(iy) 64 Palseontologia Sinica '^^^- 



the posterior pair shallow and slightly impressed extending from the dorsal furrow to the 

 median ridge where they unite. 



Occipital farrow shallow and broad, merging into the dorsal furrows on both 



sides. 



Fixed cheek very narrow, about one fourth the width of the glabella. Frontal 

 border convex and marked by the broad groove which separates the frontal border from 

 tlu^ glabella. 



Surface finely punctate. 



I place this species under nuadraticephalus because of the quadratiform outhne 

 of the glabella, the presence of a distinct longitudinal median ridge, the narrow fixed 

 cheek and the fine punctate character of the surface, although the frontal border is quite 

 different. Tliis species differs from <l iralcotti in the narrow frontal border, short and 

 broad convex glabella and the glabellar furrows. When a perfect specimen is discovered, 

 other differences may be found. 



Measurement^^: — ' 



Length of cranidium 14.5 ram. 



Length of glabeUa 10.0 mm. 



Width of fixed cheeks opposite the palpebral lobe 2.0 mm. 



Width of frontal border 2.6 mm. 



Horizon and Locality: — Upper Cambrian: from conglomerate limestone of 

 of Kao-Li-Shan (Coll. Y. C. Sun). 



Genus PtyCHASPIS Hall 

 Ptychaspis chinhsiensis Sun (sp. nov.) 



I'late IV, Figs. 8 a-f. 



I!i23 Ptychaspis chinhsihsiensis Sun, Upper Cambrian Fossils from Fengtien. Bulletin of the Geological 

 Society of China Vol. II, No. l-'2 p. 101 (listed). 



This species is represented by several cranidia, separated fixed cheeks, and asso- 

 ciated hypostoma and pygidia. 



Dorsal shield elliptical in outline, moderately convex, with a large genal spine 

 on each side. 



Glabella moderately convex, the greatest convexity in the anterior lobe; it is 

 divided by a broad distinct backwards arching transverse furrow into one long anterior 

 lobe and one narrow transverse lobe. Anterior lobe very long, marked by two pairs of 



