20 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 97 



Clappaspis appears to be related to Ehmaniella or at least most 

 closely resembles that genus. The only ditTerences of consequence are 

 the slightly narrower preglal)ellar area and the granulated surface, for 

 the pygidia are clearly constructed on the same plan. 



CLAPPASPIS SPENCEI, n. sp. 



Plate 6, figs. 5, 6 



This is the widest of the five species recognized in the Spence shale. 

 It is further distinguished by two sets of granules rather evenly dis- 

 tributed, the smaller ones being more numerous. Exfoliated speci- 

 mens have coarse irregular striations on the preglabellar area. 



Locality 55c. 



Holotypc and parafypes.- — U.S.N.M. no. 96530. 



CLAPPASPIS IDAHOENSIS, n. sp. 



Plate 6, figs. 26, 27 



Three complete individuals represent this species. The cranidium 

 is narrower than C. spencei and has a shorter, more conical glabella. 

 C. idahoensis is characterized by scattered granules of uneven size. 

 The thorax has 14 segments. 



Locality 55c. 



Holotype and paratypcs. — U.S.N.M. no. 96531. 



CLAPPASPIS LANATA, n. sp. 



Plate 6, fig. 7 



A single cranidium represents this species, which has a narrow 

 cranidium, long glabella, and the surface is closely crowded with small 

 granules. Rather heavy striations occur on the preglabellar area. 



Locality 55c. 



Holotype.— V .S.N M. no. 96532. 



CLAPPASPIS CORIACEA, n. sp. 



Plate 6, figs. II, 12 



This species is rather wide. Coarse granules are widely scattered 

 over the surface, which is covered with a small set of closely crowded 

 granulations. Exfoliated specimens appear pitted. 



Locality 55c. 



Holotype and paratypes. — U.S.N.]\L no. 96533. 



