42 PROCEEDINOS OF THE NATIONAL MUSEUM. vol. xxix. 



horizon in China appears to resemble more closely than any other 

 form the pygidium of this species. As illustrated and described by 

 M. Bergeron it differs from Damesella cMone in its shorter axis, live 

 instead of six spines on the margin, and a smooth instead of granulose 

 surface. Damssella chione has a head of essentially the same type as 

 that of D. hlack^ii elder ij but the pygidium differs in having its anch}^- 

 losed segments extending out directly across the border into the falcate 

 spinose ends, instead of stopping within the border and having spines 

 representing the extension of the segments extending outward from 

 the border. 



Specimens of Drejjanura Bergeron and Agnostus douviUei Bergeron 

 are associated with Damesella chione^ and Ptyclioparia ceus Walcott 

 and SJiangtungia spinifera Walcott occur at the same horizon and in 

 many instances on the same hand specimen with D. chione. 



Formation and locality.- — Middle Cambrian, Ku San shale forma- 

 tion; 2.5 miles southwest of Yen Chuang, Hsin Tai, and in isolated 

 hills 12 miles S. 80° E. of Tai An Fu, Shangtung, China. 



Collected by Eliot Blackwelder, of the Carnegie Institution of 

 Washington Expedition to China. 



Genus AGRAULOS Corda. 

 AGRAULOS ABARIS, new species. 



Glabella and lixed cheeks convex, subrhomboidal in outline and 

 strongly rounded in front. Glabella moderately convex; sides slightly 

 converging; front broadly rounded; surface marked bj^ three short 

 and ver\" slightly impressed furrows; occipital furrow shallow and 

 arching slightly forward at the center. Occipital ring narrow at the 

 sides, gradually increasing in width to the broad base and a strong 

 occipital spine. 



Fixed cheeks slightly convex, about half the width of the glabella; 

 between the glabella and palpebral lobes the cheeks are almost flat; 

 posteriori}' they slope rapidl}^ downward to the short postero-lateral 

 limbs; in front they also slope rapidly downward and merge into the 

 frontal limb; palpebral lobes small; ocular ridges narrow and faintly 

 defined; frontal limb slights prominent at the central portions, where 

 it merges into the rounded frontal rim, the line of demarcation 

 between the two being very slightly defined; at the sides the frontal 

 rim narrows and is elevated above the lateral extension of the frontal 

 limb; dorsal furrows very distinctly defined. 



Surface apparenth' smooth under a strong lens, with the exception 

 of very indistinct irregular lines that radiate from the front of the 

 glabella outward across the frontal limb. 



The one specimen of this species in the collection has a length of 

 5 mm. exclusive of the occipital spine. The width at the palpebral 



