^o^- J' Sun -Cambrian Faunas of North China (iv) 43 



Measurements : — 



Length of cranidium 8.5 



Width of craniduim opposite the palpebral lobe 10.0 



Length of glabella 5.0 



Anterior width of glabella 2.7 



Posterior width of glabella 5.0 



Width of fixed cheek at the palpebral lobe 2.8 



Width of occipital ring 2.0 



Width of frontal limb and frontal rim combined 2.4 



Horizon and Locality: — Lower Cambrian: from light micaceous purple shale of 

 Cheng-Shan, 8 li from Chao-Kou-Chuang, Luan-Hsien, Chihli (Coll. Y. C. Sun). 



Ptychoparia (Eminerichella) chengshanensis Sun (sp. nov. ) 



Plate III, Figs. 1 a, b. 



This species is represented by several cranidia and associated pygidia probably of 

 this species. 



Cranidium usually broader than long, and apparently smooth. 



Glabellar moderately convex, short and broad, slightly narraw toward the front; 

 the anterior part regularly rounded. Occipital furrows shallow but distinct, merging 

 into the postero-lateral furrow at both sides. 



Occipital ring transverse and comparatively narrow, only slightly broader in the 

 centi'al portion. 



Fixed cheek broad, about the same width as the glabella opposite the palpebral 

 lobe ; slightly convex near the palpebral lobe and becoming flat toward both the front 

 and the postero-lateral furrow. Palpebral ridge very slightly indicated. The facial 

 sutures first cut the frontal border directly backward to the anterior part of the palpebral 

 lobe ; curve around this and then cut the free cheek from the postero-lateral limb with a 

 convex arc. Palpebral lobe of medium size. 



Frontal limb flat and somewhat broader than the frontal rim from which it is 

 separated by a shallow marginal furrow. Frontal rim slightly elevated, broader at the 

 center, becoming narrower toward each side; the frontal margin gently rounded. 



The associated pygidium is rather transverse ; axial lobe very broad, cylindrical, 

 divided by three indistinct furrows into four transverse rings and one terminal portion; 

 pleural lobe also divided by four distinct furrows into five segments. 



