■'^"^ ^- Sun— Cambrian Faunas of North China (iv) 67 



Width of frontal limb 1.4 mm. 0.8 mm. 



Width of frontal rim 1.4 mm. 0.9 mm. 



In form this species resembles Solenoj)lewa herce Walcott from Yen-Chuang, 

 Shantung ; bat it differs in the presence of the distinct occipital ring and also of the pal- 

 pebral ridge. 



The presence of the palpebral ridge and the distinct occipital node suggest Soleno- 

 pleura holometopa Angelin, but the position of the palpebral lobe and the proportionally 

 shorter glabella serve to distinguish it. In this species the length of the glabella and its 

 width at the base are subequal, while in the Swedish species the glabella is usually longer 

 than wide. 



^loreover, the palpebral ridge of our species extends from the anterior part of the 

 palpebral lobe to the dorsal furrow, just a little in front of the second furrow of the gla- 

 bella, while in S. holometopa it is distinctly marked and extends to the dorsal furrow one 

 sixth the length of the glabella from the frontal margin of the glabella. 



Genus Chuangia Walcott 



1911 Chuangia Walcott, Smithsonian Miss. Coll., Vol. 57, No. 4, pp. 83-84. 

 1913 Chuangia Walcott, Research in China, Vol. 3, pp. 170-172. 



Original description: "This genus is proposed for a group of Upper Cambrian 

 trilobites in which the cephalon has a truncato-conical or sub-quadrangular glabella; a 

 narrow, concave frontal limb and so far as known, a smooth test. 



' 'The associated pygidium is large, with a strong axis, broad pleural lobes, and 

 few indications of segments". (Walcott 1913 pp. 170-172). 



Doctor Walcott compared the genus with Anomocare and Ptychoparia on account 

 of the likeness of the general form of the cranidium. He also states under the description 

 of the genus, that the characteristic frontal limb of Chuangia serves to distinguish it from 

 the other two genera ; and the genus Chuangia is characterized by the concave frontal 

 limb which meets with the rim to form an angle and the rim does not rise above the 

 dupwar sloping surface of the frontal limb. 



In the Tai-An material collected by the college excursion, the outer shell of this 

 genus was discovered and the shell or test is strongly marked by fine pustules ; when the 

 outer shell is extoliated, the cranidium appears smooth. 



Genotype — Chuangia batia Walcott. 



