

NO. 1458. CAMBRIAN FAUNAS OF CHINA— WALCOTT. 585 



Fixed cheeks narrow, uiniost lo.st in the palpebral lobes; in front of 

 the latter they extend forward and downward as narrow, convex 

 ridg-es, merging- into the frontal limb; palpebral lobes strong, about 

 one-third the length of the head; ocular' ridge merged into the fixed 

 cheek on the back side and defined by a short, steep slope on the front 

 side; frontal limb of medium width, slopin-^i; with very little convexit}^ 

 to the narrow furrow separating the frontal limb from the relativel}^ 

 broad, flattened frontal rim; the length of the latter in front of the 

 glabella is a little more than that of the frontal limb. 



Surface slightly roughened by elevated, irregular, more or less 

 inosculating lines upon which numerous minute nodes occur. The 

 result is that on some portions the surface appears to be finely granu- 

 lose, and on others finely punctate, the interspaces between the inoscu- 

 lating lines giving the punctate appearance and the nodes on the lines 

 the granulose appearance. A head 4.5 mm. in length has the same 

 width at the palpebral lobes, exclusive of the free checks. 



Ohstr'vatlons. — The nearest I'elated species is Anomoearella f hura 

 Walcott." It diflFers fr.om the latter in having a short frontal limb 

 between the glabella and frontal rim, relatively larger palpebral lobes, 

 and a stronger dorsal furrow about the glabella. 



Formation and locality. — Upper Cambrian, limestone interbedded 

 in green shales; 4 miles southeast of Yau-t'o, near Wu-t'ai-hien, 8han-si, 

 China. 



Collected by Eliot Blackwelder. 



Genus PTYCHASPIS Hall. 

 PTYCHASPIS BELLA, new species. 



This species is represented b}" a single specimen of the central por- 

 tions of the head, exclusive of the postero-lateral limbs and free 

 cheeks. Glabella subrectangular in outline, moderateh' convex, and 

 crossed by a backward arching furrow which separates a narrow seg- 

 ment from the large anterior lobe, which has a length of 6.5 mm. and 

 a width at the center of 5 mm.; the anterior lobe of the glabella is 

 marked close to the dorsal furrow by very short furrows which indi- 

 cate the second pair of glabellar furrows; the posterior transverse 

 furrow is rather broad and deep at the sides, becoming somewhat 

 shallower at the center; the posterior segment has a uniform width 

 across the central portions, widening out at the ends in front; occip- 

 ital furrow transversely rounded and rather deep; occipital ring 

 transverse, slightly convex, and about the same width as the posterior 

 segment of the glabella; dorsal furrow deep and strong at the sides 

 and in front of the glabella. 



«Proc. U. S. Nat. Mus., XXIX, 1905, p. 56. 



