170 RESEARCH IN CHINA. 



Solenopleura sp. undt. 



Fragments of the cephalon of a large, strongly tuberculated species resembling 

 Menocephalus abderus (Walcott) and M. acanthus Walcott [plate 16] occur with Dory- 

 pyge richthofeni fauna in Manchuria. The glabella is not so convex or so strongly 

 tuberculated as in those species. Until better material is available the species is 

 referred to Solenopleura as an undetermined species. 



Formation and Locality. Middle Cambrian: (35 n ) Fu-chou series, limestones 

 near base of series just above the white quartzite [see Blackwelder, 19076, p. 92, for 

 general section giving stratigraphic relations] , collected in a low bluff on the shore 

 of Tschang-hsing-tau Island, east of Niang-niang-kung, L,iau-tung, Manchuria, China. 



Collected by J. P. Iddings and Li San. 



Genus CHUANGIA Walcott. 



Chuangia WALCOTT, 1911, Smithsonian Misc. Coll., vol. 57, No. 4, pp. 83-84. (Described and discussed 

 as a new genus essentially as below.) 



This genus is proposed for a group of Upper Cambrian trilobites in which the 

 cephalon has a truncato-conical or subquadrangular glabella; a narrow, concave 

 frontal limb, and, as far as known, a smooth test. 



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

 few indications of segments. 



The general form of the glabella is much like that of some species of Anomocare 

 [see plate 18], but the frontal limb is quite different. The latter suggests Pagodia 

 lotos Walcott [plate 15, fig. 12], but the frontal limb of the latter is absorbed by the 

 rounded frontal rim. In Chuangia the frontal limb and rim meet to form an angle 

 and the rim does not rise above the upward sloping surface of the frontal limb. 



Genotype. Ptychoparia ? batiaWalcott [19056, Proc.U.S. Nat. Mus.,vol. xxix, 

 p. 75, and Walcott, 1911, plate 15, figs. 3, 30]. Three other species known from the 

 Upper Cambrian formations of China: Chuangia nitida, C. nais, and C. fragmenta. 



Chuangia batia (Walcott). 

 Plate 17, Figures 20, 2oa-d. 



Ptychoparia ? batia WALCOTT, 1905, Proc. U. S. Nat. Mus., vol. xxix, p. 75. (Species described 



essentially as below.) 

 Chuangia batia (WALCOTT), 1911, Smithsonian Misc. Coll., vol. 57, No. 4, p. 84, pi. 15, figs. 3, 30. 



(Referred and figured as genotype of new genus Chuangia.) 



Cephalon, exclusive of the free cheeks, subrhomboidal, moderately convex. 

 Glabella truncato-conical ; a specimen with a length of 1 1 mm. has a width at the 

 base of n mm., and at the broadly rounded, almost transverse front, of 7 mm.; 

 very faint traces are shown of a posterior pair of furrows; occipital furrow nearly 

 straight, shallow, rounded, and narrow; occipital ring strong, very slightly convex, 

 and slightly wider at the center than at the ends; it is marked at the center, near the 

 occipital furrow, by a minute node ; dorsal furrow distinctly but not deeply marked. 



Fixed cheeks wide and slightly convex, nearly flat between the glabella and 

 palpebral lobe, and curved downward in front to the frontal rim and backward to 

 the furrow within the posterior margin; palpebral ridge narrow and low, but dis- 

 tinctly shown; posteriorly it passes into the palpebral lobe; palpebral lobe small, 

 and situated a little back of a transverse line drawn through the center of the 

 cephalon ; postero-lateral limb large, about as long as the base of the glabella is wide, 

 and marked by a strong furrow within the elevated posterior margin. The front 

 of the glabella and of the fixed cheeks curves down into a shallow furrow, from which 

 the frontal rim rises before curving over to form a thick frontal margin, which is 

 marked by longitudinal, raised striae. 



