURA GIGANTEA, n. sp. 



Plate S, fig- 17 



This is the largest species known in the genus, and is moreover 

 one of the largest Middle Cambrian trilobites known except, of 

 course, the enormous species of Paradoxides. The holotype is over 

 5 inches long, and other fragments show that the average size is 

 nearly as great. 



This species is characterized by a large glabella, somewhat swollen 

 in front. There appear to be 8 thoracic segments. Compared with 

 other Middle Cambrian species, the pygidium of G. gigantea has a 

 distinctly circular outline. 



Locality 20x. 



Holotype. — U.S.N.M. no. 96527. 



CLAVASPIDELLA Poulsen, 1927 

 CLAVASPIDELLA BITHUS (Walcott) 



Plate 5, fig. 12 



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



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

 Clavaspidella bithus Resser, Smithsonian Misc. Coll., vol. 93, no. 5, p. 20, 1935. 



Locality 55c. 



Lectotype. — U.S.N.M. no. 62635 J paratype, no. 62636. 



CLAVASPIDELLA ANAX (Walcott) 



Plate 5, figs. 5, 5 



Bathynriscus ana.v Walcott (part), Smithsonian Misc. Coll., vol. 64, no. 5, 



P- 335- Pl- 48, figs. 1, la, c, d, 1916. 

 Clavaspidella ana.v Resser, Smithsonian Misc. Coll., vol. 93, no. 5, p. 21, 1935. 



Localities 55e and 32X. 



Lectotype. — U.S.N.M. no. 62637; paratypes, nos. 62638-40. 



ORYCTOCEPHALIDAE Raymond 



ORYCTOCEPHALUS Walcott, 1886 



ORYCTOCEPHALUS WALCOTTI Resser 



Plate 2, figs. 15-18 



Oryctoccphalus u'olcotti Resser (part), Smithsonian Misc. Coll., vol. 97, no. 3, 

 p. 9, pl. I, fig. 23, 1938. 



