72 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxix. 



Formation and locality. — Upper Cambrian, lower portion of Chao 

 Mi Tien forma'ion, in a gray, somewhat coarse, fossiliferous lime- 

 stone; 2.7 miles southwest of Chao Mi Tien, Shang-tung, China. 



Collected ])y Eliot Blackwelder, of the Carnegie Institution of 

 Washington Expedition to China. 



PTYCHASPIS CALLISTO, new species. 



Of this species only the central portions of the head, exclusive of 

 the free cheeks, are known. Glabella moderately convex, and divided 

 into a narrow posterior lobe by a broad, rounded, deep, transverse 

 furrow that curves slightly backward, and an anterior lobe, about as 

 long as wide, marked upon its lateral slopes by two pairs of short, 

 narrow furrows; it is broadly rounded, almost transverse in front, 

 and its sides are sub-parallel; occipital furrow broad and deep and arch- 

 ing slightly forward at the center; occipital I'ing narrow at the ends, 

 widening and rising gradually toward the center, which appears to 

 have been elevated above the general surface of the head; dorsal fur- 

 rows strong and deep. 



Fixed cheeks narrow, rising abruptly from the dorsal furrow and 

 extending laterally to the furrow within the rim of the palpebral lobe; 

 they slope gentl}^ backward to the postero-lateral limb, and more 

 abruptly forward to a strong furrow that separates the frontal rounded 

 margin of the head from the glal)ella; frontal limb and rim combined 

 in a rounded frontal border, which corresponds in its section to about 

 the same curvature as the section of the furrow between the border 

 and the glabella; postero-lateral lini])s about as long as the width of 

 the glabella, and marked by a broad, rather deep groove within the 

 narrow posterior margin. 



Surface of the cast of the interior of the test with numerous rather 

 large scattered punctae and very tine punctte seen only with the aid of 

 a strong lens; a fragment of the outer surface shows it to have been 

 strongl}' pimctate, with tine puncta3 corresponding to the puncta? seen 

 on the cast of the interior. The largest head in the collection has a 

 length of 18 mm. 



This species is strongly characterized by the l)road, strong posterior 

 furrow and narrow posterior lobe of the glabella, and the sub-quadrate, 

 moderately convex frontal lobe; also the elevated occipital ring and 

 punctate surface. 



Formatioii and locality. — Upper portion of the Chao Mi Tien 

 formation, at the same horizon as P. caciis and P. ceto; 2.7 miles 

 southwest of Yen Chuang, Hsin Tai, Shangtnng, China. 



Collected by Eliot Blackwelder, of the Carnegie Institution of 

 Washington Expedition to China. 



PTYCHASPIS CALYCE, new species. 



In general form, convexity, and size the corresponding parts of this 

 species follow that of P. ceto. It ditfers from the latter in having a 



