76 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxix. 



This species is characterized by its large size, concave frontal rim, 

 and nearly smooth glabella. In view of the occurrence of heads of 

 the genus Dorijpy<jella at about the same horizon, which reseml)le 

 this, the generic reference is somewhat doubtful. A somewhat simi- 

 lar head occurs in the upper poi'tion of the Chao Mi Tien limestone 

 at about the same horizon, 9 miles north of Hsin Tai Hsien. 



FoTindtion and locality. — Upper Cambrian, Chao Mi Tien foi-ma- 

 tion; 2.7 and 3 miles southwest of Yen Chuang, Hsin Tai, Shangtung, 

 China. A form apparently identical was found by Mr. Blackwelder 

 in limestone blocks in talus at Chao Mi Tien. 



Collected 1)v Kliot P>lackwelder, of the Carnegie Institution of 

 Washington Expedition to China. 



PTYCOPARIA (?) BROMUS, new species. 



This species is represented by the central portions of the head, 

 exclusive of the free cheeks. Glabella moderately convex, truncato- 

 conical, rounded in front, and apparently without furrows; occipital 

 furrow transverse and clearl}" defined; occipital ring strong and mod- 

 eratel}^ convex; dorsal furrow broad and shallow. 



Fixed cheeks nearly as wide as the glal)e,jja opposite the palpebral 

 lobe; they rise slightl}^ from the dorsal furrow to the palpebral lobe, 

 and slope gently backward to the postero-lateral limb and forward to 

 the frontal limb; palpel)ral lo)>e narrow, about one-third the length of 

 the head; ocular ridge rounded and faintly defined; frontal limb of 

 medium width, slightly convex, and sloping gently down to a rounded 

 furrow that separates it from the flattened frontal rim, which is about 

 one-half as wide as the frontal limb. 



The surface is slightl}^ roughened by minute granulations, as seen 

 with the aid of a strong lens. The largest specimen of the head in 

 the collection has a length of 7 nmi. 



This species is characterized by the rounded, smooth appearance of 

 the glabella, fixed cheeks, dorsal furrow, and frontal liml). 



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

 tion; 2.5 miles southwest of Yen Chuang, Hsin Tai, Shangtung, 

 China. 



Collected hy Eliot Blackwelder, of the Carnegie Institution of 

 Washington Expedition to China. 



PTYCHOPARIA CEUS, new species. 



Outline of head, exclusive of free cheeks, transversely subrhomboidal, 

 broadly rounded in front, convex; glal)ella conical, moderately con- 

 vex, and marked by two pairs of short, shallow furrows that extend 

 in but a short distance on the sides; occipital furrow rounded, very 

 distinct, and continued outward on the postero-lateral limbs, where it 

 is stronger and deeper; occipital ring narrow at the sides, gradually 



